This work was supported by grants to Burcu A. Urgen from The Scientific and Technological Research Council of T&#252;rkiye (Project number: 120K913) and Bilkent University. We thank our pilot participant Sena Er Elmas for bringing the idea of adding background noise between the actor changes, S&#252;leyman Ak&#305; for setting up the light circuit, and Tuvana Karaduman for the idea of using a security camera backstage and her contribution as one of the actors in the study.

A Setup for Human Vision, Cognition, and Interaction in Real-Life Scenarios

<ol>
	<li>Grossman, E. D., Blake, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Brain+areas+active+during+visual+perception+of+biological+motion.">Brain areas active during visual perception of biological motion.</a> Neuron. 35 (6), 1167-1175 (2002).</li><li>Saygin, A. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Superior+temporal+and+premotor+brain+areas+necessary+for+biological+motion+perception.">Superior temporal and premotor brain areas necessary for biological motion perception.</a> Brain. 130 (9), 2452-2461 (2007).</li><li>Peelen, M. V., Downing, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+neural+basis+of+visual+body+perception.">The neural basis of visual body perception.</a> Nature Reviews Neuroscience. 8 (8), 636-648 (2007).</li><li>Caspers, S., Zilles, K., Laird, A. R., Eickhoff, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ALE+meta-analysis+of+action+observation+and+imitation+in+the+human+brain.">ALE meta-analysis of action observation and imitation in the human brain.</a> Neuroimage. 50 (3), 1148-1167 (2010).</li><li>Nelissen, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Action+observation+circuits+in+the+macaque+monkey+cortex.">Action observation circuits in the macaque monkey cortex.</a> Journal of Neuroscience. 31 (10), 3743-3756 (2011).</li><li>Oosterhof, N. N., Tipper, S. P., Downing, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crossmodal+and+action-specific:+Neuroimaging+the+human+mirror+neuron+system.">Crossmodal and action-specific: Neuroimaging the human mirror neuron system.</a> Trends in Cognitive Sciences. 17 (7), 311-318 (2013).</li><li>Lingnau, A., Downing, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+lateral+occipitotemporal+cortex+in+action.">The lateral occipitotemporal cortex in action.</a> Trends in Cognitive Sciences. 19 (5), 268-277 (2015).</li><li>Giese, M. A., Rizzolatti, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+and+computational+mechanisms+of+action+processing:+Interaction+between+visual+and+motor+representations.">Neural and computational mechanisms of action processing: Interaction between visual and motor representations.</a> Neuron. 88 (1), 167-180 (2015).</li><li>Tucciarelli, R., Wurm, M., Baccolo, E., Lingnau, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+representational+space+of+observed+actions.">The representational space of observed actions.</a> eLife. 8, e47686 (2019).</li><li>Tarhan, L., Konkle, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sociality+and+interaction+envelope+organize+visual+action+representations.">Sociality and interaction envelope organize visual action representations.</a> Nature Communications. 11 (1), 3002 (2020).</li><li>Urgen, B. A., Saygin, A. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Predictive+processing+account+of+action+perception:+Evidence+from+effective+connectivity+in+the+action+observation+network.">Predictive processing account of action perception: Evidence from effective connectivity in the action observation network.</a> Cortex. 128, 132-142 (2020).</li><li>Newen, A., De Bruin, L., Gallagher, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Oxford Handbook of 4E Cognition. , (2018).</li><li>Snow, J. C., Culham, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+treachery+of+images:+How+realism+influences+brain+and+behavior.">The treachery of images: How realism influences brain and behavior.</a> Trends in Cognitive Sciences. 25 (6), 506-519 (2021).</li><li>Matusz, P. J., Dikker, S., Huth, A. G., Perrodin, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Are+we+ready+for+real-world+neuroscience.">Are we ready for real-world neuroscience.</a> Journal of Cognitive Neuroscience. 31 (3), 327-338 (2019).</li><li>Zaki, J., Ochsner, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+need+for+a+cognitive+neuroscience+of+naturalistic+social+cognition.">The need for a cognitive neuroscience of naturalistic social cognition.</a> Annals of the New York Academy of Sciences. 1167 (1), 16-30 (2009).</li><li>Hasson, U., Honey, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Future+trends+in+Neuroimaging:+Neural+processes+as+expressed+within+real-life+contexts.">Future trends in Neuroimaging: Neural processes as expressed within real-life contexts.</a> NeuroImage. 62 (2), 1272-1278 (2012).</li><li>Risko, E. F., Laidlaw, K. E., Freeth, M., Foulsham, T., Kingstone, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Social+attention+with+real+versus+reel+stimuli:+toward+an+empirical+approach+to+concerns+about+ecological+validity.">Social attention with real versus reel stimuli: toward an empirical approach to concerns about ecological validity.</a> Frontiers in Human Neuroscience. 6, 143 (2012).</li><li>Parsons, T. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Virtual+reality+for+enhanced+ecological+validity+and+experimental+control+in+the+clinical,+affective+and+social+neurosciences.">Virtual reality for enhanced ecological validity and experimental control in the clinical, affective and social neurosciences.</a> Frontiers in Human Neuroscience. 9, 660 (2015).</li><li>Deuse, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+correlates+of+naturalistic+social+cognition:+brain-behavior+relationships+in+healthy+adults.">Neural correlates of naturalistic social cognition: brain-behavior relationships in healthy adults.</a> Social Cognitive and Affective Neuroscience. 11 (11), 1741-1751 (2016).</li><li>Camerer, C., Mobbs, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differences+in+behavior+and+brain+activity+during+hypothetical+and+real+choices.">Differences in behavior and brain activity during hypothetical and real choices.</a> Trends in Cognitive Sciences. 21 (1), 46-56 (2017).</li><li>Nastase, S. A., Goldstein, A., Hasson, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Keep+it+real:+Rethinking+the+primacy+of+experimental+control+in+cognitive+neuroscience.">Keep it real: Rethinking the primacy of experimental control in cognitive neuroscience.</a> NeuroImage. 222, 117254 (2020).</li><li>Kihlstrom, J. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ecological+validity+and+&amp;#34;ecological+validity&amp;#34.">Ecological validity and &amp;#34;ecological validity&amp;#34.</a> Perspectives on Psychological Science. 16 (2), 466-471 (2021).</li><li>Brunswik, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Perception and the Representative Design of Psychological Experiments. , (1956).</li><li>Aronson, E., Carlsmith, J. M., Gilbert, D. T., Fiske, S. T., Lindzay, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimentation+in+social+psychology.">Experimentation in social psychology.</a> The Handbook of Social Psychology. , 1-79 (1968).</li><li>Ecological validity: Then and now. University of Colorado Available from: <a target="_blank" href="https://www.albany.edu/cpr/brunswik/notes/essay1.html">https://www.albany.edu/cpr/brunswik/notes/essay1.html</a> (1998)</li><li>Fan, S., Dal Monte, O., Chang, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Levels+of+naturalism+in+social+neuroscience+research.">Levels of naturalism in social neuroscience research.</a> IScience. 24 (7), 102702 (2021).</li><li>Orban, G. A., Lanzilotto, M., Bonini, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=From+observed+action+identity+to+social+affordances.">From observed action identity to social affordances.</a> Trends in Cognitive Sciences. 25 (6), 493-505 (2021).</li><li>Gray, H. M., Gray, K., Wegner, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dimensions+of+mind+perception.">Dimensions of mind perception.</a> Science. 315 (5812), 619 (2007).</li><li>Li, Z., Terfurth, L., Woller, J. P., Wiese, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mind+the+machines:+Applying+implicit+measures+of+mind+perception+to+social+robotics.">Mind the machines: Applying implicit measures of mind perception to social robotics.</a> 2022 17th ACM/IEEE International Conference on Human-Robot Interaction (HRI. , 236-245 (2022).</li><li>Karpinski, A., Steinman, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+single+category+implicit+association+test+as+a+measure+of+implicit+social+cognition.">The single category implicit association test as a measure of implicit social cognition.</a> Journal of Personality and Social Psychology. 91 (1), 16 (2006).</li><li>Greenwald, A. G., McGhee, D. E., Schwartz, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+individual+differences+in+implicit+cognition:+the+implicit+association+test.">Measuring individual differences in implicit cognition: the implicit association test.</a> Journal of Personality and Social Psychology. 74 (6), 1464 (1998).</li><li>Freeman, J. B., Ambady, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MouseTracker:+Software+for+studying+real-time+mental+processing+using+a+computer+mouse-tracking+method.">MouseTracker: Software for studying real-time mental processing using a computer mouse-tracking method.</a> Behavior Research Methods. 42 (1), 226-241 (2010).</li><li>Pek&#231;etin, T. N., Barinal, B., Tun&#231;, J., Acarturk, C., Urgen, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studying+mind+perception+in+social+robotics+implicitly:+The+need+for+validation+and+norming.">Studying mind perception in social robotics implicitly: The need for validation and norming.</a> Proceedings of the 2023 ACM/IEEE International Conference on Human-Robot Interaction. , 202-210 (2023).</li><li>Yu, Z., Wang, F., Wang, D., Bastin, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beyond+reaction+times:+Incorporating+mouse-tracking+measures+into+the+implicit+association+test+to+examine+its+underlying+process.">Beyond reaction times: Incorporating mouse-tracking measures into the implicit association test to examine its underlying process.</a> Social Cognition. 30 (3), 289-306 (2012).</li><li>Romero, C. A., Snow, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+for+presenting+real-world+objects+under+controlled+laboratory+conditions.">Methods for presenting real-world objects under controlled laboratory conditions.</a> Journal of Visualized Experiments. (148), e59762 (2019).</li><li>Jastorff, J., Abdollahi, R. O., Fasano, F., Orban, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Seeing+biological+actions+in+3+D:+An+f+MRI+study.">Seeing biological actions in 3 D: An f MRI study.</a> Human Brain Mapping. 37 (1), 203-219 (2016).</li><li>Ferri, S., Pauwels, K., Rizzolatti, G., Orban, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereoscopically+observing+manipulative+actions.">Stereoscopically observing manipulative actions.</a> Cerebral Cortex. 26 (8), 3591-3610 (2016).</li><li>Stangl, M., Maoz, S. L., Suthana, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mobile+cognition:+Imaging+the+human+brain+in+the+'real+world.">Mobile cognition: Imaging the human brain in the 'real world.</a> Nature Reviews Neuroscience. 24 (6), 347-362 (2023).</li><li>Kriegeskorte, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deep+neural+networks:+a+new+framework+for+modeling+biological+vision+and+brain+information+processing.">Deep neural networks: a new framework for modeling biological vision and brain information processing.</a> Annual Review of Vision Science. 1, 417-446 (2015).</li><li>Marblestone, A. H., Wayne, G., Kording, K. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toward+an+integration+of+deep+learning+and+neuroscience.">Toward an integration of deep learning and neuroscience.</a> Frontiers in Computational Neuroscience. 10, 94 (2016).</li></ol>

The authors declare that they have no relevant or material financial interests related to the research described in this article.

The overarching goal of the present study is to contribute to our understanding of how human high-level visual perception and cognition work in real-life situations. This study focused on action perception and suggested a naturalistic yet controllable experimental paradigm that enables researchers to test how individuals perceive and evaluate others&#39; actions by presenting real actors in a laboratory setting.
The significance of this proposed methodology compared to existing methodologies i...

A fundamental skill for survival and social interaction is the ability to perceive and make sense of others&#39; actions and interact with them in the surrounding environment. Previous research in the last several decades has made significant contributions to understanding the fundamental principles of how individuals perceive and understand others&#39; actions1,2,3,4,5,6,7,8,9,10,11. Nevertheless, given the complexity of interactions and the circumstances in which they occur, there is an obvious need to further develop the body of knowledge in naturalistic settings in order to reach a more complete understanding of this complex skill in daily life settings.
In natural environments such as our daily life settings, perception and cognition exhibit embodied, embedded, extended, and enactive characteristics12. In contrast to internalist accounts of brain functions that tend to understate the roles of the body and the environment, contemporary approaches to embodied cognition focus on the dynamic coupling of the brain, body, and environment. On the other hand, most social psychology, cognitive psychology, and neuroscience research on action perception tend to assume that utilizing well-controlled and simplified experiment designs in laboratory conditions (e.g., images or videos in computerized tasks) yields results that can be generalized to more complex scenarios such as real-world interactions1,2,3,4,5,6,7,8,9,10,11. This assumption guarantees that robust and reliable data can be obtained under many circumstances. Nevertheless, a well-known challenge is that the validity of the models derived from carefully controlled experiments is limited when tested in a real-world context13. Consequently, further investigations13,14,15,16,17,18,19,20,21,22 have been conducted to address the ecological and external validity of stimuli and experimental designs in various fields of research.
In this study, a novel method is suggested for investigating how individuals perceive and evaluate others&#39; actions by using live actions performed by a real, physically present actor. Scenarios similar to real-life contexts are employed, while the experimenters have control over possible confounding factors. This study is a form of &#34;naturalistic laboratory research&#34;, within the framework of Matusz et al.14&#160;which can be conceived as an intermediate stage between &#34;classic laboratory research&#34;, which makes use of maximal control over the stimuli and environment, often at the expense of naturalness, and &#34;fully naturalistic real-world research&#34;, which aims to maximize naturalness at the expense of control over the stimulation and the environment14. The study aims to address the need for empirical investigations at this level in action perception research in order to bridge the gap between the findings obtained in traditional laboratory experiments with a high degree of experimental control and the findings obtained in studies conducted in entirely unconstrained, natural settings.
Controlled versus unconstrained experiments 
Experimental control is an efficient strategy for designing experiments to test a specific hypothesis, as it allows researchers to isolate target variables from likely confounding factors. It also allows for revisiting the same hypothesis with certain levels of amendments, such as using slightly or totally different stimuli in the same design or testing the same stimuli in alternative experimental setups. Systematic investigation through controlled experiments is a traditional form of methodology in research in cognitive science and relevant domains. Controlled experiments still help to establish the body of knowledge on the fundamental principles of cognitive processes in various domains of research, such as attention, memory, and perception. However, recent research has also acknowledged the limitations of traditional laboratory experiments in terms of generalizing the findings to real-world settings, and researchers have been encouraged to conduct studies in enhanced ecological settings13,14,15,16,17,18,19,20,21. This shift aims to address two important issues regarding the discrepancy between traditional laboratory experiments and real-world settings. First, the world outside the laboratory is less deterministic than in experiments, which limits the representative power of systematic experimental manipulations. Second, the human brain is highly adaptive, and this is often underestimated due to the practical limitations of designing and conducting experimental studies22. The concept of &#34;ecological validity&#34;23,24 has been used to address methods for resolving this issue. The term is usually used to refer to a prerequisite for the generalization of experimental findings to the real world outside the laboratory context. Ecological validity has also been interpreted as referring to validating virtually naturalistic experimental setups with unconstrained stimuli to ensure that the study design is analogous to real-life scenarios25. Due to the high degree of variance in the interpretation of this term, an understanding of the advantages and limitations of alternative methodologies and stimulus selection is required.
Levels of naturalism in stimuli and experiment design 
Previous work in experimental psychology and cognitive neuroscience has used a wide range of stimuli with different levels of naturalism26. Most researchers prefer to use static images or short dynamic videos because these stimuli are easier to prepare than those that could simulate a real action or an event. Despite having advantages, these stimuli do not allow researchers to measure contingent behaviors among social agents. In other words, they are not actable and do not have social affordance27. In recent years, an alternative to these non-interactive stimuli has been developed: real-time animations of virtual avatars. These avatars allow for the investigation of the interactions between avatars and their users. However, the use of virtual avatars is subject to reduced user apprehension, especially when they do not appear particularly engaging in terms of their realistic and contingent behaviors26. Therefore, there is now more interest in using real social stimuli in experimental studies. Although their design, data recording, and analysis may require advanced equipment and complex data analysis, they are the best candidates for understanding naturalistic human behavior and cognition.
The present study proposes a methodology for using real-life social stimuli in a laboratory environment. This study aims to investigate how people perceive and evaluate others&#39; actions in a setting with enhanced ecological validity compared to traditional laboratory experiments. We have developed and described a novel setup in which participants are exposed to real actors who are physically present and share the same environment with them. In this protocol, the participants&#39; response times and mouse trajectories are measured, which requires precise timing of the stimuli presentation and strict control over the experimental conditions in this enhanced ecological setting. Therefore, the experimental paradigm stands out among the frameworks present in the literature since the naturalness of the stimuli is maximized without sacrificing control over the environment. Below, the protocol presents the steps to establish such a system and then continues with the representative results for the sample data. Finally, a discussion of the paradigm&#39;s significance, limitations, and plans for modifications is presented.
Experimental design 
Before proceeding to the protocol section, we describe the parameters used in the present study and present the details of the stimuli together with the experimental design.
Parameters in the study 
This study aims to measure how the type of actor and the class of actions they perform affect the mind perception processes of the participants. In the protocol, the mind perception process is measured in two main dimensions, namely agency and experience, as proposed by previous research28. The high and low ends of these two dimensions are also included, as recently introduced by Li et al.29.
The structure of the study was inspired by the single-category version30 of the commonly used implicit association task (IAT)31. In this task, the response times of the participants while they match an attribute concept with the target concept are used as an indication of the strength of their implicit associations for these two concepts. In the adaptation of this implicit task, the participants are presented live actions performed by real actors and required to match them to&#160;target concepts. The target concepts are the high and low ends of the agency or experience dimensions, depending on the block of the experiment.
To summarize, the independent variables are Actor Type and Action Class. Actor Type has two levels (i.e., two different actors, Actor1 and Actor2, performing in the study). Action Class has two levels: Action Class1 and Action Class2, and each class contains four actions. The participants evaluate the two actors separately in four blocks (one actor in each block), and in each block, the actors perform all of the actions in a counter-balanced order. The participants perform evaluations with respect to two pre-defined and forced dimensions: Agency and Experience. The four blocks in the experiment are (1) Actor1 in Agency Block, (2) Actor2 in Agency Block, (3) Actor1 in Experience Block, and (4) Actor2 in Experience Block. The order of the blocks is also counter-balanced among the participants so that the blocks with the same agent never follow each other.
Besides the answers of the participants, the response times and the x-y coordinates of the wireless mouse they use while they move toward one of the two response alternatives are recorded. So, the dependent variables are the response and the response time (RT) of the participants, as well as the measurements of maximum deviation (MD) and area under the curve (AUC), derived from the computer mouse-tracking. The variable response is categorical; it can be High or Low, and since the evaluations are done in one of the given blocks, the responses can also be labeled as High-Agency, Low-Agency, High-Experience, or Low-Experience. Response time is a continuous variable; its unit is seconds, and it refers to the elapsed time between the start of the presentation of an action and the occurrence of a mouse click on one of the response alternatives. The MD of a trajectory is a continuous variable, and it refers to the largest perpendicular deviation between the trajectory of the participant(s) and the idealized trajectory (straight line). The AUC of a trajectory is also a continuous variable, and it refers to the geometric area between the trajectory of the participant(s) and the idealized trajectory32.
Stimuli and design of the experiment 
A three-staged experiment is used in the present study. The measurements from the third part are used for the analyses; the first two parts serve as preparation for the final part. Below, we describe each part of the experiment together with the experimental stimuli and hypotheses.
In Experiment Part 1 (lexical training part), the participants complete a training session to understand the concepts of Agency and Experience and the capacity levels represented with the words High and Low. To select the concepts (n = 12) to be used in this training session, some of the authors of the current work conducted a normative study33. Since the present study was planned to be conducted in the native languages of the participants, the concepts were also translated into Turkish before being normalized. Concepts were selected from among those that were strongly associated with the High (n= 3) and Low (n= 3) ends of the two dimensions (six concepts for each). This part is crucial since the participants&#39; understanding of the concepts is expected to guide their evaluation processes.
In Experiment Part 2 (action identification part), participants watch the same eight actions performed by Actor1 and Actor2 one after the other and report what the action is to the experimenter. This section serves as a manipulation check; by presenting all the actions when both actors are performing them, it is possible to make sure that the participants understand the actions and are familiar with the actors before they start the implicit test, where they need to make fast evaluations. The actions selected for Action Class1 and Action Class2 are those that had the highest H scores and confidence levels (four different action exemplars in each action class) according to the results of the two normative studies (N = 219) for each actor condition conducted by some of the authors (manuscript in preparation). All actions are performed within an equal time duration of 6 s.
This is an ongoing study, and it has some other components; however, the hypotheses for the sections described above are as follows: (i) the type of actor will affect the dependent variables; Actor2 will yield longer RTs, higher MDs, and larger AUCs compared to Actor1; (ii) the type of action will affect the dependent measurements; Action Class1 will yield longer RTs, higher MDs, and larger AUCs compared to Action Class2; (iii) the dependent measurements for High and Low responses for the same actor and action class will differ across the block dimensions: Agency and Experience.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Adjustable Height Table</td>
			<td>Custom-made</td>
			<td>N/A</td>
			<td>Width: 60 cm, Height: 62 cm, Depth: 40 cm</td>
		</tr>
		<tr>
			<td>Ardunio UNO&#160;</td>
			<td>Smart Projects</td>
			<td>A000066</td>
			<td>Microcontroller used for switching the state of the LEDs from the script running on the operator PC</td>
		</tr>
		<tr>
			<td>Black Pants</td>
			<td>No brand</td>
			<td>N/A</td>
			<td>Relaxed-fit pants of actors with no apparent brand name or logo.</td>
		</tr>
		<tr>
			<td>Case</td>
			<td>Xigmatek</td>
			<td>EN43224</td>
			<td>XIGMATEK HELIOS RAINBOW LED USB 3.0 MidT ATX GAMING CASE</td>
		</tr>
		<tr>
			<td>CPU</td>
			<td>AMD</td>
			<td>YD1600BBAFBOX</td>
			<td>AMD Ryzen 5 1600 Soket AM4 3.2 GHz - 3.6 GHz 16 MB 65 W 12 nm Processor</td>
		</tr>
		<tr>
			<td>Curtains</td>
			<td>Custom-made</td>
			<td>N/A</td>
			<td>Width: Part 1: 110 cm width from the wall (left) side, Part 2: 123 cm width above OLED display, Part 3: 170 cm from OLED display to right side, Cabin depth: 100 cm, Inside cabin depth: 100 cm, all heights 230 cm except for Part 2 (75 cm height)</td>
		</tr>
		<tr>
			<td>Experimenter Adjustable/Swivel Chair</td>
			<td>No brand</td>
			<td>N/A</td>
			<td>Any brand</td>
		</tr>
		<tr>
			<td>Experimenter Table</td>
			<td>Custom</td>
			<td>N/A</td>
			<td>Width: 160 cm, Height: 75 cm, Depth: 80 cm</td>
		</tr>
		<tr>
			<td>GPU</td>
			<td>MSI</td>
			<td>GT 1030 2GHD4 LP OC</td>
			<td>MSI GEFORCE GT 1030 2GHD4 LP OC 2GB DDR4 64bit NVIDIA GPU</td>
		</tr>
		<tr>
			<td>Grey-color blackout curtain</td>
			<td>Custom-made</td>
			<td>N/A</td>
			<td>Width: 330 cm, Height: 230 cm, used for covering the background</td>
		</tr>
		<tr>
			<td>Hard Disk</td>
			<td>Kioxia</td>
			<td>LTC10Z240GG8</td>
			<td>Kioxia 240 GB Exceria Sata 3.0 SSD (555 MB Read/540 MB Write)</td>
		</tr>
		<tr>
			<td>Hard Disk</td>
			<td>Toshiba</td>
			<td>HDWK105UZSVA</td>
			<td>Toshiba 2,5&#39;&#39; 500 GB L200 SATA 3.0 8 MB Cache 5400 Rpm 7 mm Harddisk</td>
		</tr>
		<tr>
			<td>High-Power MOSFET Module</td>
			<td>N/A</td>
			<td>N/A</td>
			<td>Heating Controller MKS MOSFET Module</td>
		</tr>
		<tr>
			<td>Laptop</td>
			<td>Apple</td>
			<td>S/N: C02P916ZG3QT</td>
			<td>MacBook Pro 11.1 Intel Core i7 (Used as the actor PC)</td>
		</tr>
		<tr>
			<td>Laptop</td>
			<td>Asus&#160;</td>
			<td>UX410U</td>
			<td>Used for monitoring the security camera in real-time.</td>
		</tr>
		<tr>
			<td>LED lights</td>
			<td>No brand</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>LED Strip Power Supply</td>
			<td>No brand</td>
			<td>N/A</td>
			<td>AC to DC voltage converter used for supplying DC voltage to the lighting circuit</td>
		</tr>
		<tr>
			<td>MATLAB&#160;</td>
			<td>The MathWorks Inc., Natick, MA, USA</td>
			<td>Version: R2022a</td>
			<td>Used for programming the experiment. 
			 
			Required Toolboxes: 
			MATLAB Support Package for Arduino Hardware (version 22.1.2) 
			Instrument Control Toolbox (version 4.6) 
			Psychtoolbox (version 3)</td>
		</tr>
		<tr>
			<td>Monitor</td>
			<td>Philips</td>
			<td>UHB2051005145&#160;</td>
			<td>Model ID: 242V8A/00, PHILIPS 23.8&#34; 242V8A 4ms 75 Hz Freesync DP-HDMI+VGA IPS Gaming Monitor&#160;</td>
		</tr>
		<tr>
			<td>Motherboard</td>
			<td>MSI</td>
			<td>B450M-A PRO MAX</td>
			<td>MSI B450M-A PRO MAX Amd B450 Socket AM4 DDR4 3466(OC) M.2 Motherboard</td>
		</tr>
		<tr>
			<td>Mouse Pad for participant</td>
			<td>Monster</td>
			<td>&#160;78185721101502042 / 8699266781857</td>
			<td>Pusat Gaming Mouse Pad XL</td>
		</tr>
		<tr>
			<td>Night lamp</td>
			<td>Aukes</td>
			<td>ES620-0.5W 6500K-IP 20</td>
			<td>Used for helping the actors see around when the lights are off in the backstage.</td>
		</tr>
		<tr>
			<td>Participant Adjustable/Swivel Chair</td>
			<td>No brand</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Participant Table</td>
			<td>IKEA</td>
			<td>Sandsberg 294.203.93</td>
			<td>Width: 110 cm, Height: 75 cm, Depth: 67 cm</td>
		</tr>
		<tr>
			<td>Power Extension Cable</td>
			<td>Viko</td>
			<td>9011760Y</td>
			<td>250 V (6 inlets) Black</td>
		</tr>
		<tr>
			<td>Power Extension Cable</td>
			<td>Viko</td>
			<td>9011730Y</td>
			<td>250 V (3 inlets) Black</td>
		</tr>
		<tr>
			<td>Power Extension Cable</td>
			<td>Viko</td>
			<td>9011330Y</td>
			<td>250 V (3 inlets) White</td>
		</tr>
		<tr>
			<td>Power Extension Cable</td>
			<td>s-link&#160;</td>
			<td>Model No: SPG3-J-10</td>
			<td>AC - 250 V 3 meter (5 inlets)</td>
		</tr>
		<tr>
			<td>Power Supply</td>
			<td>THERMALTAKE</td>
			<td>PS-LTP-0550NHSANE-1</td>
			<td>THERMALTAKE LITEPOWER RGB 550W APFC 12 cm FAN PSU</td>
		</tr>
		<tr>
			<td>Professional Gaming Mouse</td>
			<td>Rampage</td>
			<td>8680096</td>
			<td>Model No: SMX-R50&#160;</td>
		</tr>
		<tr>
			<td>RAM</td>
			<td>GSKILL</td>
			<td>F4-3000C16S-8GVRB</td>
			<td>GSKILL 8GB (1x8GB) RipjawsV Red DDR4 3000 MHz CL16 1.35 V Single Ram</td>
		</tr>
		<tr>
			<td>Reception bell</td>
			<td>No brand</td>
			<td>N/A</td>
			<td>Used for helping the communication between the experimenter and the actors.</td>
		</tr>
		<tr>
			<td>Security Camera</td>
			<td>Brion Vega</td>
			<td>2-20204210</td>
			<td>Model:BV6000</td>
		</tr>
		<tr>
			<td>Speakers</td>
			<td>Logitech</td>
			<td>P/N: 880-000-405 PID: WD528XM</td>
			<td>Used for playing the background music.</td>
		</tr>
		<tr>
			<td>Survey Software</td>
			<td>Qualtrics&#160;</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Switching Module</td>
			<td>No brand</td>
			<td>N/A</td>
			<td>F5305S PMOS Switch Module</td>
		</tr>
		<tr>
			<td>Table under the OLED display</td>
			<td>Custom-made</td>
			<td>N/A</td>
			<td>Width: 123 cm, Height: 75 cm, Depth: 50 cm</td>
		</tr>
		<tr>
			<td>Transparent OLED Display</td>
			<td>Planar</td>
			<td>PN: 998-1483-01 S/N:195210075</td>
			<td>A 55-inch transparent display that showcases dynamic information, enabled the opaque and transparent usage during the experiment.</td>
		</tr>
		<tr>
			<td>UPS</td>
			<td>EAG</td>
			<td>K200610100087</td>
			<td>EAG 110</td>
		</tr>
		<tr>
			<td>UPS</td>
			<td>EAG</td>
			<td>210312030507</td>
			<td>EAG 103</td>
		</tr>
		<tr>
			<td>USB 2.0 Cable Type A/B for Arduino UNO (Blue)</td>
			<td>Smart Projects</td>
			<td>M000006&#160;</td>
			<td>Used to connect the microcontroller to the experimenter PC.</td>
		</tr>
		<tr>
			<td>USB to RS232 Converter&#160;</td>
			<td>s-link</td>
			<td>8680096082559</td>
			<td>Model: SW-U610</td>
		</tr>
		<tr>
			<td>White Long-Sleeved Blouse (2)</td>
			<td>H&#38;M (cotton)</td>
			<td>N/A</td>
			<td>Relaxed-fit blouses with a round neckline and without ant apparent brand name or logo.</td>
		</tr>
		<tr>
			<td>Wireless Keyboard</td>
			<td>Logitech</td>
			<td>P/N: 820-003488 S/N: 1719CE0856D8</td>
			<td>Model: K360</td>
		</tr>
		<tr>
			<td>Wireless Mouse</td>
			<td>Logitech</td>
			<td>S/N: 2147LZ96BGQ9</td>
			<td>Model: M190 (Used as the response device)</td>
		</tr>
	</tbody>
</table>

a naturalistic setup for presenting real people and live actions in experimental psychology and cognitive neuroscience studies

Perception of others&#39; actions is crucial for survival, interaction, and communication. Despite decades of cognitive neuroscience research dedicated to understanding the perception of actions, we are still far away from developing a neurally inspired computer vision system that approaches human action perception. A major challenge is that actions in the real world consist of temporally unfolding events in space that happen &#34;here and now&#34; and are actable. In contrast, visual perception and cognitive neuroscience research to date have largely studied action perception through 2D displays (e.g., images or videos) that lack the presence of actors in space and time, hence these displays are limited in affording actability. Despite the growing body of knowledge in the field, these challenges must be overcome for a better understanding of the fundamental mechanisms of the perception of others&#39; actions in the real world. The aim of this study is to introduce a novel setup to conduct naturalistic laboratory experiments with live actors in scenarios that approximate real-world settings. The core element of the setup used in this study is a transparent organic light-emitting diode (OLED) screen through which participants can watch the live actions of a physically present actor while the timing of their presentation is precisely controlled. In this work, this setup was tested in a behavioral experiment. We believe that the setup will help researchers reveal fundamental and previously inaccessible cognitive and neural mechanisms of action perception and will be a foundation for future studies investigating social perception and cognition in naturalistic settings.

Response time (RT) comparisons 
The current study is an ongoing project, so, as representative results, data from the main part of the experiment (Experiment Part 3) are presented. These data are from 40 participants, including 23 females and 17 males, with ages ranging from 18-28 years (M = 22.75, SD = 3.12).
Investigating the extent of the normality of the distribution of the dependent variables was necessary in order to choose the appropriate statisti...

Watch this Scientific Journal Video about A Novel Setup to Conduct Naturalistic Laboratory Experiments with Real Human Actors in Scenarios at JoVE.com

Author Spotlight: A Novel Setup to Conduct Naturalistic Laboratory Experiments with Real Human Actors in Scenarios 

This study presents a naturalistic experimental setup that allows researchers to present real-time action stimuli, obtain response time and mouse tracking data while participants respond after each stimulus display, and change actors between experimental conditions with a unique system including a special transparent organic light-emitting diode (OLED) screen and light manipulation.

A Naturalistic Setup for Presenting Real People and Live Actions in Experimental Psychology and Cognitive Neuroscience Studies

Perception of others&#39; actions is crucial for survival, interaction, and communication. Despite decades of cognitive neuroscience research dedicated to ...

a-naturalistic-setup-for-presenting-real-people-live-actions

Research

JoVE Journal

Neuroscience

1.8K Views.  Middle East Technical University. This study presents a naturalistic experimental setup that allows researchers to present real-time action stimuli, obtain response time and mouse tracking data while participants respond after each stimulus display, and change actors between experimental conditions with a unique system including a special transparent organic light-emitting diode (OLED) screen and light manipulation.

Video: Author Spotlight: A Novel Setup to Conduct Naturalistic Laboratory Experiments with Real Human Actors in Scenarios 

High Density Event-related Potential  Data Acquisition in Cognitive Neuroscience

Functional magnetic resonance imaging (fMRI) is currently the standard method of evaluating brain function in the field of Cognitive Neuroscience, in part because fMRI data acquisition and analysis techniques are readily available. Because fMRI has excellent spatial resolution but poor temporal resolution, this method can only be used to identify the spatial location of brain activity associated with a given cognitive process (and reveals virtually nothing about the time course of brain activity). By contrast, event-related potential (ERP) recording, a method that is used much less frequently than fMRI, has excellent temporal resolution and thus can track rapid temporal modulations in neural activity. Unfortunately, ERPs are under utilized in Cognitive Neuroscience because data acquisition techniques are not readily available and low density ERP recording has poor spatial resolution. In an effort to foster the increased use of ERPs in Cognitive Neuroscience, the present article details key techniques involved in high density ERP data acquisition. Critically, high density ERPs offer the promise of excellent temporal resolution and good spatial resolution (or excellent spatial resolution if coupled with fMRI), which is necessary to capture the spatial-temporal dynamics of human brain function.

Event-related potential (ERP) recording is under utilized in Cognitive Neuroscience because data acquisition techniques are not readily available and this method often has poor spatial resolution. To foster the increased use of ERPs in Cognitive Neuroscience, the present article details key techniques involved in high density ERP data acquisition.

Functional magnetic resonance imaging (fMRI) is currently the standard method of evaluating brain function in the field of Cognitive Neuroscience, in part ...

Assessing Burrowing, Nest Construction, and Hoarding in Mice

Deterioration in the ability to perform "Activities of daily living" (ADL) is an early sign of Alzheimer's disease (AD). Preclinical behavioural screening of possible treatments for AD currently largely focuses on cognitive testing, which frequently demands expensive equipment and lots of experimenter time. However, human episodic memory (the most severely affected aspect of memory in AD) is different to rodent memory, which seems to be largely non-episodic. Therefore the present ways of screening for new AD treatments for AD in rodents are intrinsically unlikely to succeed. A new approach to preclinical screening would be to characterise the ADL of mice. Fortuitously, several such assays have recently been developed at Oxford, and here the three most sensitive and well-characterised are presented.
Burrowing was first developed in Oxford13. It evolved from a need to develop a mouse hoarding paradigm. Most published rodent hoarding paradigms required a distant food source to be linked to the home cage by a connecting passage. This would involve modifying the home cage as well as making a mouse-proof connecting passage and food source. So it was considered whether it would be possible to put the food source inside the cage. It was found that if a container was placed on the floor it was emptied by the next morning., The food pellets were, however, simply deposited in a heap at the container entrance, rather than placed in a discrete place away from the container, as might be expected if the mice were truly hoarding them. Close inspection showed that the mice were performing digging ("burrowing") movements, not carrying the pellets in their mouths to a selected place as they would if truly hoarding them.6



Food pellets are not an essential substrate for burrowing; mice will empty tubes filled with sand, gravel, even soiled bedding from their own cage. Moreover, they will empty a full tube even if an empty one is placed next to it8.



Several nesting protocols exist in the literature. The present Oxford one simplifies the procedure and has a well-defined scoring system for nest quality5. 



A hoarding paradigm was later developed in which the mice, rather than hoarding back to the real home cage, were adapted to living in the "home base" of a hoarding apparatus. This home base was connected to a tube made of wire mesh, the distal end of which contained the food source. This arrangement proved to yield good hoarding behaviour, as long as the mice were adapted to living in the "home base" during the day and only allowed to enter the hoarding tube at night.

Burrowing, nesting, and hoarding are species-typical activities that mice readily perform in the laboratory. This article describes how they can be easily and cheaply assessed. These protocols are extremely sensitive to mouse strain, brain lesions and diseases. Moreover they constitute &#x201C;environmental enrichment&#x201D; for the mice, and embody the &#x201C;Refinement&#x201D; aspect of the &#x201C;3 Rs&#x201D;18.

Deterioration in the ability to perform "Activities of daily living" (ADL) is an early sign of Alzheimer's disease (AD). Preclinical behavioural screening ...

Hyponeophagia: A Measure of Anxiety in the Mouse

Before the present day, when fast-acting and potent rodenticides such as alpha-chloralose were not yet in use, the work of pest controllers was often hampered by a phenomenon known as "bait shyness". Mice and rats cannot vomit, due to the tightness of the cardiac sphincter of the stomach, so to overcome the problem of potential food toxicity they have evolved a strategy of first ingesting only very small amounts of novel substances. The amounts ingested then gradually increase until the animal has determined whether the substance is safe and nutritious. So the old rat-catchers would first put a palatable substance such as oatmeal, which was to be the vehicle for the toxin, in the infested area. Only when large amounts were being readily consumed would they then add the poison, in amounts calculated not to affect the taste of the vehicle. The poisoned bait, which the animals were now readily eating in large amounts, would then swiftly perform its function.
Bait shyness is now used in the behavioural laboratory as a way of measuring anxiety. A highly palatable but novel substance, such as sweet corn, nuts or sweetened condensed milk, is offered to the mice (or rats) in a novel situation, such as a new cage. The latency to consume a defined amount of the new food is then measured.
Robert M.J. Deacon can be reach at <a href="mailto:robert.deacon@psy.ox.ac.uk">robert.deacon@psy.ox.ac.uk</a>

Mice and rats, due to their innate cautiousness, are initially slow in consuming a novel food, particularly in a novel place. This hyponeophagia can readily be measured in the laboratory, even though laboratory animals are much less anxious than their wild counterparts

Before the present day, when fast-acting and potent rodenticides such as alpha-chloralose were not yet in use, the work of pest controllers was often ...

A General Method for Evaluating Incubation of Sucrose Craving in Rats

For someone on a food-restricted diet, food craving in response to food-paired cues may serve as a key behavioral transition point between abstinence and relapse to food taking 1. Food craving conceptualized in this way is akin to drug craving in response to drug-paired cues. A rich literature has been developed around understanding the behavioral and neurobiological determinants of drug craving; we and others have been focusing recently on translating techniques from basic addiction research to better understand addiction-like behaviors related to food 2-4.
As done in previous studies of drug craving, we examine sucrose craving behavior by utilizing a rat model of relapse. In this model, rats self-administer either drug or food in sessions over several days. In a session, lever responding delivers the reward along with a tone+light stimulus. Craving behavior is then operationally defined as responding in a subsequent session where the reward is not available. Rats will reliably respond for the tone+light stimulus, likely due to its acquired conditioned reinforcing properties 5. This behavior is sometimes referred to as sucrose seeking or cue reactivity. In the present discussion we will use the term "sucrose craving" to subsume both of these constructs.
In the past decade, we have focused on how the length of time following reward self-administration influences reward craving. Interestingly, rats increase responding for the reward-paired cue over the course of several weeks of a period of forced-abstinence. This "incubation of craving" is observed in rats that have self-administered either food or drugs of abuse 4,6. This time-dependent increase in craving we have identified in the animal model may have great potential relevance to human drug and food addiction behaviors.
Here we present a protocol for assessing incubation of sucrose craving in rats. Variants of the procedure will be indicated where craving is assessed as responding for a discrete sucrose-paired cue following extinction of lever pressing within the sucrose self-administration context (Extinction without cues) or as responding for sucrose-paired cues in a general extinction context (Extinction with cues).

Responding for food or drug-paired cues increases over the course of a period of abstinence and this may relate to an increased susceptibility to relapse behaviors. Here we detail a procedure for evaluating this "incubation of craving" in rats that have self-administered sucrose.

For someone on a food-restricted diet, food craving in response to food-paired cues may serve as a key behavioral transition point between abstinence and ...

A Low Cost Setup for Behavioral Audiometry in Rodents

In auditory animal research it is crucial to have precise information about basic hearing parameters of the animal subjects that are involved in the experiments. Such parameters may be physiological response characteristics of the auditory pathway, e.g. via brainstem audiometry (BERA). But these methods allow only indirect and uncertain extrapolations about the auditory percept that corresponds to these physiological parameters. To assess the perceptual level of hearing, behavioral methods have to be used. A potential problem with the use of behavioral methods for the description of perception in animal models is the fact that most of these methods involve some kind of learning paradigm before the subjects can be behaviorally tested, e.g. animals may have to learn to press a lever in response to a sound. As these learning paradigms change perception itself 1,2 they consequently will influence any result about perception obtained with these methods and therefore have to be interpreted with caution. Exceptions are paradigms that make use of reflex responses, because here no learning paradigms have to be carried out prior to perceptual testing. One such reflex response is the acoustic startle response (ASR) that can highly reproducibly be elicited with unexpected loud sounds in na&iuml;ve animals. This ASR in turn can be influenced by preceding sounds depending on the perceptibility of this preceding stimulus: Sounds well above hearing threshold will completely inhibit the amplitude of the ASR; sounds close to threshold will only slightly inhibit the ASR. This phenomenon is called pre-pulse inhibition (PPI) 3,4, and the amount of PPI on the ASR gradually depends on the perceptibility of the pre-pulse. PPI of the ASR is therefore well suited to determine behavioral audiograms in na&iuml;ve, non-trained animals, to determine hearing impairments or even to detect possible subjective tinnitus percepts in these animals. In this paper we demonstrate the use of this method in a rodent model (cf. also ref. 5), the Mongolian gerbil (Meriones unguiculatus), which is a well know model species for startle response research within the normal human hearing range (e.g. 6).

A fast and inexpensive method for the behavioral determination of hearing parameters like hearing thresholds, hearing impairments or phantom perceptions (subjective tinnitus) is described. It uses pre-pulse inhibition of the acoustic startle response and can be easily implemented in a personal computer using a programmable AD/DA-converter and a piezo sensor.

In auditory animal research it is crucial to have precise information about basic hearing parameters of the animal subjects that are involved in the ...

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents

When rodents have free access to a running wheel in their home cage, voluntary use of this wheel will depend on the time of day1-5. Nocturnal rodents, including rats, hamsters, and mice, are active during the night and relatively inactive during the day. Many other behavioral and physiological measures also exhibit daily rhythms, but in rodents, running-wheel activity serves as a particularly reliable and convenient measure of the output of the master circadian clock, the suprachiasmatic nucleus (SCN) of the hypothalamus. In general, through a process called entrainment, the daily pattern of running-wheel activity will naturally align with the environmental light-dark cycle (LD cycle; e.g. 12 hr-light:12 hr-dark). However circadian rhythms are endogenously generated patterns in behavior that exhibit a ~24 hr period, and persist in constant darkness. Thus, in the absence of an LD cycle, the recording and analysis of running-wheel activity can be used to determine the subjective time-of-day. Because these rhythms are directed by the circadian clock the subjective time-of-day is referred to as the circadian time (CT). In contrast, when an LD cycle is present, the time-of-day that is determined by the environmental LD cycle is called the zeitgeber time (ZT).
Although circadian rhythms in running-wheel activity are typically linked to the SCN clock6-8, circadian oscillators in many other regions of the brain and body9-14 could also be involved in the regulation of daily activity rhythms. For instance, daily rhythms in food-anticipatory activity do not require the SCN15,16 and instead, are correlated with changes in the activity of extra-SCN oscillators17-20. Thus, running-wheel activity recordings can provide important behavioral information not only about the output of the master SCN clock, but also on the activity of extra-SCN oscillators. Below we describe the equipment and methods used to record, analyze and display circadian locomotor activity rhythms in laboratory rodents.

Circadian rhythms in voluntary wheel-running activity in mammals are tightly coupled to the molecular oscillations of a master clock in the brain. As such, these daily rhythms in behavior can be used to study the influence of genetic, pharmacological, and environmental factors on the functioning of this circadian clock.

When rodents have free access to a running wheel in their home cage, voluntary use of this wheel will depend on the time of day1-5. Nocturnal rodents, ...

Ex utero Electroporation and Whole Hemisphere Explants: A Simple Experimental Method for Studies of Early Cortical Development

Cortical development involves complex interactions between neurons and non-neuronal elements including precursor cells, blood vessels, meninges and associated extracellular matrix. Because they provide a suitable organotypic environment, cortical slice explants are often used to investigate those interactions that control neuronal differentiation and development. Although beneficial, the slice explant model can suffer from drawbacks including aberrant cellular lamination and migration. Here we report a whole cerebral hemisphere explant system for studies of early cortical development that is easier to prepare than cortical slices and shows consistent organotypic migration and lamination. In this model system, early lamination and migration patterns proceed normally for a period of two days in vitro, including the period of preplate splitting, during which prospective cortical layer six forms. We then developed an ex utero electroporation (EUEP) approach that achieves ~80% success in targeting GFP expression to neurons developing in the dorsal medial cortex.
The whole hemisphere explant model makes early cortical development accessible for electroporation, pharmacological intervention and live imaging approaches. This method avoids the survival surgery required of in utero electroporation (IUEP) approaches while improving both transfection and areal targeting consistency. This method will facilitate experimental studies of neuronal proliferation, migration and differentiation.

Ex utero Electroporation and Whole Hemisphere Explants: A Simple Experimental Method for Studies of Early Cortical Development

This protocol describes an improved explant procedure that involves ex utero electroporation, dissection and culture of entire cerebral hemispheres from the embryonic mouse. The preparation facilitates pharmacological studies and assays of gene function during early cortical development.

Cortical development involves complex interactions between neurons and non-neuronal elements including precursor cells, blood vessels, meninges and ...

Simultaneous Detection of c-Fos Activation from Mesolimbic and Mesocortical Dopamine Reward Sites Following Naive Sugar and Fat Ingestion in Rats

This study uses cellular c-fos activation to assess effects of novel ingestion of fat and sugar on brain dopamine (DA) pathways in rats. Intakes of sugars and fats are mediated by their innate attractions as well as learned preferences. Brain dopamine, especially meso-limbic and meso-cortical projections from the ventral tegmental area (VTA), has been implicated in both of these unlearned and learned responses. The concept of distributed brain networks, wherein several sites and transmitter/peptide systems interact, has been proposed to mediate palatable food intake, but there is limited evidence empirically demonstrating such actions. Thus, sugar intake elicits DA release and increases c-fos-like immunoreactivity (FLI) from individual VTA DA projection zones including the nucleus accumbens (NAC), amygdala (AMY) and medial prefrontal cortex (mPFC) as well as the dorsal striatum. Further, central administration of selective DA receptor antagonists into these sites differentially reduce acquisition and expression of conditioned flavor preferences elicited by sugars or fats. One approach by which to determine whether these sites interacted as a distributed brain network in response to sugar or fat intake would be to simultaneous evaluate whether the VTA and its major mesotelencephalic DA projection zones (prelimbic and infralimbic mPFC, core and shell of the NAc, basolateral and central-cortico-medial AMY) as well as the dorsal striatum would display coordinated and simultaneous FLI activation after oral, unconditioned intake of corn oil (3.5%), glucose (8%), fructose (8%) and saccharin (0.2%) solutions. This approach is a successful first step in identifying the feasibility of using cellular c-fos activation simultaneously across relevant brain sites to study reward-related learning in ingestion of palatable food in rodents.

The goal of this study is to identify reward-related distributed brain networks by delineating a reliable immunohistological technique using cellular c-fos activation to measure simultaneous changes in dopamine pathways and terminal sites after novel ingestion of fat and sugar in rats.

This study uses cellular c-fos activation to assess effects of novel ingestion of fat and sugar on brain dopamine (DA) pathways in rats. Intakes of sugars ...

The Use of Trace Eyeblink Classical Conditioning to Assess Hippocampal Dysfunction in a Rat Model of Fetal Alcohol Spectrum Disorders

Neonatal rats were administered a relatively high concentration of ethyl alcohol (11.9% v/v) during postnatal days 4-9, a time when the fetal brain undergoes rapid organizational change and is similar to accelerated brain changes that occur during the third trimester in humans. This model of fetal alcohol spectrum disorders (FASDs) produces severe brain damage, mimicking the amount and pattern of binge-drinking that occurs in some pregnant alcoholic mothers. We describe the use of trace eyeblink classical conditioning (ECC), a higher-order variant of associative learning, to assess long-term hippocampal dysfunction that is typically seen in alcohol-exposed adult offspring. At 90 days of age, rodents were surgically prepared with recording and stimulating electrodes, which measured electromyographic (EMG) blink activity from the left eyelid muscle and delivered mild shock posterior to the left eye, respectively. After a 5 day recovery period, they underwent 6 sessions of trace ECC to determine associative learning differences between alcohol-exposed and control rats. Trace ECC is one of many possible ECC procedures that can be easily modified using the same equipment and software, so that different neural systems can be assessed. ECC procedures in general, can be used as diagnostic tools for detecting neural pathology in different brain systems and different conditions that insult the brain.

Trace eyeblink classical conditioning (ECC) was used to assess hippocampal-dependent associative learning in adult rats that were administered a high concentration (11.9% v/v) of alcohol during early neonatal brain development. In general, ECC procedures are sound diagnostic tools for detecting brain dysfunction across many psychological and biomedical settings.

Neonatal rats were administered a relatively high concentration of ethyl alcohol (11.9% v/v) during postnatal days 4-9, a time when the fetal brain ...

Whole-cell Currents Induced by Puff Application of GABA in Brain Slices

Pharmacological administration is commonly used when conducting whole-cell patch-clamp recording in brain slices. One of the best methods of drug application during electrophysiological recording is the puff technique, which can be used to study the effect of pharmacological reagents on neuronal activities in brain slices. The greatest advantage of puff application is that the drug concentration around the recording site increases rapidly, thus preventing desensitization of membrane receptors. Successful use of puff application involves careful attention to the following elements: the concentration of the drug, the parameters of the puff micropipette, the distance between the tip of a puff micropipette and the neuron recorded, and the duration and pressure driving the puff (pounds per square inch, psi). This article describes a step-by-step procedure for recording whole-cell currents induced by puffing gamma-aminobutyric acid (GABA) onto a neuron of a prefrontal cortical slice. Notably, the same procedure can be applied with minor modifications to other brain areas such as the hippocampus and the striatum, and to different preparations, such as cell cultures.

We describe the puff technique, by which pharmacological reagents can be administered during whole-cell patch-clamp recording, and highlight various aspects of the features that are crucial for its success.

A Naturalistic Setup for Presenting Real People and Live Actions in Experimental Psychology and Cognitive Neuroscience Studies

Summary

Explore More Videos

Chapters in this video

High Density Event-related Potential Data Acquisition in Cognitive Neuroscience

Assessing Burrowing, Nest Construction, and Hoarding in Mice

Hyponeophagia: A Measure of Anxiety in the Mouse

A General Method for Evaluating Incubation of Sucrose Craving in Rats

A Low Cost Setup for Behavioral Audiometry in Rodents

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents

Ex utero Electroporation and Whole Hemisphere Explants: A Simple Experimental Method for Studies of Early Cortical Development

Simultaneous Detection of c-Fos Activation from Mesolimbic and Mesocortical Dopamine Reward Sites Following Naive Sugar and Fat Ingestion in Rats

The Use of Trace Eyeblink Classical Conditioning to Assess Hippocampal Dysfunction in a Rat Model of Fetal Alcohol Spectrum Disorders

Whole-cell Currents Induced by Puff Application of GABA in Brain Slices