This study was funded in part through the Faculty Research Grant Program (FRGP) sponsored through the School of Public Health at Indiana University, Bloomington, IN. The authors would like to thank Dr. Alison Voight and Melissa Page for their editorial assistance and constructive comments.

This study follows the policies and guidelines of Human Research Protection Program of Indiana University Institutional Review Board.
1. Location selection
<ol>
	<li>Select the number of sites (n) based on different levels of nature. 
	NOTE: We chose three sites for our work. Using a continuum based on levels of &#34;naturalness&#34;, Site A was considered the most natural and is comprised of approximately 1,200 acres of wooded ridges bordering a lake and set within a deciduous forest. The most common activities include walking and wildlife watching. Site B was a 33-acre municipal park featuring walking paths, places for gatherings, playgrounds, and open field space for causal recreational activities. Site C was an urban, indoor exercise facility with the lowest level of naturalness. All three sites are in relatively close proximity to a medium-size city (estimated population of 46,000 people) in the midwestern United States.</li>
</ol>
2. Participant screening and preparation
<ol>
	<li>Complete participant recruitment before subjects engage in recreational experiences. 
	NOTE: For Sites A and B, subjects were approached by the researcher in the parking lot of the park entrance. For Site C, subjects were approached at the front desk of the indoor exercise facility. To control for differences in activity type, subjects recruited for both Sites A and B were predominately hiking, while for Site C the primary activity was running or walking on the indoor track.</li>
	<li>During recruitment, remind subjects to comply with the guidelines related to collecting salivary cortisol samples. They must not eat or drink 10 min before providing saliva samples. 
	NOTE: It should be noted that in this case, the saliva samples were not normalized for volume or dilution (concentration) -&#160;i.e. whether the participants were adequately hydrated and/or did hydration change between the sample collections.</li>
	<li>Give red armbands (or equivalently noticeable clothing) to each participant to allow for easy identification when emerging at the end of their engagements.</li>
	<li>Assign a 30-40 min time allotment so that all subjects across the three sites spend a similar amount of time in each site. Exclude subjects who spend substantially more or less time than the rest of the sample.</li>
	<li>Keep the type of activity engaged consistent. 
	NOTE: In this case, the &#34;medium&#34;&#160;activity was walking or hiking. Subjects who engaged in activities substantially different from walking or hiking were excluded from the sample. For example, subjects who were fishing, picnicking, or weight lifting were not included in the respective samples.</li>
</ol>
3. Conditions and experimental design
<ol>
	<li>Use a quasi-experimental pre-test/post-test design.</li>
	<li>After identifying subjects and upon their agreeing to participate, ask each subject to read and sign an IRB form explaining the voluntary nature, purpose, and procedures of the study.</li>
	<li>Following this process, give subjects a piece of clothing (e.g., red armband) for future identification and obtain physiological and psychological measures of stress levels (i.e., PSQ, 1-2 mL of saliva that is spit or drooled into a test tube). Collect samples from the late afternoon to early evening. 
	NOTE: These data were collected by researchers both 1) just before subjects entered the site and 2) immediately upon ending visitation to the site.</li>
</ol>
4. Saliva samples
<ol>
	<li>To avoid sample dilution, ask subjects not to eat, drink, or rinse mouths 10 min before providing saliva samples.</li>
	<li>Ask subjects to provide 1-2 mL saliva samples (excluding foam) just prior to the recreational experience and immediately following conclusion of the experience.</li>
	<li>Collect saliva samples using a passive drool method:
	<ol>
		<li>Provide subjects with a 2 in plastic drinking straw to drool into a 2 mL cryovial (see Table of Materials).</li>
		<li>Instruct subjects to allow saliva to pool in their mouths, then drool down the straw and into the cryovial. According to the Saliva Collection and Handling Advice (2011), 1 mL (excluding foam) is adequate for most tests.</li>
		<li>Label samples with an assigned 3-digit ID number (i.e., 001) and letter to indicate the timing of data collection (i.e., A represents pre-test, B represents post-test; where 001A represents the saliva sample provided by participant 001 before conducting the recreational experience).</li>
		<li>After the sample is collected and labeled, it should then be stored frozen temporarily in a steroid foam box full of dry ice for no more than 2 h.</li>
		<li>Transport the marked samples to a laboratory and store at -80 &#176;C until analyzed.</li>
	</ol>
	</li>
</ol>
5. Quantification of &#945;-amylase
NOTE: In this assay, &#945;-amylase hydrolyzes 2-chloro-p-nitrophenyl-&#945;-D-maltotrioside to 2-chloro-nitrophenol and forms glucose, 2-chloro-p-nitrophenyl-&#945;-D-maltoside, maltotriose, and glucose. The reaction is monitored at an absorbance of 405 nm, which corresponds to &#945;-amylase activity in the sample. This assay demonstrates linearity between 0 and 2000 U/L.
<ol>
	<li>Materials
	<ol>
		<li>Used a liquid amylase reagent set (see Table of Materials) to quantify &#945;-amylase in saliva samples. All reagents are provided as ready-to-use liquids and stored at 0-4 &#176;C.</li>
		<li>Use a multi-mode reader (see Table of Materials) capable of reading an optical density at 405 nm with a temperature controlled to 37 &#176;C during the assay.</li>
	</ol>
	</li>
	<li>Analysis
	<ol>
		<li>Thaw the samples on ice prior to analysis.</li>
		<li>Dilute samples 1:10 with 1x PBS (10 &#181;L of saliva + 90 &#181;L of PBS).</li>
		<li>Analyze each sample in duplicate.</li>
		<li>Equilibrate the amylase reagent to 20-25 &#176;C for at least 30 min.</li>
		<li>Add 0.1 mL of amylase reagent to a 96 well microplate for each sample.</li>
		<li>Pre-incubate the microplate at 37 &#176;C for a minimum of 5 min.</li>
		<li>Add 2.5 &#181;L of the sample to the amylase reagent.</li>
		<li>Take an initial reading after 60 s.</li>
		<li>Continue readings every 60 s for an additional 2 min.</li>
		<li>Calculate the mean absorbance difference per minute (&#916;Abs/min).</li>
	</ol>
	</li>
	<li>Calculation
	<ol>
		<li>To calculate amylase activity, use the following formula: 
		<img alt="Equation 1" src="/files/ftp_upload/59272/59272eq1.jpg" /> 
		Where &#916;Abs/min = changes in absorbance difference per minute; TV = total assay volume (0.1025 mL); *1000 = conversion of U/mL to U/L; MMA = millimolar absorptivity of 2-chloro-p-nitrophenol = 12.9; SV = sample volume (0.0025 mL); and LP = light path (1 cm). Substituting gives: 
		<img alt="Equation 2" src="/files/ftp_upload/59272/59272eq2.jpg" /> 
		Therefore, multiply the &#916;Abs/min by 3178x the dilution factor (10) to obtain amylase in U/L.</li>
		<li>For samples above 2000 U/L (assay linearity) dilute further (at least 2x using PBS) and re-assay, then multiply the &#945;-amylase result by the additional dilution factor.</li>
	</ol>
	</li>
</ol>
6. Quantification of cortisol
NOTE: In this assay, free cortisol is quantified in saliva using a cortisol standard curve. Standards and diluted samples are added to a microtiter plate that is pre-coated with an antibody. A cortisol-peroxidase conjugate is added to the wells, followed by addition of a monoclonal antibody to cortisol. The amount of cortisol/peroxidase conjugate binding decreases as the concentration of cortisol in the sample increases.
<ol>
	<li>Materials
	<ol>
		<li>Use a Cortisol Enzyme Immunoassay Kit (see Table of Materials) to quantify cortisol in saliva samples. All reagents needed to perform this assay are included in the kit. All components of the kit are stored at 0-4 &#176;C prior to reaching the expiration date.</li>
		<li>Use a spectrophotometer able to read an optical density (OD) at 450 nm (see Table of Materials), as well as software capable of using OD recordings from the plate reader to perform four-parameter logistic curve (4 PLC) fitting.</li>
	</ol>
	</li>
	<li>Reagent preparation
	<ol>
		<li>Allow all reagents to equilibrate to 20-25 &#176;C for a minimum of 30 min.</li>
		<li>Dilute the cortisol assay buffer 1:5 using deionized water.</li>
		<li>Dilute the wash buffer 1:20 using deionized water. 
		NOTE: Assay and wash buffers are stable for 3 months when stored at 0-4 &#176;C.</li>
	</ol>
	</li>
	<li>Sample preparation
	<ol>
		<li>Thaw the samples on ice prior to analysis.</li>
		<li>Dilute samples 1:10 with cortisol assay buffer (20 &#181;L of saliva + 180 &#181;L of buffer) and use within 2 h of preparation.</li>
	</ol>
	</li>
	<li>Preparation of standards
	<ol>
		<li>Label glass test tubes #1-#7.</li>
		<li>Pipet 225 &#956;L of assay buffer into tube #1 and 125 &#956;L of buffer into tubes #2-#7.</li>
		<li>Add 25 &#956;L of the cortisol stock solution to tube #1 and vortex.</li>
		<li>Remove 125 &#956;L of buffer from tube #1 and add it to tube #2, then vortex.</li>
		<li>Repeat the serial dilutions for tubes #3-#7. 
		NOTE: The final cortisol concentrations of each standard is shown in Table 1.</li>
		<li>Standards must be used within 2 h of preparation.</li>
	</ol>
	</li>
</ol>
<table fo:keep-together.within-page="1">
	<tbody>
		<tr>
			<td>Standard</td>
			<td>#1</td>
			<td>#2</td>
			<td>#3</td>
			<td>#4</td>
			<td>#5</td>
			<td>#6</td>
			<td>#7</td>
		</tr>
		<tr>
			<td>Assay Buffer Volume (&#956;L)</td>
			<td>225</td>
			<td>125</td>
			<td>125</td>
			<td>125</td>
			<td>125</td>
			<td>125</td>
			<td>125</td>
		</tr>
		<tr>
			<td>Addition</td>
			<td>Stock Std</td>
			<td>#1</td>
			<td>#2</td>
			<td>#3</td>
			<td>#4</td>
			<td>#5</td>
			<td>#6</td>
		</tr>
		<tr>
			<td>Volume of Addition (&#181;L)</td>
			<td>25</td>
			<td>125</td>
			<td>125</td>
			<td>125</td>
			<td>125</td>
			<td>125</td>
			<td>125</td>
		</tr>
		<tr>
			<td>Final Concentration (pg/mL)</td>
			<td>3200</td>
			<td>1600</td>
			<td>800</td>
			<td>400</td>
			<td>200</td>
			<td>100</td>
			<td>50</td>
		</tr>
	</tbody>
</table>
Table 1: Standard curve preparation table.
<ol start="5">
	<li>Analysis
	<ol>
		<li>Use the plate layout below in Figure 1 as a guide to set up the microplate.</li>
		<li>It is recommended to use a multichannel pipette for addition of reagents.</li>
		<li>Add 50 &#956;L of samples or standards into the appropriate number of wells in the plate. Samples and standards should be run in duplicate.</li>
		<li>Add assay buffer (75 &#956;L) into the non-specific binding (NSB) wells.</li>
		<li>Add assay buffer (50 &#956;L) into the maximum binding (B0) wells and zero standard (blank) wells.</li>
		<li>Add 25 &#956;L of the cortisol conjugate to each well.</li>
		<li>Add 25 &#956;L of the cortisol antibody to each well, except for the NSB wells.</li>
		<li>Gently tap the side of the plate to mix the reagents.</li>
		<li>Cover with the plate sealer and shake at room temperature (RT) at 20-25 &#176;C for 1 h.</li>
		<li>Remove the well contents and rinse each well 4x with wash buffer (300 &#924;l). Tap the plate to dry on absorbent towels between washes.</li>
		<li>Add the TMB substrate to each well (100 &#956;L).</li>
		<li>Incubate the plate at 20-25 &#176;C for 30 min without shaking.</li>
		<li>Add stop solution to each well (50 &#956;L).</li>
		<li>Read the optical density in each well of the microplate at 450 nm.</li>
		<li>Average the optical densities for each standard, then sample and subtract the mean optical density for the NSB wells.</li>
		<li>Calculate the % bound (B/B0) for all samples using maximum binding (B0) controls.</li>
		<li>Create a standard curve using software capable of four-parameter logistic regression curve fitting, calculated from the %B/B0 curve.</li>
		<li>Multiply the result by the dilution factor (10) to obtain cortisol values in pg/mL.</li>
		<li>Samples with optical densities falling above the highest standard should be further diluted with assay buffer and re-assayed, then the result should be multiplied by the additional dilution factor.</li>
	</ol>
	</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/59272/59272fig1.jpg" /> 
Figure 1: Example plate layout. <a href="https://www.jove.com/files/ftp_upload/59272/59272fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
7. Psychological measurement (Perceived Stress Questionnaire)
<ol>
	<li>Measure psychological levels of subjects using the PSQ published by Fliege et al.13, which includes four factors (worry, tension, tension, joy) and utilizes 20 items.</li>
	<li>Ask the subject to fill out the PSQ just prior to their recreational experience and immediately following conclusion of the experience.</li>
	<li>Tag questionnaires with a 3-digit ID number identical to each subject&#39;s biophysiological level of stress.</li>
</ol>

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The authors declare no conflicts of interest.

The aim of this study is to identify potential changes in stress using biophysical and psychological instruments following recreational visitation to three different settings with different levels of nature. Both cortisol and &#945;-amylase have been shown to be reliable indicators of levels of psychological stress. The amylase assay procedure described in this study has been adapted to a 96 well format. When amylase levels in saliva are high, absorbance changes occur rapidly. Therefore, it is critical to limit the numbe...

Elevated stress levels have long been linked to many serious health conditions such as heart disease, obesity, and psychological disorders1,2,3. A growing body of research suggests that close proximity or visitation to natural settings such as park and non-developed landscapes can have a remarkable effect on psychological well-being and decreased levels of stress1,4,5,6,7,8,9,10. Explanations for the effects of natural settings and stress levels have included the following: (1) natural settings provide venues for physical activity8,11 and (2) visitors to natural environments have the ability to focus on more non-task thought processes, thereby leading to a reduction in attention fatigue12. To determine the effects of nature on stress reduction, this study utilizes a self-report of psychological stress (PSQ) and two saliva-based biomarkers, cortisol and &#945;-amylase, after visitation to three different recreation sites. These locations vary among their levels of &#34;naturalness&#34;&#160;and include a wilderness-type setting, municipal park, and local fitness and recreation facility.
This study aims to address the following research questions: (RQ1) Are there differences in levels of biophysical stress measured by salivary cortisol and &#945;-amylase when compared across all three sites (i.e., natural, semi-natural, built)? (RQ2) Are there differences in levels of psychological stress measured by the PSQ (manifested by four constructs: demands, worries, tension, and joy) when compared across all three sites (i.e., natural, semi-natural, built)?

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measuring biophysical and psychological stress levels following visitation to three locations with differing levels of nature

Visitation to natural environments has been linked to psychological stress reduction. Although most stress-related research has relied on self-report formats, a growing number of studies now incorporate biological stress-related hormones and catalysts, such as cortisol and &#945;-amylase, to measure levels of stress. Presented here is a protocol to examine the effects on levels of biophysical and psychological stress following visitation to three different locations with differing levels of nature. Biophysical and self-reported psychological stress levels are measured immediately upon entering the selected locations and just prior to the visitors leaving the site. Using a &#34;drool&#34;&#160;method, the biophysical measure consists of 1-2 mL samples of saliva provided by study subjects upon entry to one of three study locations. As prescribed by extant literature, the saliva is collected within a 45 minute time frame following the end of the visitor&#8217;s engagement at the location. Following saliva collection, the samples are labeled and transported to a biological lab. Cortisol is the biophysical variable of interest in this study and measured using an ELISA process with a TECAN plate reader. To measure self-reported stress, the Perceived Stress Questionnaire (PSQ), which reports levels of worry, tension, joy, and perceived demands. Data are collected at all three sites in the late afternoon through early evening. When compared across all three settings, stress levels, as measured by both the biological markers and self-reports, are significantly lower after visitation to the most natural setting.

Sample Description 
Utilizing a quota sampling technique, this study recruited 35 visitors from each of the three sites. In total, 105 subjects were recruited in this study, including 63 males and 42 females. Average ages of visitors recruited from three different sites were 25.9 years (Site A), 37.2 years (Site B), and 28.8 years (Site C). Frequencies of subjects&#39;&#160;visitation to the selected three sites were also recorded. For Site A and Site C, the majority of subjects visited this site on...

Watch this Scientific Journal Video about Measuring Biophysical and Psychological Stress Levels Following Visitation to Three Locations with Differing Levels of Nature at JoVE.com

Measuring Biophysical and Psychological Stress Levels Following Visitation to Three Locations with Differing Levels of Nature

The purpose of this paper is to identify changes in stress levels after visitation to three different settings and to describe the methods used in identifying stress levels based on measures of salivary cortisol, &#945;-amylase, and a psychological self-report instrument.&#160;

Visitation to natural environments has been linked to psychological stress reduction. Although most stress-related research has relied on self-report ...

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8.4K Views.  Illinois State University. The purpose of this paper is to identify changes in stress levels after visitation to three different settings and to describe the methods used in identifying stress levels based on measures of salivary cortisol, α-amylase, and a psychological self-report instrument. 

Video: Measuring Biophysical and Psychological Stress Levels Following Visitation to Three Locations with Differing Levels of Nature

Measuring Sensitivity to Viewpoint Change with and without Stereoscopic Cues

The speed and accuracy of object recognition is compromised by a change in viewpoint; demonstrating that human observers are sensitive to this transformation. Here we discuss a novel method for simulating the appearance of an object that has undergone a rotation-in-depth, and include an exposition of the differences between perspective and orthographic projections. Next we describe a method by which human sensitivity to rotation-in-depth can be measured. Finally we discuss an apparatus for creating a vivid percept of a 3-dimensional rotation-in-depth; the Wheatstone Eight Mirror Stereoscope. By doing so, we reveal a means by which to evaluate the role of stereoscopic cues in the discrimination of viewpoint rotated shapes and objects.

We discuss a novel method forviewpoint-rotation of visual stimuli, and demonstrate using a mirror stereoscopethe three-dimensional percept of rotation-in-depth. The technique can be used to investigate the role of stereoscopic cues in encoding viewpoint-rotated figures.

The speed and accuracy of object recognition is compromised by a change in viewpoint; demonstrating that human observers are sensitive to this ...

Uncovering Beat Deafness: Detecting Rhythm Disorders with Synchronized Finger Tapping and Perceptual Timing Tasks

A set of behavioral tasks for assessing perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) is presented here with the goal of uncovering rhythm disorders, such as beat deafness. Beat deafness is characterized by poor performance in perceiving durations in auditory rhythmic patterns or poor synchronization of movement with auditory rhythms (e.g., with musical beats). These tasks include the synchronization of finger tapping to the beat of simple and complex auditory stimuli and the detection of rhythmic irregularities (anisochrony detection task) embedded in the same stimuli. These tests, which are easy to administer, include an assessment of both perceptual and sensorimotor timing abilities under different conditions (e.g., beat rates and types of auditory material) and are based on the same auditory stimuli, ranging from a simple metronome to a complex musical excerpt. The analysis of synchronized tapping data is performed with circular statistics, which provide reliable measures of synchronization accuracy (e.g., the difference between the timing of the taps and the timing of the pacing stimuli) and consistency. Circular statistics on tapping data are particularly well-suited for detecting individual differences in the general population. Synchronized tapping and anisochrony detection are sensitive measures for identifying profiles of rhythm disorders and have been used with success to uncover cases of poor synchronization with spared perceptual timing. This systematic assessment of perceptual and sensorimotor timing can be extended to populations of patients with brain damage, neurodegenerative diseases (e.g., Parkinson&#8217;s disease), and developmental disorders (e.g., Attention Deficit Hyperactivity Disorder).

Behavioral tasks that allow for the assessment of perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) are presented. Synchronization of finger tapping to the beat of an auditory stimuli and detecting rhythmic irregularities provides a means of uncovering rhythm disorders.

A set of behavioral tasks for assessing perceptual and sensorimotor timing abilities in the general population (i.e., non-musicians) is presented here ...

Mindfulness in Motion (MIM): An Onsite Mindfulness Based Intervention (MBI) for Chronically High Stress Work Environments to Increase Resiliency and Work Engagement

A pragmatic mindfulness intervention to benefit personnel working in chronically high-stress environments, delivered onsite during the workday, is timely and valuable to employee and employer alike. Mindfulness in Motion (MIM) is a Mindfulness Based Intervention (MBI) offered as a modified, less time intensive method (compared to Mindfulness-Based Stress Reduction), delivered onsite, during work, and intends to enable busy working adults to experience the benefits of mindfulness. It teaches mindful awareness principles, rehearses mindfulness as a group, emphasizes the use of gentle yoga stretches, and utilizes relaxing music in the background of both the group sessions and individual mindfulness practice. MIM is delivered in a group format, for 1 hr/week/8 weeks. CDs and a DVD are provided to facilitate individual practice. The yoga movement is emphasized in the protocol to facilitate a quieting of the mind. The music is included for participants to associate the relaxed state experienced in the group session with their individual practice. To determine the intervention feasibility/efficacy we conducted a randomized wait-list control group in Intensive Care Units (ICUs). ICUs represent a high-stress work environment where personnel experience chronic exposure to catastrophic situations as they care for seriously injured/ill patients. Despite high levels of work-related stress, few interventions have been developed and delivered onsite for such environments. The intervention is delivered on site in the ICU, during work hours, with participants receiving time release to attend sessions. The intervention is well received with 97% retention rate. Work engagement and resiliency increase significantly in the intervention group, compared to the wait-list control group, while participant respiration rates decrease significantly pre-post in 6/8 of the weekly sessions. Participants value institutional support, relaxing music, and the instructor as pivotal to program success. This provides evidence that MIM is feasible, well accepted, and can be effectively implemented in a chronically high-stress work environment.

Mindfulness in Motion MIM: An Onsite Mindfulness Based Intervention MBI for Chronically High Stress Work Environments to Increase Resiliency and Work Engagement

The Mindfulness in Motion (MIM) protocol offers a pragmatic Mindfulness Based Intervention (MBI) on-site, for persons working in chronically high-stress work environments that significantly increases resiliency and work engagement. The protocol has proven feasible, beneficial, and is easily adaptable to other high-stress workplaces.

A pragmatic mindfulness intervention to benefit personnel working in chronically high-stress environments, delivered onsite during the workday, is timely ...

A Dual Task Procedure Combined with Rapid Serial Visual Presentation to Test Attentional Blink for Nontargets

When viewers search for targets in a rapid serial visual presentation (RSVP) stream, if two targets are presented within about 500 msec of each other, the first target may be easy to spot but the second is likely to be missed. This phenomenon of attentional blink (AB) has been widely studied to probe the temporal capacity of attention for detecting visual targets. However, with the typical procedure of AB experiments, it is not possible to examine how the processing of non-target items in RSVP may be affected by attention. This paper describes a novel dual task procedure combined with RSVP to test effects of AB for nontargets at varied stimulus onset asynchronies (SOAs). In an exemplar experiment, a target category was first displayed, followed by a sequence of 8 nouns. If one of the nouns belonged to the target category, participants would respond &#8216;yes&#8217; at the end of the sequence, otherwise participants would respond &#8216;no&#8217;. Two 2-alternative forced choice memory tasks followed the response to determine if participants remembered the words immediately before or after the target, as well as a random word from another part of the sequence. In a second exemplar experiment, the same design was used, except that 1) the memory task was counterbalanced into two groups with SOAs of either 120 or 240 msec and 2) three memory tasks followed the sequence and tested remembrance for nontarget nouns in the sequence that could be anywhere from 3 items prior the target noun position to 3 items following the target noun position. Representative results from a previously published study demonstrate that our procedure can be used to examine divergent effects of attention that not only enhance targets but also suppress nontargets. Here we show results from a representative participant that replicated the previous finding.&#160;

This paper describes a novel dual task procedure combined with Rapid Serial Visual Presentation to look at attentional blink at varied stimulus onset asynchronies. This experimental procedure differed from others in that it tested attentional blink for nontargets.

When viewers search for targets in a rapid serial visual presentation (RSVP) stream, if two targets are presented within about 500 msec of each other, the ...

Wheel Running and Environmental Complexity as a Therapeutic Intervention in an Animal Model of FASD

Aerobic exercise (e.g., wheel running (WR) extensively used in animal research) positively impacts many measures of neuroplastic potential in the brain, such as rates of adult neurogenesis, angiogenesis, and expression of neurotrophic factors in rodents. This intervention has also been shown to mitigate behavioral and neuroanatomical aspects of the negative impacts of teratogens (i.e., developmental exposure to alcohol) and age-related neurodegeneration in rodents. Environmental complexity (EC) has been shown to produce numerous neuroplastic benefits in cortical and subcortical structures and can be coupled with wheel running to increase the proliferation and survival of new cells in the adult hippocampus. The combination of these two interventions provides a robust &#34;superintervention&#34; (WR-EC) that can be implemented in a range of rodent models of neurological disorders. We will discuss the implementation of WR/EC and its constituent interventions for use as a more powerful therapeutic intervention in rats using the animal model of prenatal exposure to alcohol in humans. We will also discuss which elements of the procedures are absolutely necessary for the interventions and which ones may be altered depending on the experimenter&#39;s question or facilities.

Cardiovascular exercise and stimulating experiences in a complex environment have positive benefits on multiple measures of neuroplasticity within the rodent brain. This article will discuss the implementation of these interventions as a &#34;superintervention&#34; which combines wheel running and environmental complexity and will address the limitations of these interventions.

Aerobic exercise (e.g., wheel running (WR) extensively used in animal research) positively impacts many measures of neuroplastic potential in the brain, ...

A Within-subjects Experimental Protocol to Assess the Effects of Social Input on Infant EEG

Despite the importance of social interactions for infant brain development, little research has assessed functional neural activation while infants socially interact. Electroencephalography (EEG) power is an advantageous technique to assess infant functional neural activation. However, many studies record infant EEG only during one baseline condition. This protocol describes a paradigm that is designed to comprehensively assess infant EEG activity in both social and nonsocial contexts as well as tease apart how different types of social inputs differentially relate to infant EEG. The within-subjects paradigm includes four controlled conditions. In the nonsocial condition, infants view objects on computer screens. The joint attention condition involves an experimenter directing the infant's attention to pictures. The joint attention condition includes three types of social input: language, face-to-face interaction, and the presence of joint attention. Differences in infant EEG between the nonsocial and joint attention conditions could be due to any of these three types of input. Therefore, two additional conditions (one with language input while the experimenter is hidden behind a screen and one with face-to-face interaction) were included to assess the driving contextual factors in patterns of infant neural activation. Representative results demonstrate that infant EEG power varied by condition, both overall and differentially by brain region, supporting the functional nature of infant EEG power. This technique is advantageous in that it includes conditions that are clearly social or nonsocial and allows for examination of how specific types of social input relate to EEG power. This paradigm can be used to assess how individual differences in age, affect, socioeconomic status, and parent-infant interaction quality relate to the development of the social brain. Based on the demonstrated functional nature of infant EEG power, future studies should consider the role of EEG recording context and design conditions that are clearly social or nonsocial.

This novel protocol is designed to assess the neural bases of social interaction in infants. The paradigm is designed to tease apart how various social inputs such as language, joint attention, and face-to-face interaction relate to infant neural activation. Infant EEG power is recorded during both social and nonsocial conditions.

Despite the importance of social interactions for infant brain development, little research has assessed functional neural activation while infants ...

Using Virtual Reality to Transfer Motor Skill Knowledge from One Hand to Another

As far as acquiring motor skills is concerned, training by voluntary physical movement is superior to all other forms of training (e.g. training by observation or passive movement of trainee&#39;s hands by a robotic device). This obviously presents a major challenge in the rehabilitation of a paretic limb since voluntary control of physical movement is limited. Here, we describe a novel training scheme we have developed that has the potential to circumvent this major challenge. We exploited the voluntary control of one hand and provided real-time movement-based manipulated sensory feedback as if the other hand is moving. Visual manipulation through virtual reality (VR) was combined with a device that yokes left-hand fingers to passively follow right-hand voluntary finger movements. In healthy subjects, we demonstrate enhanced within-session performance gains of a limb in the absence of voluntary physical training. Results in healthy subjects suggest that training with the unique VR setup might also be beneficial for patients with upper limb hemiparesis by exploiting the voluntary control of their healthy hand to improve rehabilitation of their affected hand.

We describe a novel virtual-reality based setup which exploits voluntary control of one hand to improve motor-skill performance in the other (non-trained) hand. This is achieved by providing real-time movement-based sensory feedback as if the non-trained hand is moving. This new approach may be used to enhance rehabilitation of patients with unilateral hemiparesis.

As far as acquiring motor skills is concerned, training by voluntary physical movement is superior to all other forms of training (e.g. training by ...

Eye-tracking to Distinguish Comprehension-based and Oculomotor-based Regressive Eye Movements During Reading

Regressive eye movements are eye movements that move backwards through the text and comprise approximately 10-25% of eye movements during reading. As such, understanding the causes and mechanisms of regressions plays an important role in understanding eye movement behavior. Inhibition of return (IOR) is an oculomotor effect that results in increased latency to return attention to a previously attended target versus a target that was not previously attended. Thus, IOR may affect regressions. This paper describes how to design materials to distinguish between regressions caused by comprehension-related and oculomotor processes; the latter is subject to IOR. The method allows researchers to identify IOR and control the causes of regressions. While the method requires tightly controlled materials and large numbers of participants and materials, it allows researchers to distinguish and control the types of regressions that occur in their reading studies.

The method was designed to investigate the role of inhibition of return (IOR) in regressive eye movements during reading. The focus is on differentiating between regressions triggered as a result of comprehension difficulty versus those triggered from oculomotor error, including the role of IOR in the two types of regressions.

Regressive eye movements are eye movements that move backwards through the text and comprise approximately 10-25% of eye movements during reading. As ...

A View of Their Own: Capturing the Egocentric View of Infants and Toddlers with Head-Mounted Cameras

Infants and toddlers view the world, at a basic sensory level, in a fundamentally different way from their parents. This is largely due to biological constraints: infants possess different body proportions than their parents and the ability to control their own head movements is less developed. Such constraints limit the visual input available. This protocol aims to provide guiding principles for researchers using head-mounted cameras to understand the changing visual input experienced by the developing infant. Successful use of this protocol will allow researchers to design and execute studies of the developing child&#39;s visual environment set in the home or laboratory. From this method, researchers can compile an aggregate view of all the possible items in a child&#39;s field of view. This method does not directly measure exactly what the child is looking at. By combining this approach with machine learning, computer vision algorithms, and hand-coding, researchers can produce a high-density dataset to illustrate the changing visual ecology of the developing infant.

Infants and toddlers view the world in a fundamentally different way from their parents. Head-mounted cameras provide a tractable mechanism to understand the infant visual environment. This protocol provides guiding principles for experiments in the home or laboratory to capture the egocentric view of toddlers and infants.

Infants and toddlers view the world, at a basic sensory level, in a fundamentally different way from their parents. This is largely due to biological ...

Spotlighting Customers' Visual Attention at the Stock, Shelf and Store Levels with the 3S Model

Several models of the in-store search process exist in the fields of retailing, marketing, and consumer-based research. The present article presents a new conceptualization of this search process, which captures customers&#8217; visual attention at three distinct levels of analysis: Stock, Shelf, and Store. We refer to this conceptualization as the 3S Model and illustrate its usefulness through three eye-tracking studies, one from each level of analysis. Our experimental examples, which range from manipulating certain stimuli on a single product (e.g., the placement of textual and pictorial packaging elements) to manipulating the entire shopping trip for customers during their stay in a store (e.g., through more or less specific shopping tasks), highlight the broad applicability of this alternative approach for understanding customers&#8217; in-store search behavior. Thus, our model can be seen as a helpful tool for researchers interested in how to conduct experimental eye-tracking studies that shed light on the perceptual processes preceding product choices and purchase decisions. The 3S Model is equally suitable in controlled lab conditions and under ecologically valid settings in the real retail environment. Furthermore, it can be used from the micro level, with a focus on the meaningful metrics on a particular product, through the intermediate level, with the emphasis on the area surrounding products in shelves and other in-store spaces, all the way to the macro level, examining customers&#8217; navigational paths throughout a store as a function of their shopping tasks, cognitive capacity, or ability to acquire in-store information.

This article presents a new conceptualization of the in-store search process, the 3S Model, which captures customers&#8217; visual attention at three distinct levels of analysis: Stock, Shelf, and Store. We illustrate the usefulness of our conceptualization through three eye-tracking studies, one from each level of analysis in the 3S Model.

Several models of the in-store search process exist in the fields of retailing, marketing, and consumer-based research. The present article presents a new ...