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.

<ol>
	<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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The authors have nothing to disclose.

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 steps and trouble-shooting to help researchers that wish to implement this procedure in their studies.
One of the most critical steps to this procedure is having an error-free and rigorous survey/lexical decision task setup. Whether working with a survey building software, or implementing the survey manually using paper/pencil measures and a stopwatch to time participants completing beverage consumption, the clarity and accuracy of all procedures is paramount for both data collection and interpretation, and for maintaining control of the conditions across sessions. It is strongly recommended to proofread and pre-test all survey and lexical decision task measures for clarity and accuracy before data collection. It is best to engage multiple people (both familiar and blind to the hypothesis) to take the survey and offer feedback. Many survey building and experimental task building software companies also offer online message forums and troubleshooting help pages to help guide setting up and editing these survey measures and the lexical decision task. Accordingly, it is also important to have well-trained experimenters and research assistants helping with data collection and data entry. Write a session script with detailed instructions on session setup, scripted dialogue on how to communicate tasks to participants, and clearly outlined procedures for completing the experimental log. This will ensure that procedures are consistent across sessions, and across multiple experimenters that may be running the study. Additionally, another step to ensure that all participant data is accurate and linked properly by participant ID is to have double data entry procedures where two hypothesis blind research assistants separately enter and link the same data (see protocol section 6.1-6.2.1).
The methods presented in the current manuscript are significant for several reasons. First, the method for manipulating blood glucose is relatively simple and inexpensive to implement. Other methods of manipulating blood glucose such as a glucose tolerance test can cost a minimum of $26 to buy per person42. The current methods require, at minimum, that the researchers purchase of boxes of commercially available soft drinks (which can often be purchased in bulk at a discount). When the authors of this paper calculated the cost per participant for drinks (1 assigned drink) and blood testing supplies (2 lancets and 2 blood testing strips), plus factored in the cost of buying a blood glucometer to run the study, the calculated price per participant ranged from $1.34 to $3.34 (US dollars), depending upon where the supplies were purchased. Further, these methods have a proven track record of being able to change blood glucose enough to impact both cognitive and behavioral dependent measures16,20,22,43. Further, these methods have allowed researchers to test the effects of non-caloric artificial sweeteners, whose novel combination of sweet taste with no glucose may trigger unique changes in self-regulation20,22. Thus, using a simple blood glucose manipulation such as the one described can allow for research examining the complex interplay between one&#39;s physiological state and their changes in cognition and decision-making4,6,8,22. Additionally, the described lexical decision task provides a useful tool for measuring implicit changes in cognition that might be otherwise hard to test27. Together, these methods may be useful for nutrition researchers who wish to incorporate more self-report methods into their research, and for psychologists who wish to add more behavioral and physiological methods into their research.
Given that the incidence of overweight and obesity in the U.S. and the rest of the world has steadily increased for more than 30 years44-46, research on the psychological impact of blood glucose fluctuations on the processes that guide energy regulation represents an important domain of research for psychologists and nutritionists alike20,21,43. Although the changes in energy regulating decisions caused by blood glucose fluctuations at any given time may be small (such as picking a less healthy snack at the grocery store20), these small decisions can create surpluses in energy budget that add up to significant weight gain over a long period of time47. Therefore, examining the impacts of momentary blood glucose fluctuations on food related cognitions and health decision-making is a critical next step to build from the current self-regulation research. Thus, the current methodology offers an opportunity to both manipulate such fluctuations and measure changes in the subtle psychological underpinnings that may contribute to overweight and obesity.
The current methods have important limitations. One limitation of the methods is that the waiting period provided for blood glucose changes is at the shorter end of the range of&#160;acceptable time needed to allow for blood glucose change11,12,16. These methods were designed to balance the need to allow for energy change while also helping to minimize participant fatigue and discomfort. Although previously published research from the authors&#39; lab and other social psychologists showed consistent results using periods of 10 to 12 min11,12,18, others have found that it may be advantageous to wait 20 min or more after the drink manipulation before measuring the dependent variable4,8. For example, one could increase the delay by extending the time of the neutral filler task to allow for more time for change in blood glucose. The current methods are also limited in that they have not yet been tested or demonstrated effective in individuals with metabolic disorders (such as diabetes) or other health conditions associated with energy dysregulation (such as obesity). Thus, results cannot be generalized to obese individuals, and therefore must be treated with caution. Although investigating the underpinnings of calorie-regulation related cognition in healthy weight individuals represents a first step in investigating these processes, a critical next step will be to examine these effects in individuals who are obese (or who have dysregulated glucoregulation) and thus, may react to&#160;fluctuations in blood glucose differently than healthy weight individuals. Future research could benefit from trying to adapt these methods to safely investigate the effects of blood glucose change (and non-change) in such populations. This may mean making changes to the type of drink provided, time for blood glucose change allowed, or having proper medical equipment on hand to help re-balance blood glucose to safe levels if needed at conclusion of the research. Last, given that cognitive research has found that the facilitation effects of blood glucose are greatest in older adults1-3, it may be important to include age-diverse populations when running the current protocol. As the authors of this paper have not studied such populations yet (and have primarily relied on undergraduate populations to provide study samples), this paradigm cannot be seen as representing or generalizing to the effects of blood glucose fluctuations in older adult performance.
This manuscript provides a series of methods for manipulating changes in blood glucose and sample methods for a way to measure corresponding changes in cognition. It is the authors&#39; hope that these methods will help to increase interest in research examining the effects of energy fluctuation in cognition, decision-making, and behavior. The given methods provide a simple, and experimentally validated option to implementing such research. As such, they may be an important contribution to an ever growing area of research that is of interest to people across&#160;many research disciplines.

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 a blood-glucose manipulation procedure followed by a lexical decision task (see Table 1 for information about drinks used). At the conclusion of data collection, data from participants who did not meet the fasting preparation requirements [e.g. those who ate or drank anything besides water in less than eight hours prior to the experimental session (n = 18)] were excluded, leaving a total of 116 undergraduates in the final sample for analysis (75 women, 41 men; 36 in the Sprite condition (12 men), 40 in the Sprite Zero condition (14 men), and 40 in the mineral water condition (15 men)), aged 18 to 25 years (M = 19.81, SD = 3.27).
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Condition</td>
			<td>Energy/100g</td>
			<td>Drink Ingredients</td>
		</tr>
		<tr>
			<td>Sugar sweetened</td>
			<td>167 kJ/40 kcal</td>
			<td>Carbonated water, sugar, other sweetener (steviol glycosides), citric acid, malic acid, acidity regulator (sodium gluconate), lemon-lime flavorings (natural).</td>
		</tr>
		<tr>
			<td>Non-caloric sweetener</td>
			<td>0 kJ/0 kcal</td>
			<td>Carbonated water, citric acid, lemon-lime flavorings (natural), non-caloric sweeteners (aspartame, acesulfame-K), preservative (E211), acidity regulator (E331).</td>
		</tr>
		<tr>
			<td>Water</td>
			<td>0 kJ/0 kcal</td>
			<td>Carbonated water, natural flavors</td>
		</tr>
	</tbody>
</table>
Table 1: Characteristics of the Drinks Used Across All Studies. Table modified from original publication by Hill and colleagues20.
Data Analysis
First, participants&#39; lexical decision time data were cleaned and trimmed using the procedure outlined in protocol section 6 of this manuscript. The authors next created mean score composites for each word category (high fat, low fat, and non-word), using only the data from correct responses. The data for incorrect responses were not considered because faster reaction times for incorrect categorizations might simply be a result of random pecking on the keyboard, rather than reflecting differences in cognitive accessibility of a word, per se. Next, a preliminary 2 (Sex) x 3 (Drink) x 3 (Word Category) mixed model ANOVA was run to examine whether drink condition or participant sex influenced word categorization accuracy. Results demonstrated no differences in accuracy by drink condition across any word category (p = 0.25) and participant sex did not interact with any of the manipulated variables (ps &#8805;0.28). Thus, sex and accuracy variables were excluded from further analyses.
To test the hypothesis that non-calorically sweetened beverages (NCS) would increase the cognitive accessibility of high calorie, but not low calorie or non-word letter strings, a 3 x 3 mixed-model ANOVA was run, with drink type entered as the between-subjects factor and response word category (high calorie words, low calorie words, and non-words) entered as the within-subjects factor. Therefore, the authors expected that participants assigned to drink a non-calorically sweetened drink would have quicker reaction times when categorizing high calorie food words, but not when categorizing low calorie or non-food words. Results revealed that there was a significant interaction between drink type and response word category, F(4, 224) = 2.98, p = 0.02, &#951;p2 = 0.05 (see Figure 1). Next, to probe this interaction, the authors ran three separate ANCOVA models examining the effect of drink condition on an individual word category (e.g. high calorie words) and controlling for response times to each alternate word category while controlling for response times to each alternate word category. Bonferroni&#39;s correction (&#945; = .017) was applied to preserve alpha level and reduce any inflated likelihood of committing a Type 1 error due to running multiple, separate ANCOVA models. As predicted, unpacking the interaction revealed a significant main effect of drink type on participants&#39; reaction times to high calorie food words, F(2, 111) = 6.03, p = 0.003, &#951;p2 = 0.10. There were no effects of drink type on participants&#39; reaction times to low calorie food words, F(2, 111) = 1.93, p = 0.15), or non-words, F(2, 111) = 0.90, p = 0.41. Supplemental analyses run using a Sidak correction, in which the formula for calculating the new alpha cut-off is more conservative than a Bonferroni correction41 revealed the same cut-off value for alpha significance as the Bonferroni test, &#945; = 0.017, and thus re-confirmed the significance of our main effect.
Lastly, Helmert orthogonal planned contrasts (&#945; = 0.025) were conducted to probe any differences in reaction time between participants who consumed a NCS beverage and those who consumed sugar-sweetened or unsweetened drinks. The authors first compared participants in the NCS conditions&#39; reaction times to those of participants in both the sweetened and unsweetened drink conditions. Results revealed that participants who drank the NCS beverage responded more quickly to high calorie words than participants who drank sugar sweetened or unsweetened beverages (p = 0.001, CI: -84.89, -20.11). A final contrast was run to investigate if there were any differences in reaction times to high calorie words within the two control conditions (sugar sweetened vs.&#160;unsweetened beverages). Results revealed no differences in mean reaction time to high calorie words between participants who drank sugar sweetened or unsweetened beverages (p = 0.28).
The results of this research found that participants who consumed a beverage sweetened with NCS, compared to those who consumed a sugar-sweetened or unsweetened beverage, had shorter response latencies to the names of high-calorie food items than did those who had consumed a sugar-sweetened or unsweetened beverage. No such differences were found for the names of low-calorie food items or non-words, suggesting that drinking non-caloric sweeteners may increase cognitive accessibility (and hence, may reflect preoccupation) with high-calorie foods. These results suggest that consuming NCSs may influence implicit desires for calorie dense foods in ways that may encourage increased calorie consumption over time.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td colspan="2"></td>
			<td colspan="4">High Calorie</td>
			<td colspan="4">Low Calorie</td>
			<td colspan="4">Non Word</td>
		</tr>
		<tr>
			<td colspan="2"></td>
			<td>M</td>
			<td>SD</td>
			<td>Min</td>
			<td>Max</td>
			<td>M</td>
			<td>SD</td>
			<td>Min</td>
			<td>Max</td>
			<td>M</td>
			<td>SD</td>
			<td>Min</td>
			<td>Max</td>
		</tr>
		<tr>
			<td colspan="2">Words Correct</td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td colspan="2">Sweetened</td>
			<td>6.97</td>
			<td>0.17</td>
			<td>6</td>
			<td>7</td>
			<td>6.83</td>
			<td>0.38</td>
			<td>6</td>
			<td>7</td>
			<td>13.42</td>
			<td>1.02</td>
			<td>10</td>
			<td>14</td>
		</tr>
		<tr>
			<td colspan="2">Non Calorically Sweetened</td>
			<td>6.98</td>
			<td>0.16</td>
			<td>6</td>
			<td>7</td>
			<td>6.88</td>
			<td>0.34</td>
			<td>6</td>
			<td>7</td>
			<td>13.33</td>
			<td>1.23</td>
			<td>8</td>
			<td>14</td>
		</tr>
		<tr>
			<td colspan="2">Unsweetened</td>
			<td>6.85</td>
			<td>0.36</td>
			<td>6</td>
			<td>7</td>
			<td>6.75</td>
			<td>0.44</td>
			<td>6</td>
			<td>7</td>
			<td>13.33</td>
			<td>1.42</td>
			<td>7</td>
			<td>14</td>
		</tr>
	</tbody>
</table>
Table 2: Descriptive Statistics for Number of Letter Strings Categorized Correctly by Word Category and Drink Condition (Sugar Sweetened, Non-calorically Sweetened, and Unsweetened).
<img alt="Figure 1" src="/files/ftp_upload/54211/54211fig1.jpg" /> 
Figure 1: Reaction Time Results. Mean reaction time (in msec) of letter strings categorized correctly during a lexical decision task are plotted by word category and drink condition. Longer reaction time latencies indicate lesser cognitive accessibility of a word category. Error bars reflect the standard error of the adjusted means. Only the comparisons of drink group within the high calorie condition are significant. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54211/54211fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

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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 ...

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8.9K Views.  Texas Christian University. The authors introduce a method for manipulating blood glucose and measuring resulting changes in cognitive accessibility of target words using a lexical decision task.

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

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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 ...

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 ...

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

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

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

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

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