Name: a method for manipulating blood glucose and measuring resulting changes in cognitive accessibility of target stimuli
Uploaded: 2016-08-12T13:00:00
Description: Watch this Scientific Journal Video about A Method for Manipulating Blood Glucose and Measuring Resulting Changes in Cognitive Accessibility of Target Stimuli at JoVE.com

This research was conducted with grant funding from the Anthony M. Marchionne Foundation (70256-23284) and TCU IS. The authors thank Danielle DelPriore, Amanda Morin, and Christopher Rodeheffer for their helpful contributions towards shaping these methods.&#160;The authors would also like to thank Hannah Bradshaw and Randi Proffitt Leyva for their assistance with filming this protocol.

Ethics Statement: Procedures and incentives involving human subjects have been approved by the Institutional Review Board (IRB) at Texas Christian University.
1. Participant Inclusion Factors and Recruitment
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	<li>Exclude people who have sugar sensitivities or any other health condition, like diabetes or other conditions that impair glucoregulation, and that would preclude them from being able to safely consume a sugar sweetened or artificially sweetened beverage. Exclude participants wi...

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	<li>Smith, M. A., Riby, L. M., van Eekelen, J. A. M., Foster, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glucose+enhancement+of+human+memory:+A+comprehensive+research+review+of+the+glucose+memory+facilitation+effect.">Glucose enhancement of human memory: A comprehensive research review of the glucose memory facilitation effect.</a> Neurosci Biobehav Rev. 35, 770-783 (2011).</li><li>Meikle, A., Riby, L. M., Stollery, 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+impact+of+glucose+ingestion+and+gluco-regulatory+control+on+cognitive+performance:+A+comparison+of+younger+and+middle+aged+adults.">The impact of glucose ingestion and gluco-regulatory control on cognitive performance: A comparison of younger and middle aged adults.</a> Hum Psychopharm Clin. 19, 523-535 (2004).</li><li>Riby, L. 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This manuscript outlines a simple, inexpensive procedure for manipulating blood glucose, as well as a procedure for measuring resulting changes in the cognitive accessibility of target words and concepts. The above outlined methods can be applied to a wide range of research areas including social psychology, cognitive psychology, and nutrition sciences. Given that this method may be used by people in multiple research areas (some that do not typically use survey data), this section will present some tips on critical step...

Researchers in cognitive psychology and neuroscience have long studied the impact of blood glucose fluctuations on the brain, cognition, and behavior1. For example, researchers have found that fluctuations in blood glucose predict differences in memory (verbal, digit span, working, and episodic)1-5, attention6,7, puzzle solving8, and performance on tasks of varying levels of cognitive demand2,9,10. This research finds that increasing blood glucose enhances attention and memory, and that these effects are strongest when working on cognitively demanding tasks, and in those of older age1,3.
In recent decades, research on the impact of blood glucose fluctuations on human psychology has also become a topic of interest in the field of social psychology11-13. Fluctuations in blood glucose have been linked to changes in mood14, motivation15, self-control11-13, attitudes16,17, prejudice18, and to changes in decision-making in consumer19, eating20,21, and financial domains22. Because these results transcend a wide variety of dependent variables, the message about the role of blood glucose in decision-making is clear: blood glucose is the critical form of energy to the brain, and depletions in blood glucose lead to important changes in cognition and self regulation11,13,15.
Given the important role that blood glucose plays in various psychological and behavioral outcomes, the current manuscript offers a simple method for manipulating blood glucose that researchers can use for testing a range of cognitions and behaviors. Additionally, the current manuscript provides a method for assessing the cognitive accessibility of target words or concepts that may change in response to fluctuations in blood glucose using a lexical decision task. The efficiency of the present methods make them ideal for experimental research, as they effectively manipulate blood glucose and measure cognitive changes using relatively inexpensive, commercially-available products. The affordability of the present blood glucose manipulation makes it easier to run the large numbers of participants needed to obtain the adequate power needed to detect statistically significant differences in behavior caused by any manipulated changes in blood glucose23. Additionally, the lexical decision task is useful in that it can reveal implicit changes in cognition not easily accessed through more explicit measures such as self-report surveys24.
The described blood glucose manipulation task involves an 8 hour fasting period followed by the directed consumption of a caloric or a calorie-free drink22. After fasting for eight hours, participants are randomly assigned to consume either a sugar sweetened beverage or water. This method also allows for the testing of any unique effects produced by non-caloric sweeteners (e.g. aspartame, sucralose), which taste sweet like traditional caloric sweeteners, but do not contain the sugars needed to raise blood glucose levels20,22,25. If interested in the effects of non-calorically sweetened beverages, this task includes an optional, 3rd between-subjects condition in which participants consume a &#34;zero-calorie&#34; drink. The current method has been applied successfully in multiple social psychological paradigms12,18,22, and offers a shorter way to test for the effects of changes in blood glucose upon self-regulation than previously used measures like glucose tolerance tests26.
The authors also provide a procedure for assessing the cognitive accessibility of target words, or concepts, using a lexical decision task27,28. In this task, letter strings and words are presented via computer in rapid-fire format, and typically fall into a few distinct conceptual categories (in the described research, the categories were: high fat food words, low fat food words, non-words). Participants are asked to quickly identify (typically via keystroke) whether a string of letters (e.g. fhens; pizza) is a word or a non-word. The reaction speed in which participants correctly identify letter strings in each conceptual category measures the relative ease with which the participant is able to mentally process words in that concept category. Quicker reactions mean that a concept is more mentally accessible, and thus, &#34;on someone&#39;s mind&#34;24,29,30. As a consequence, lexical decision tasks make useful dependent variables, and can also be used as effective manipulation checks to measure if a recently primed concept (see reference30 for more information on priming) is indeed subsequently more cognitively accessible than it would be in the absence of a prime. Although the lexical decision task is a task that has been used in social psychology for decades29, the current manuscript presents some minor variations to the procedure, a link to an editable program template27, and an empirically validated list of words from the authors&#39; previous work that measures the cognitive accessibility of healthy versus non healthy foods20. It is the authors&#39; hope that the further adaptation of these two procedures will help lead to innovations in the fields of social psychological research, in eating behavior and energy regulation research, and will facilitate further comparative research that combines the perspectives and methodology of&#160;multiple disciplines.

<table border="0" cellpadding="0" cellspacing="0" width="607">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Survey Building Software</td>
			<td style="width:105px;">Qualtrics</td>
			<td style="width:119px;">Qualtrics Research Suite</td>
			<td style="width:167px;">Alternative survey building softwares / applications include Survey Monkey, Google Forms, Media Lab, and Inquisit software.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Behavioral Task Software (for lexical decision task)</td>
			<td style="width:105px;">Inquisit</td>
			<td style="width:119px;">Inquisit 4 Lab (4.0.8.0)</td>
			<td>Alternative behavioral task softwares / applications include Media Lab / Direct RT or programming the task into an internet browser using a programming language of your choice (such as java).</td>
		</tr>
		<tr height="106">
			<td height="106" style="height:106px;width:216px;">Batch File&#160;</td>
			<td style="width:105px;">Microsoft&#160;</td>
			<td style="width:119px;">Microsoft Notepad; Windows</td>
			<td></td>
		</tr>
		<tr height="106">
			<td height="106" style="height:106px;width:216px;">Lexical Decision Task Template</td>
			<td style="width:105px;">Millisecond</td>
			<td style="width:119px;">Millisecond survey library, cited template author is linked on page</td>
			<td>Can build a lexical decision task by hand in other behavioral task softwares.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Participant Scheduling and Compensation Software</td>
			<td style="width:105px;">SONA systems</td>
			<td style="width:119px;">SONA systems scheduling software</td>
			<td>Appointments can be arranged manually, too.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Statistical Analysis Software</td>
			<td style="width:105px;">IBM</td>
			<td style="width:119px;">IBM SPSS Statistics Standard, 22</td>
			<td>Alternate softwares include SAS and R.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Blood glucose manipulating beverege paradigm</td>
			<td style="width:105px;">Coca Cola&#160;</td>
			<td style="width:119px;">Sprite, Sprite Zero, Sparkling water</td>
			<td>Can use any store brand sugary beverage, non calorically sweetened beverage, and sparkling water beverage, as long as beverages are not easily discernable from each other by sight.&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Lancet</td>
			<td style="width:105px;">Assure</td>
			<td style="width:119px;">Assure Lanets 23 gauge</td>
			<td>Many brands of testing lancets available both online and at local pharmacies.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Blood glucose testing meter</td>
			<td style="width:105px;">Bayer&#39;s</td>
			<td style="width:119px;">Breeze 2</td>
			<td>Many brands of testing meters available both online and at local pharmacies.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Blood glucose testing strips</td>
			<td style="width:105px;">Bayer&#39;s</td>
			<td style="width:119px;">Breeze 2</td>
			<td>Many brands of testing strips available both online and at local pharmacies, but they must be compatible with your chosen meter.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">&#160;Nitrile exam gloves (400 count)</td>
			<td style="width:105px;">Kirkland</td>
			<td style="width:119px;">Kirkland Signature Nitrile Exam Gloves</td>
			<td>Any medical grade exam glove that provides sufficient protection from blood exposure can be used.</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Disinfecting wipes</td>
			<td style="width:105px;">Lysol</td>
			<td style="width:119px;">Lysol Disinfecting Wipes Lemon Scent</td>
			<td>Any wipe that can kill off any bloodborne or contact born contaminants.</td>
		</tr>
	</tbody>
</table>

a method for manipulating blood glucose and measuring resulting changes in cognitive accessibility of target stimuli

Much research in social psychology has investigated the impact of bodily energy need on cognition and decision-making. As such, blood glucose, the body's primary energy source, has been of special interest to researchers for years. Fluctuations in blood glucose have been linked to a variety of changes in cognitive and behavioral processes, such as self-control, political attitudes, and eating behavior. To help meet growing interest in the links between bodily energy need and these processes, this manuscript offers a simple methodology to experimentally manipulate blood glucose using a fasting procedure followed by administration of a sugar-sweetened, unsweetened, or artificially-sweetened beverage. This is followed by presentation of a method for measuring resulting changes in implicit cognition using a lexical decision-task. In this task, participants are asked to identify whether strings of letters are words or non-words and response latencies are recorded. Sample results from a recent publication are presented as an example of the applications for the experimental manipulation of blood glucose and the lexical decision task measures.

Participants
The above methods were implemented in a study run by Hill and colleagues20 at a midsize, private university in the southern United States. The undergraduate population at the university provided the subject sample and participants received partial course credit as compensation for study participation. Using the exact methods outlined in the current manuscript protocol, the authors ran participants through...

Watch this Scientific Journal Video about A Method for Manipulating Blood Glucose and Measuring Resulting Changes in Cognitive Accessibility of Target Stimuli at JoVE.com

A Method for Manipulating Blood Glucose and Measuring Resulting Changes in Cognitive Accessibility of Target Stimuli

The authors introduce a method for manipulating blood glucose and measuring resulting changes in cognitive accessibility of target words using a lexical decision task.

Much research in social psychology has investigated the impact of bodily energy need on cognition and decision-making.  As such, blood glucose, the body's ...

The overall goal of this methodology is to experimentally manipulate blood glucose using a fasting procedure followed by administration of a beverage. This is followed by the presentation of a method for measuring changes in implicit cognition using a lexical decision task. This method will show researchers how to experimentally manipulate participants'blood glucose levels and then program a task to measure changes in implicit cognition that results.The main advantage of this technique is that it's relatively inexpensive and easy to perform. Although this method can be used to measure the impact of energy need on changes in implicit cognition, it can also be used to measure the impact of energy need on other psychological processes and behavior. To begin, set up a two part survey using survey building software.In addition to the research task, make sure that the survey begins with a consent form and ends with a debriefing statement. Next, send out a recruitment email and select a pool of participants based on the inclusion and exclusion factors described in the accompanying text protocol. Ask them to refrain from eating or drinking any non water beverages for eight hours prior to their participation session.It is critical that you instruct participants to fast for a minimum of eight hours prior to the experimental session. Any participant that violates these instructions, needs to be excluded from data analysis. Before participants arrive in the laboratory, assign each participant a unique ID number and randomly assign them a beverage type using a participant log.Then, write each participant ID number being used in a session on an individual sticky note. Pre-pour the participant's chilled drink into an opaque disposable cup labeled with that participant's participant ID number. It's important that participants'ID numbers are correctly entered into the experimental log and their testing computer so that data can be linked at the end of the study.On the computer, open the study folder, double click on the Batch file icon, and select Run to open the survey. Bring participants into the lab and ask if they have met the pre-agreed fasting requirements. Have the participant digitally sign the consent form before starting the experiment.Following this, ask the participants a few short questions that will help to maintain the integrity of the cover story. When the computer screen indicates a stopping point, guide the participant to a sterile spot away from the survey to take a pre-manipulation blood glucose reading. Clean the participant's finger with a sterile wipe and then use a lancet to gently prick the side of the participant's index finger.Squeeze a small amount of blood onto a blood testing strip, and insert the strip into a glucometer. Write down the corresponding blood glucose reading and the time that the blood glucose reading was taken in the participant log. Then, wipe down the area with a sterilizing wipe to prepare it for the next participant.Offer the participant some hand sanitizer and a tissue to clean their finger. Also, provide the participant with a small adhesive bandage if they desire to use one to cover their finger. Following the glucose test, direct the participant to take a seat at the computer terminal.At this point, check that the cup matches the assigned condition and participant number recorded on the participant log and hand the participant the cup containing their assigned drink. Instruct the participant that the next task will involve making a series of consumer evaluations and that they should inform the experimenter when they reach the stop message at the end of the timed beverage consumption task. Next, instruct the participant that the task requires that they consume the entire beverage in two minutes or less and that the computer will time them.When the participant begins to drink the beverage, click the Next arrow on the survey page to begin the timed beverage consumption task. After the two minute period has elapsed, the survey will automatically continue to a message that prompts the participant to fill out the beverage evaluation questions. It will then automatically follow these questions with a filler task.While the participant completes the task, collect the used beverage cup from the participant's work space but do not throw it away. Mark down whether or not the participant finished their entire beverage in the experimental log next to the participant's ID number. The filler task will last for 10 minutes to allow the changes in blood glucose level to occur.Upon completion of the 10 minute filler task, a Stop message will appear. At this point the participant should submit and close the survey. Then, immediately take another blood glucose reading and proceed to the lexical decision task.To begin the lexical decision task, double click and open the software. Enter the participant's ID number into the prompt and initiate the programmed lexical decision task by clicking the Run button on the prompt window. At this point, briefly describe the lexical decision task to the participant and instruct them to notify the researcher when the task is finished.Then, allow the participant time to complete the lexical decision task on the computer. After finishing the task, close the lexical decision task out fully by hitting the space bar. Next, ensure that the batch file opens the final survey portion, which contains the socio-demographic questions and a debriefing statement as described in the accompanying text protocol.At the conclusion of the entire study, debrief, compensate, and dismiss the participant. After the participant leaves, flag the data of any participant that did not meet fasting requirements, whose fasting blood glucose read higher than 100 milligrams per deciliter, or that did not finish their drink. Results of a study based on this methodology revealed that participants who drank non calorically sweetened beverages responded more quickly to high calorie words than participants who drank sugar sweetened or unsweetened beverages.Results also revealed no differences in mean reaction time to these same high calorie words between participants who drank sugar sweetened or unsweetened beverages. In addition, there were no effects of drink type on participants'reaction times to low calorie food words or non words. After watching this video, you should have a good idea of how to experimentally manipulate participants'blood glucose levels and then measure resulting changes in implicit cognition.These procedures can be used either together or separately and can be done in under one hour if performed properly. Don't forget that working with human blood, even in small amounts, can be extremely hazardous. Always take proper precautions such as wearing rubber gloves and using appropriate sanitation techniques when performing this procedure.

a-method-for-manipulating-blood-glucose-measuring-resulting-changes

Research

JoVE Journal

Behavior

The Crossmodal Congruency Task as a Means to Obtain an Objective Behavioral Measure in the Rubber Hand Illusion Paradigm

The rubber hand illusion (RHI) is a popular experimental paradigm. Participants view touch on an artificial rubber hand while the participants' own hidden hand is touched. If the viewed and felt touches are given at the same time then this is sufficient to induce the compelling experience that the rubber hand is one's own hand. The RHI can be used to investigate exactly how the brain constructs distinct body representations for one's own body. Such representations are crucial for successful interactions with the external world. To obtain a subjective measure of the RHI, researchers typically ask participants to rate statements such as "I felt as if the rubber hand were my hand". Here we demonstrate how the crossmodal congruency task can be used to obtain an objective behavioral measure within this paradigm.
The variant of the crossmodal congruency task we employ involves the presentation of tactile targets and visual distractors. Targets and distractors are spatially congruent (i.e. same finger) on some trials and incongruent (i.e. different finger) on others. The difference in performance between incongruent and congruent trials - the crossmodal congruency effect (CCE) - indexes multisensory interactions. Importantly, the CCE is modulated both by viewing a hand as well as the synchrony of viewed and felt touch which are both crucial factors for the RHI.
The use of the crossmodal congruency task within the RHI paradigm has several advantages. It is a simple behavioral measure which can be repeated many times and which can be obtained during the illusion while participants view the artificial hand. Furthermore, this measure is not susceptible to observer and experimenter biases. The combination of the RHI paradigm with the crossmodal congruency task allows in particular for the investigation of multisensory processes which are critical for modulations of body representations as in the RHI.

We demonstrate how an objective measure can be employed in the widely employed rubber hand illusion paradigm. This measure is obtained by modifying the well-established crossmodal congruency task. This task allows the investigation of multisensory processes which are critical for modulations of body representations as in the rubber hand illusion.

The rubber hand illusion (RHI) is a popular experimental paradigm. Participants view touch on an artificial rubber hand while the participants' own hidden ...

Assessment of Age-related Changes in Cognitive Functions Using EmoCogMeter, a Novel Tablet-computer Based Approach

The main goal of this study was to assess the usability of a tablet-computer-based application (EmoCogMeter) in investigating the effects of age on cognitive functions across the lifespan in a sample of 378 healthy subjects (age range 18-89 years). Consistent with previous findings we found an age-related cognitive decline across a wide range of neuropsychological domains (memory, attention, executive functions), thereby proving the usability of our tablet-based application. Regardless of prior computer experience, subjects of all age groups were able to perform the tasks without instruction or feedback from an experimenter. Increased motivation and compliance proved to be beneficial for task performance, thereby potentially increasing the validity of the results. Our promising findings underline the great clinical and practical potential of a tablet-based application for detection and monitoring of cognitive dysfunction.

We tested the usability of a tablet-computer-based application (EmoCogMeter) in investigating the effects of age on cognition. Results show an age-related cognitive decline, thereby proving the usability of our application. Findings underline the great clinical and practical potential of a tablet-based application for detection and monitoring of cognitive dysfunction.

The main goal of this study was to assess the usability of a tablet-computer-based application (EmoCogMeter) in investigating the effects of age on ...

A Method for Investigating Age-related Differences in the Functional Connectivity of Cognitive Control Networks Associated with Dimensional Change Card Sort Performance

The ability to adjust behavior to sudden changes in the environment develops gradually in childhood and adolescence. For example, in the Dimensional Change Card Sort task, participants switch from sorting cards one way, such as shape, to sorting them a different way, such as color. Adjusting behavior in this way exacts a small performance cost, or switch cost, such that responses are typically slower and more error-prone on switch trials in which the sorting rule changes as compared to repeat trials in which the sorting rule remains the same. The ability to flexibly adjust behavior is often said to develop gradually, in part because behavioral costs such as switch costs typically decrease with increasing age. Why aspects of higher-order cognition, such as behavioral flexibility, develop so gradually remains an open question. One hypothesis is that these changes occur in association with functional changes in broad-scale cognitive control networks. On this view, complex mental operations, such as switching, involve rapid interactions between several distributed brain regions, including those that update and maintain task rules, re-orient attention, and select behaviors. With development, functional connections between these regions strengthen, leading to faster and more efficient switching operations. The current video describes a method of testing this hypothesis through the collection and multivariate analysis of fMRI data from participants of different ages.

This video presents a method of examining age-related changes in functional connectivity of cognitive control networks engaged by targeted tasks/processes. The technique is based on multi-variate analysis of fMRI data.

The ability to adjust behavior to sudden changes in the environment develops gradually in childhood and adolescence. For example, in the Dimensional ...

Irrelevant Stimuli and Action Control: Analyzing the Influence of Ignored Stimuli via the Distractor-Response Binding Paradigm

Selection tasks in which simple stimuli (e.g. letters) are presented and a target stimulus has to be selected against one or more distractor stimuli are frequently used in the research on human action control. One important question in these settings is how distractor stimuli, competing with the target stimulus for a response, influence actions. The distractor-response binding paradigm can be used to investigate this influence. It is particular useful to separately analyze response retrieval and distractor inhibition effects. Computer-based experiments are used to collect the data (reaction times and error rates). In a number of sequentially presented pairs of stimulus arrays (prime-probe design), participants respond to targets while ignoring distractor stimuli. Importantly, the factors response relation in the arrays of each pair (repetition vs. change) and distractor relation (repetition vs. change) are varied orthogonally. The repetition of the same distractor then has a different effect depending on response relation (repetition vs. change) between arrays. This result pattern can be explained by response retrieval due to distractor repetition. In addition, distractor inhibition effects are indicated by a general advantage due to distractor repetition. The described paradigm has proven useful to determine relevant parameters for response retrieval effects on human action.

The distractor-response binding paradigm is described. It can be used to shed light on the influence irrelevant stimuli, competing with targets for a response, can have on human action. Both response retrieval effects and distractor inhibition effects can be analyzed within the paradigm.

Selection tasks in which simple stimuli (e.g. letters) are presented and a target stimulus has to be selected against one or more distractor stimuli are ...

A Cognitive Paradigm to Investigate Interference in Working Memory by Distractions and Interruptions

Goal-directed behavior is often impaired by interference from the external environment, either in the form of distraction by irrelevant information that one attempts to ignore, or by interrupting information that demands attention as part of another (secondary) task goal. Both forms of external interference have been shown to detrimentally impact the ability to maintain information in working memory (WM). Emerging evidence suggests that these different types of external interference exert different effects on behavior and may be mediated by distinct neural mechanisms. Better characterizing the distinct neuro-behavioral impact of irrelevant distractions versus attended interruptions is essential for advancing an understanding of top-down attention, resolution of external interference, and how these abilities become degraded in healthy aging and in neuropsychiatric conditions. This manuscript describes a novel cognitive paradigm developed the Gazzaley lab that has now been modified into several distinct versions used to elucidate behavioral and neural correlates of interference, by to-be-ignored distractors versus to-be-attended interruptors. Details are provided on variants of this paradigm for investigating interference in visual and auditory modalities, at multiple levels of stimulus complexity, and with experimental timing optimized for electroencephalography (EEG) or functional magnetic resonance imaging (fMRI) studies. In addition, data from younger and older adult participants obtained using this paradigm is reviewed and discussed in the context of its relationship with the broader literatures on external interference and age-related neuro-behavioral changes in resolving interference in working memory.

A novel cognitive paradigm is developed to elucidate behavioral and neural correlates of interference by to-be-ignored distractors versus interference by to-be-attended interruptors during a working memory task. In this manuscript, several variants of this paradigm are detailed, and data obtained with this paradigm in younger/older adult participants is reviewed.

Goal-directed behavior is often impaired by interference from the external environment, either in the form of distraction by irrelevant information that ...

The Modified Hole Board - Measuring Behavior, Cognition and Social Interaction in Mice and Rats

This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure multiple dimensions of unconditioned behavior in small laboratory mammals (e.g., mice, rats, tree shrews and small primates). This paradigm is a valuable alternative for the use of a behavioral test battery, since a broad behavioral spectrum of an animal&#8217;s behavioral profile can be investigated in one single test.
The apparatus consists of a box, representing the &#8216;protected&#8217; area, separated from a group compartment. A board, on which small cylinders are staggered in three lines, is placed in the center of the box, representing the &#8216;unprotected&#8217; area of the set-up. The cognitive abilities of the animals can be measured by baiting some cylinders on the board and measuring the working and reference memory. Other unconditioned behavior, such as activity-related-, anxiety-related- and social behavior, can be observed using this paradigm. Behavioral flexibility and the ability to habituate to a novel environment can additionally be observed by subjecting the animals to multiple trials in the mHB, revealing insight into the animals&#8217; adaptive capacities.
Due to testing order effects in a behavioral test battery, na&#239;ve animals should be used for each individual experiment. By testing multiple behavioral dimensions in a single paradigm and thereby circumventing this issue, the number of experimental animals used is reduced. Furthermore, by avoiding social isolation during testing and without the need to food deprive the animals, the mHB represents a behavioral test system, inducing if any, very low amount of stress.

This protocol describes the modified hole board, which is a behavioral test set-up that comprises the characteristics of an open field and a traditional hole board. This set-up enables the differential analysis of unconditioned behavior of small laboratory mammals as well as the analysis of cognitive abilities.

This protocol describes the modified hole board (mHB), which combines features from a traditional hole board and open field and is designed to measure ...

Event-related Potentials During Target-response Tasks to Study Cognitive Processes of Upper Limb Use in Children with Unilateral Cerebral Palsy

Unilateral Cerebral Palsy (CP) is a neurodevelopmental disorder that is a very common cause of disability in childhood. It is characterized by unilateral motor impairments that are frequently dominated in the upper limb. In addition to a reduced movement capacity of the affected upper limb, several children with unilateral CP show a reduced awareness of the remaining movement capacity of that limb. This phenomenon of disregarding the preserved capacity of the affected upper limb is regularly referred to as Developmental Disregard (DD). Different theories have been postulated to explain DD, each suggesting slightly different guidelines for therapy. Still, cognitive processes that might additionally contribute to DD in children with unilateral CP have never been directly studied. The current protocol was developed to study cognitive aspects involved in upper limb control in children with unilateral CP with and without DD. This was done by recording event-related potentials (ERPs) extracted from the ongoing EEG during target-response tasks asking for a hand-movement response. ERPs consist of several components, each of them associated with a well-defined cognitive process (e.g., the N1 with early attention processes, the N2 with cognitive control and the P3 with cognitive load and mental effort). Due to its excellent temporal resolution, the ERP technique enables to study several covert cognitive processes preceding overt motor responses and thus allows insight into the cognitive processes that might contribute to the phenomenon of DD. Using this protocol adds a new level of explanation to existing behavioral studies and opens new avenues to the broader implementation of research on cognitive aspects of developmental movement restrictions in children.

Several children with unilateral Cerebral Palsy seem to disregard the preserved capacity of their affected upper limb. This Developmental Disregard is extensively described in the literature but the involved cognitive processes have not been studied. To study underlying cognitive factors of upper limb control, an event-related potential protocol was developed.

Unilateral Cerebral Palsy (CP) is a neurodevelopmental disorder that is a very common cause of disability in childhood. It is characterized by unilateral ...

A Pressure Injection System for Investigating the Neuropharmacology of Information Processing in Awake Behaving Macaque Monkey Cortex

The top-down modulation of feed-forward cortical information processing is functionally important for many cognitive processes, including the modulation of sensory information processing by attention. However, little is known about which neurotransmitter systems are involved in such modulations. A practical way to address this question is to combine single-cell recording with local and temporary neuropharmacological manipulation in a suitable animal model. Here we demonstrate a technique combining acute single-cell recordings with the injection of neuropharmacological agents in the direct vicinity of the recording electrode. The video shows the preparation of the pressure injection/recording system, including preparation of the substance to be injected. We show a rhesus monkey performing a visual attention task and the procedure of single-unit recording with block-wise pharmacological manipulations.

Here, we show the pressure injection of neuropharmacological substances during single-cell recording in an awake, behaving macaque monkey. This procedure allows pharmacological manipulation in the direct vicinity of a cortical recording site.

The top-down modulation of feed-forward cortical information processing is functionally important for many cognitive processes, including the modulation ...

Introducing Clicker Training as a Cognitive Enrichment for Laboratory Mice

Establishing new refinement strategies in laboratory animal science is a central goal in fulfilling the requirements of Directive 2010/63/EU. Previous research determined a profound impact of gentle handling protocols on the well-being of laboratory mice. By introducing clicker training to the keeping of mice, not only do we promote the amicable treatment of mice, but we also enable them to experience cognitive enrichment. Clicker training is a form of positive reinforcement training using a conditioned secondary reinforcer, the "click" sound of a clicker, which serves as a time bridge between the strengthened behavior and an upcoming reward. The effective implementation of the clicker training protocol with a cohort of 12 BALB/c inbred mice of each sex proved to be uncomplicated. The mice learned rather quickly when challenged with tasks of the clicker training protocol, and almost all trained mice overcame the challenges they were given (100% of female mice and 83% of male mice). This study has identified that clicker training for mice strongly correlates with reduced fear in the mice during human-mice interactions, as shown by reduced anxiety-related behaviors (e.g., defecation, vocalization, and urination) and fewer depression-like behaviors (e.g., floating). By developing a reliable protocol that can be easily integrated into the daily routine of the keeping of laboratory mice, the lifetime experience of welfare in the mice can be improved substantially.

The development of new refinement strategies for laboratory mice is a challenging task that contributes towards fulfilling the 3R principle. This protocol introduces clicker training as a cognitive enrichment program for laboratory mice.

Establishing new refinement strategies in laboratory animal science is a central goal in fulfilling the requirements of Directive 2010/63/EU. Previous ...

An Automated Method to Determine the Performance of Drosophila in Response to Temperature Changes in Space and Time

Temperature is a ubiquitous environmental factor that affects how species distribute and behave. Different species of Drosophila fruit flies have specific responses to changing temperatures according to their physiological tolerance and adaptability. Drosophila flies also possess a temperature sensing system that has become fundamental to understanding the neural basis of temperature processing in ectotherms. We present here a temperature-controlled arena that permits fast and precise temperature changes with temporal and spatial control to explore the response of individual flies to changing temperatures. Individual flies are placed in the arena and exposed to pre-programmed temperature challenges, such as uniform gradual increases in temperature to determine reaction norms or spatially distributed temperatures at the same time to determine preferences. Individuals are automatically tracked, allowing the quantification of speed or location preference. This method can be used to rapidly quantify the response over a large range of temperatures to determine temperature performance curves in Drosophila or other insects of similar size. In addition, it can be used for genetic studies to quantify temperature preferences and reactions of mutants or wild-type flies. This method can help uncover the basis of thermal speciation and adaptation, as well as the neural mechanisms behind temperature processing.

An Automated Method to Determine the Performance of Drosophila in Response to Temperature Changes in Space and Time

Here we present a protocol to automatically determine the locomotor performance of Drosophila at changing temperatures using a programmable temperature-controlled arena that produces fast and accurate temperature changes in time and space.

Temperature is a ubiquitous environmental factor that affects how species distribute and behave. Different species of Drosophila fruit flies have specific ...