The authors wish to acknowledge the support of Florida International University and the Center for Children and Families.

This protocol follows Florida International University&#8217;s guidelines for research with human subjects and consent is always obtained from parents/caregivers before any treatment is started. In addition, obtain clearance from a physician before the start of treatment. &#160;
NOTE: Although specific age ranges and individual variables have not been empirically validated, this protocol has been used clinically for children ages 2-7 with autism and developmental delays. Participants should be referred for behavioral intervention by their caregiver and a medical professional. Clear participants of any medical or physical underlying issues related to feeding as part of the screening for eligibility for behavioral intervention protocols to address food selectivity.
1. Session Structure and Clinical Environment
<ol>
	<li>Conduct treatment sessions in an outpatient treatment setting, between two and four times per week, for approximately 1 hr per session. Conduct sessions in treatment rooms equipped with a table, chairs, and items that are used during mealtimes (i.e., plates, napkins and utensils). Additionally, bring toys and other tangible items into the room to serve as reinforcers throughout out the intervention procedure.</li>
</ol>
2. Pre-treatment Assessments
<ol>
	<li>Preference Assessment.</li>
	<li>Conduct a brief, informal preference assessment at the start of each session, to determine tangible items that may function as reinforcers for compliance during that session. Present an array of toys on the table and the give the child the opportunity to choose the toys he/she wants to work for that day.</li>
	<li>Food Assessment
	<ol>
		<li>Ask parents or caregivers to indicate foods that the child is likely to eat 100% of the time when they are offered, 80% of the time, 60% of the time, and so on down to those foods the child would not accept (0%) in twenty percent increments.</li>
		<li>Begin the intervention with those foods the child is likely to eat (100% of the time when offered) and proceeded to more difficult foods that the child has never tried. &#160; 
		NOTE: The purpose of including a preferred (100%) food in the first intervention condition is to initially foster compliance with the demand fading steps.</li>
	</ol>
	</li>
</ol>
3. Sessions and Procedures
<ol>
	<li>During baseline present a bite of each of the target foods that have not yet been exposed to the intervention on a white plate in front of the child and say, &#8220;Eat this.&#8221; Do not provide any consequences contingent on any response emitted during baseline.</li>
	<li>If the child eats the food, then allow them time to consume it and then present the next bite. If the child does not eat the food after 10 sec the trials ends and then present the next food. &#160; 
	NOTE: Present each food should 5 times during baseline in an alternating order. Conduct at least 2 baseline sessions prior to beginning intervention for any target food. Continue to probe the remaining foods in baseline at least one time per week.</li>
	<li>Confirm parent report of the child&#8217;s food preferences by placing one food from each category (i.e., 100%, 80%, etc.) on a white plate in front of the child and say, &#8220;Eat this.&#8221; Present each of the foods five times in an alternating order. If the child eats the food, move on to the next trial. If the child does not eat the food after 10 sec, remove it from the plate and present the next food item. If the child throws the food or says they do not want it move on to the next food item without addressing the problem behavior. &#160; 
	NOTE: Only use those foods that are consistent with parent report for intervention. If there are foods that do not match the parent report, for example the parent reports that the child eats an item 20% of the time and they eat it 100% of the time during this phase, do not include this food as a target for intervention.</li>
	<li>Intervention Sessions.</li>
	<li>Conduct all treatment sessions as trials (rather than time based) and a session includes five trials. A trial begins when the target food is placed on the placemat and the instruction is delivered. A trial ends contingent on compliance or after 10s of noncompliance. Vary the number of sessions completed during each 1 hr visit depending on child variables and characteristics, including compliance with instructions. &#160; 
	NOTE: The mastery criterion for each step in the intervention is 80% or higher of compliance across two consecutive sessions. Compliance is defined as completing the presented task within 10 sec from the time the instruction is delivered.</li>
</ol>
4. Treatment Package
NOTE: The treatment package consists of shaping and sequential and simultaneous presentation procedures.
<ol>
	<li>Shaping
	<ol>
		<li>Implement a shaping procedure for each target food, where successive approximations to eating are reinforced. The shaping procedure is composed of seven steps; a) put the food in therapist&#8217;s hand, b) touch the food to the child&#8217;s cheek, c) touch food to nose; d) touch food to lips; e) touch food to tongue; f) bite down on food; g) eat food (i.e., mouth clean [swallowing the food so that none of it remains in the child&#8217;s mouth]). &#160; 
		NOTE: During each step the child has to complete the target behavior independently (e.g., the child has to put the food in the therapist&#8217;s hand).</li>
	</ol>
	</li>
	<li>Sequential Presentation
	<ol>
		<li>Use a placemat containing two different colored circles to serve as a visual representation of the sequential presentation procedure. Always place target foods on the left and less preferred foods on the right side of the placemat. &#160; 
		NOTE: This presentation is designed to foster predictability in the procedure and to acquire stimulus control for compliance with foods presented on the left side.</li>
		<li>Additionally, place preferred tangible items on the right side of the placemat. Use the prompt, &#8220;First [shaping step] then [name of preferred food and tangible]&#8221; to introduce the instruction for the sequential presentation procedure. For example, &#8220;first touch the pea to your nose and then you can have your cookie and crayons.&#8221;</li>
	</ol>
	</li>
	<li>Simultaneous Presentation
	<ol>
		<li>Present both the preferred and non-preferred foods together during the simultaneous procedure. Specifically, place the non-preferred food on top of the preferred food (e.g., a grain of rice is placed on top of a chip) and place this combination on the left side of the placemat.</li>
		<li>Place preferred tangible and edible items on the right side of the placemat, as is done in the sequential procedure. Slowly increase the amount of non-preferred food placed on top of the preferred food until equal amounts of non-preferred and preferred foods are presented.</li>
		<li>Present all foods in bite size pieces. Use pieces that are small enough that the child can consume it with one bite, but large enough so that the child will need to chew it several times before swallowing. Present foods with or without a utensil depending on individual needs. Require that participants feed themselves during all sessions.</li>
	</ol>
	</li>
</ol>
5. Intervention
<ol>
	<li>Training Phase (Preferred Food) 
	NOTE: Use the most preferred food (i.e., the food identified as most likely to be eaten 100% of the time in the food assessment) during the training phase, aimed at facilitating familiarity with and compliance with the steps in the shaping sequence.
	<ol>
		<li>Begin the training phase with the initial step of placing the food in the examiner&#8217;s hand and continue until the child reaches the mastery criterion (i.e., at least 80% compliance across two consecutive sessions) for the final step (i.e., eating).</li>
	</ol>
	</li>
	<li>Shaping and Sequential Presentation
	<ol>
		<li>Use the next food identified in the food assessment (child is likely to eat 80% of the time when offered) for this phase of the intervention. During each session, the participant and therapist sit side by side at the table.</li>
		<li>Place the placemat in front of the child and all food and tangible items are placed on the table next to the therapist.</li>
		<li>Begin each trial by placing the target food on the left side of the placemat and the potential reinforcers on the right side. The therapist then provides the first-then prompt.</li>
		<li>Contingent on compliance, allow the child to have access to the reinforcers (consumption of preferred food and access to tangible item for approximately 30 sec). Contingent on noncompliance (not completing the target behavior within 10 sec or throwing the target food), represent the first-then prompt.</li>
		<li>Begin this phase with step 1 of the shaping procedure (put the food in therapist&#8217;s hand) and tell the participant &#8220;first put ___in my hand and then you can have (reinforcer).&#8221; Continue until the mastery criteriais met (80% or higher compliance across two consecutive sessions).</li>
		<li>Move to step 2 of the shaping procedure (touch the food to the child&#8217;s cheek) when mastery criteria are met. Continue sessions in this manner until the last step of eating the food is mastered. Introduce the next food identified at this point starting with step 1 of the shaping procedure and repeating the shaping steps as described.</li>
	</ol>
	</li>
	<li>Shaping, Sequential, and Simultaneous Presentation 
	NOTE: Introduce a simultaneous presentation phase in instances when shaping and sequential presentation are not effective in increasing compliance for the last step in the shaping sequence (i.e., mouth clean).
	<ol>
		<li>Begin this phase by first combining the two foods so that the non-preferred food is not visible to the child. For example, place the non-preferred food inside of the preferred and placed on the placemat so that the child cannot see the non-preferred food.</li>
		<li>Systematically increase the size of the non-preferred food and decrease the preferred food until the non-preferred food is presented alone. The ratio of the two foods (i.e., preferred and non-preferred) is systematically changed when compliance reaches 80% or better across two consecutive sessions. Continue to use the placemat and first-then prompt in this phase.</li>
	</ol>
	</li>
</ol>
6. Data
<ol>
	<li>Record yes or no data on compliance for each trial. A trial begins when the if-then prompt is delivered and compliance is defined as initiating the behavior within 10 sec from the time the prompt is presented.</li>
	<li>Make separate graphs for each target food with the independent variable being the session (i.e., 5 trials) and the dependent variable the percent compliance for the session. Enter the percent compliance in spreadsheet in order to create a graphical display of the session data in a spreadsheet. Enter the data into columns.</li>
	<li>Then select the data, click Insert then Chart. When the chart choices are presented select the marked line chart choice. Draw vertical lines between the phases of the procedure. Insert a text box with the label &#8220;baseline&#8221; above the data for the baseline sessions.</li>
	<li>Insert a text box with a number corresponding to the step of the procedure at the top of the figure for each step of the procedure. Place a label at the top of the chart denoting which food is being displayed (e.g., &#8220;100% food&#8221;, &#8220;80% food). Copy and paste the first chart at the top of a blank page and copy and paste the subsequent charts below in order.</li>
</ol>

<ol><li>Ahearn, W. H., Kerwin, M. E., Eicher, P. S., Shantz, J., Swearingin, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((An+alternating+treatments+comparison+of+two+intensive+interventions+for+food+refusal%5BTitle%5D)+AND+%22Journal+of+Applied+Behavior+Analysis%22%5BJournal%5D)">An alternating treatments comparison of two intensive interventions for food refusal.</a> Journal of Applied Behavior Analysis. 29 (3), 321-332 (1996).</li>
<li>Bandini, L. G., Anderson, S. E., Curtin, C., Cermak, S., Evans, E. W., Scampini, R., Must, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Food+selectivity+in+children+with+autism+spectrum+disorders+and+typically+developing+children%5BTitle%5D)+AND+%22The+Journal+of+Pediatrics%22%5BJournal%5D)">Food selectivity in children with autism spectrum disorders and typically developing children.</a> The Journal of Pediatrics. 157 (2), 259-265 (2010).</li>
<li>Bachmeyer, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Treatment+of+selective+and+inadequate+food+intake+in+children%3A+A+review+and+practical+guide%5BTitle%5D)+AND+%22Behavior+Analysis+in+Practice%22%5BJournal%5D)">Treatment of selective and inadequate food intake in children: A review and practical guide.</a> Behavior Analysis in Practice. 2 (1), 43-50 (2009).</li>
<li>Cermak, S. A., Curtin, C., Bandini, L. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Food+selectivity+and+sensory+sensitivity+in+children+with+autism+spectrum+disorders%5BTitle%5D)+AND+%22Journal+of+the+American+Dietetic+Association%22%5BJournal%5D)">Food selectivity and sensory sensitivity in children with autism spectrum disorders.</a> Journal of the American Dietetic Association. 110 (2), 238-246 (2010).</li>
<li>Cooper, L. J., Wacker, D. P., Brown, K., McComas, J. J., Peck, S. M., Drew, J., Asmus, J., Kayser, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Use+of+concurrent+operants+paradigm+to+evaluate+positive+reinforcers+during+treatment+of+food+refusal%5BTitle%5D)+AND+%22Behavior+Modification%22%5BJournal%5D)">Use of concurrent operants paradigm to evaluate positive reinforcers during treatment of food refusal.</a> Behavior Modification. 23 (1), 3-40 (1999).</li>
<li>Dawson, J. E., Piazza, C. C., Sevin, B. M., Gulotta, C. S., Lerman, D., Kelley, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Use+of+the+high-probability+instructional+sequence+and+escape+extinction+in+a+child+with+food+refusal%5BTitle%5D)+AND+%22Journal+of+Applied+Behavior+Analysis%22%5BJournal%5D)">Use of the high-probability instructional sequence and escape extinction in a child with food refusal.</a> Journal of Applied Behavior Analysis. 36 (1), 105-108 (2003).</li>
<li>Dovey, T. M., Staples, P. A., Gibson, E. L., Halford, J. C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Food+neophobia+and+%27picky%2Ffussy+eating+in+children%3A+A+review%5BTitle%5D)+AND+%22Appetite%22%5BJournal%5D)">Food neophobia and 'picky/fussy eating in children: A review.</a> Appetite. 50, 181-193 (2008).</li>
<li>Kern, L., Marder, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+comparison+of+simultaneous+and+delayed+reinforcement+as+treatments+for+food+selectivity%5BTitle%5D)+AND+%22Journal+of+Applied+Behavior+Analysis%22%5BJournal%5D)">A comparison of simultaneous and delayed reinforcement as treatments for food selectivity.</a> Journal of Applied Behavior Analysis. 29 (2), 243-246 (1996).</li>
<li>Ledford, J. R., Gast, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Feeding+problems+in+children+with+autism+spectrum+disorders%3A+A+review%5BTitle%5D)+AND+%22Focus+on+Autism+and+Other+Developmental+Disabilities%22%5BJournal%5D)">Feeding problems in children with autism spectrum disorders: A review.</a> Focus on Autism and Other Developmental Disabilities. 21 (3), 153-166 (2006).</li>
<li>Munk, D. D., Repp, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Behavioral+assessment+of+feeding+problems+of+individuals+with+severe+disabilities%5BTitle%5D)+AND+%22Journal+of+Applied+Behavior+Analysis%22%5BJournal%5D)">Behavioral assessment of feeding problems of individuals with severe disabilities.</a> Journal of Applied Behavior Analysis. 27 (2), 241-250 (1994).</li>
<li>Patel, M. R., Piazza, C. C., Martinez, C. J., Volkert, V. M., Santana, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((An+evaluation+of+two+differential+reinforcement+procedures+with+escape+extinction+to+treat+food+refusal%5BTitle%5D)+AND+%22Journal+of+Applied+Behavior+Analysis%22%5BJournal%5D)">An evaluation of two differential reinforcement procedures with escape extinction to treat food refusal.</a> Journal of Applied Behavior Analysis. 35 (4), 363-374 (2002).</li>
<li>Penrod, B., Gardella, L., Fernand, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((An+evaluation+of+a+progressive+high-probability+instructional+sequence+combined+with+low+probability+demand+fading+in+the+treatment+of+food+selectivity%5BTitle%5D)+AND+%22Journal+of+Applied+Behavior+Analysis%22%5BJournal%5D)">An evaluation of a progressive high-probability instructional sequence combined with low probability demand fading in the treatment of food selectivity.</a> Journal of Applied Behavior Analysis. 45 (3), 527-537 (2012).</li>
<li>Piazza, C. C., Patel, M. R., Santana, C. M., Goh, H., Delia, M. D., Lancaster, B. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((An+evaluation+of+simultaneous+and+sequential+presentation+of+preferred+and+non-preferred+food+to+treat+food+selectivity%5BTitle%5D)+AND+%22Journal+of+Applied+Behavior+Analysis%22%5BJournal%5D)">An evaluation of simultaneous and sequential presentation of preferred and non-preferred food to treat food selectivity.</a> Journal of Applied Behavior Analysis. 35 (3), 259-270 (2002).</li>
<li>Pizzo, B., Coyle, M., Seiverling, L., Williams, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Plate+a-plate+b%3A+Use+of+sequential+presentation+in+the+treatment+of+food+selectivity%5BTitle%5D)+AND+%22Behavioral+Interventions%22%5BJournal%5D)">Plate a-plate b: Use of sequential presentation in the treatment of food selectivity.</a> Behavioral Interventions. 27, 175-184 (2012).</li>
<li>Tarbox, J., Schiff, A., Najdowski, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Parent-Implemented+procedural+modification+of+escape+extinction+in+the+treatment+of+food+selectivity+in+a+young+child+with+autism%5BTitle%5D)+AND+%22Education+and+Treatment+of+Children%22%5BJournal%5D)">Parent-Implemented procedural modification of escape extinction in the treatment of food selectivity in a young child with autism.</a> Education and Treatment of Children. 33 (2), 223-234 (2010).</li>
</ol>

The authors declare that they have no competing financial interests.

This paper presents a treatment package composed of antecedent manipulations that have demonstrated success in increasing food acceptance for children who exhibit food selectivity. Notably, this paper presents a set of procedures that may be effective without the use of escape extinction. These methods are consistent with previous literature (Penrod et al., 2012) that suggests that a shaping procedure can be used to increase food acceptance with children who engage in active food refusal (e.g., throwing...

Food selectivity, defined as a reluctance to try new foods based on some dimension of the food (e.g., texture, color, or presentation) often characterizes the feeding behavior of young children with autism spectrum disorders (ASD) and other developmental delays2,4,7,10.
Although children who exhibit food selectivity often eat some foods, these foods are frequently limited in variety (e.g., snacks and carbohydrates) and may not provide adequate nutrition. Food selectivity may never lead to total food refusal requiring medical attention (e.g., a diagnosis of failure to thrive or the insertion of a gastric feeding tube) however, the limited food repertoires of children with food selectivity may lead to nutritional inadequacies.
An effective intervention to increase food acceptance in children with acute food selectivity is escape extinction, in the forms of non-removal of the spoon and/or physical guidance1,6,11.
Children who engage in severe maladaptive feeding behavior often engage in total food refusal that leads to limited weight gain and growth and may require the use of gastric-tube feedings. When a child&#8217;s feeding behavior is impacting their development, escape extinction may be essential to quickly increase food acceptance. For example, Cooper and colleagues5 found that escape extinction was a necessary component in the treatment packages of 3 of 4 participants who all exhibited poor growth and engaged in tantrum behavior (e.g., gagging, spitting and screaming) when food was presented.
Escape extinction has been repeatedly demonstrated as a valuable component in treatment packages for children with chronic feeding problems, however; these procedures may not be necessary for children who engage in less severe feeding behavior (i.e., food selectivity). Children who engage in severe feeding behavior may differ from children who engage in food selectivity, in that severe feeding behavior may involve total food refusal where as children with food selectivity may consume some foods, although limited in range and nutritional value.
Consistent consumption of even a limited number of foods may lead to children being responsive to reinforcement-based interventions that do not require the addition of escape extinction. For children with autism, positive reinforcement procedures are viewed as best practice9 and should be implemented in the treatment of food selectivity when the child&#8217;s behavior may not warrant the use of escape extinction. Recent research on the use of antecedent manipulations and positive reinforcement methodologies as possible alternatives to the use of escape extinction suggest that these methods may be effective for some children who exhibit food selectivity3,11,12.
Studies evaluating the use of antecedent manipulations to treat food selectivity have incorporated a variety of procedures including, high-p sequences6,11,12, and sequential and simultaneous food presentation1,8,13. Results of studies evaluating these procedures have shown that antecedent manipulations are effective in increasing food acceptance for children who engage in food selectivity12,14. For example, Penrod and colleagues12 effectively increased food consumption in two children diagnosed with ASD who engaged in active food refusal (e.g., spitting, gagging and vomiting), using a treatment package consisting of a high-p sequence and demand fading procedure.
The way in which preferred and non-preferred foods are presented (e.g., sequential versus simultaneous presentation) may also contribute to the effectiveness of treatment packages for children who engage in food selectivity. Both sequential (i.e., presenting the non-preferred food followed by the preferred food) and simultaneous (i.e., combining a non-preferred and preferred food together) presentation methods have demonstrated some success in increasing food acceptance13,14. For example, Piazza et al.13, found that the simultaneous presentation procedure, without escape extinction was effective in increasing food acceptance in 3 of 4 participants and that sequential presentation was ineffective for 2 participants. In contrast, Pizzo and colleagues14 successfully used a treatment package consisting of sequential presentation and appetite manipulation to increase food acceptance in a 16-year-old boy with ASD. While the degree to which these presentation procedures are successful without the addition of escape extinction is unclear; some studies suggest that these procedures may be an effective antecedent manipulation for some children. More research is required to determine the utility of both sequential and simultaneous procedures in treatment packages that do not include an escape extinction component.
In designing treatment packages for children who engage in food selectivity, it is important to consider the differences between children who eat a limited number of foods and those who engage in total food refusal as this may impact responsiveness to intervention. For children who engage in food selectivity, parents and clinicians may be less willing to implement intrusive escape extinction procedures since they may not view the child&#8217;s behavior as severe enough to warrant these interventions. Tarbox, Schiff and Najdowski15 suggest that anecdotal reports indicate that escape extinction procedures may be difficult for parents to accept. The authors propose that it may be useful to evaluate the effectiveness of other behavioral treatment procedures that may be less intrusive for cases where escape extinction may be not accepted by the parents.
Results from the studies reviewed provide evidence that antecedent manipulations are an important and powerful component to treatment packages for food selectivity. Antecedent manipulations may take many forms (e.g., high-p sequences and sequential and simultaneous food presentation) and it is important that research focuses on which components may be combined in treatment packages to effectively increase food acceptance without the addition of escape extinction; as these interventions may provide less intrusive alternatives when escape extinction procedures are not necessary. This manuscript describes a treatment package that combines shaping, sequential and simultaneous presentation procedures. These procedures have been effective in increasing food acceptance when combined with other antecedent manipulations but have not previously been combined in a treatment package. The current protocol extends the literature on sequential and simultaneous presentation procedures by including them in a treatment package with a shaping procedure that may serve as a first line of treatment that could be implemented by parents, teachers, and clinicians with limited training before seeking more intensive treatment.

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a treatment package without escape extinction to address food selectivity

Feeding difficulties and feeding disorders are a commonly occurring problem for young children, particularly children with developmental delays including autism. Behavior analytic interventions for the treatment of feeding difficulties oftentimes include escape extinction as a primary component of treatment. The use of escape extinction, while effective, may be problematic as it is also associated with the emergence of challenging behavior (e.g., extinction burst). Such challenging behavior may be an acceptable side effect in treatment cases where feeding problems are severe and chronic (e.g., failure to thrive). However, in more acute cases (e.g., selective eating), the negative side effect may be unwarranted and undesired. More recent research on the behavioral treatment of food selectivity has begun to evaluate treatments for feeding difficulties that do not include escape extinction (e.g., demand fading, behavioral momentum), with some success. However, research to date reveals individual differences in responsiveness to such treatments and no clear preferable treatment has emerged. This manuscript describes a multi-component treatment package that includes shaping, sequential presentation and simultaneous presentation, for the treatment of food selectivity in four young children with developmental delays. This treatment package extends the literature on the behavioral treatment for food selectivity and offers a multi-component treatment protocol that may be clinically applicable across a range of treatment scenarios and settings.

The procedure of shaping and sequential presentation described can result in initial compliance with behaviors related to eating (e.g., touching the food) that can be strengthened through the use of reinforcement and shaping. By reinforcing successive approximations (shaping steps) behavior can be shaped slowly until reaching the target behavior of eating. The results depicted in Figure 1 show that the technique of shaping is capable of increasing compliance with food acceptance and the steps in...

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A Treatment Package without Escape Extinction to Address Food Selectivity

Feeding difficulties are a common problem for children with developmental disorders, including autism, and behavioral interventions often include escape extinction. Recent research has begun to evaluate treatments that do not include escape extinction. This manuscript describes a multicomponent treatment package that does not use escape extinction to treat feeding difficulties.

Feeding difficulties and feeding disorders are a commonly occurring problem for young children, particularly children with developmental delays including ...

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11.5K Views.  Florida International University. Feeding difficulties are a common problem for children with developmental disorders, including autism, and behavioral interventions often include escape extinction. Recent research has begun to evaluate treatments that do not include escape extinction. This manuscript describes a multicomponent treatment package that does not use escape extinction to treat feeding difficulties.

Video: A Treatment Package without Escape Extinction to Address Food Selectivity

The Attentional Set Shifting Task: A Measure of Cognitive Flexibility in Mice

Cognitive impairment, particularly involving dysfunction of circuitry within the prefrontal cortex (PFC), represents a core feature of many neuropsychiatric and neurodevelopmental disorders, including depression, post-traumatic stress disorder, schizophrenia and autism spectrum disorder. Deficits in cognitive function also represent the most difficult symptom domain&#160;to successfully treat, as serotonin reuptake inhibitors and tricyclic antidepressants have only modest effects. Functional neuroimaging studies and postmortem analysis of human brain tissue implicate the PFC as being a primary region of dysregulation in patients with these disorders. However, preclinical behavioral assays used to assess these deficits in mouse models which can be readily manipulated genetically and could provide the basis for studies of new treatment avenues have been underutilized. Here we describe the adaptation of a behavioral assay, the attentional set shifting task (AST), to be performed in mice to assess prefrontal cortex mediated cognitive deficits. The neural circuits underlying behavior during the AST are highly conserved across humans, nonhuman primates and rodents, providing excellent face, construct and predictive validity.

The goal of this protocol is to perform a behavioral assay such as the attentional set shifting task (AST) to assess prefrontal cortex-mediated cognitive flexibility in mice.

Cognitive impairment, particularly involving dysfunction of circuitry within the prefrontal cortex (PFC), represents a core feature of many ...

How to Create Conditioned Taste Aversion for Grazing Ground Covers in Woody Crops with Small Ruminants

Conditioned taste aversion (CTA) is a learning behavior process where animals are trained to reject certain feed after gastrointestinal discomfort has been produced. Lithium chloride (LiCl) is the preferred agent used in livestock to induce CTA because it specifically stimulates the vomit center. In addition, LiCl is commercially available, and easy to prepare and administer using a drenching gun. Nevertheless, some factors have to be considered to obtain an effective long-lasting CTA, which allows small ruminants to graze during the cropping season. A key aspect is to use animals with no previous contact with the target plant (the plant chosen to be avoided; new feed). Due to their native neophobic feeding behavior, small ruminants can easily associate the negative feedback effects with the new feed, resulting in a strong and persistent CTA. The recommended doses are 200 and 225 mg LiCl/kg body weight (BW) for goats and sheep, respectively. To induce CTA, 100 g of the target plant should be individually offered for at least 30 min, and LiCl administered thereafter if the intake is greater than 10 g. Each time the animal eats the target plant without negative consequences, the CTA becomes weaker. Consequently, to minimize the risk of target plant consumption, it is essential to have sufficient palatable ground cover available. The presence of an alternative feed (of quality and quantity) prevents the accidental consumption of the target plant. A close monitoring of the flock is recommended to remove and re-dose any animal consuming more than 4 bites or 10 g of the target plant. At the beginning of each grazing season, check the CTA status of each animal before moving them to the crop.

Feeding behavior preferences in livestock can be modified to implement a grazing management plan in woody crops. Here, we present a protocol to show a lithium chloride dose after eating a new plant that induces conditioned taste aversion.

Conditioned taste aversion (CTA) is a learning behavior process where animals are trained to reject certain feed after gastrointestinal discomfort has ...

Environment

Signal Attenuation as a Rat Model of Obsessive Compulsive Disorder

In the signal attenuation rat model of obsessive-compulsive disorder (OCD), lever-pressing for food is followed by the presentation of a compound stimulus which serves as a feedback cue. This feedback is later attenuated by repeated presentations of the stimulus without food (without the rat emitting the lever-press response). In the next stage, lever-pressing is assessed under extinction conditions (i.e., no food is delivered). At this stage rats display two types of lever-presses, those that are followed by an attempt to collect a reward, and those that are not. The latter are the measure of compulsive-like behavior in the model. A control procedure in which rats do not experience the attenuation of the feedback cue serves to distinguish between the effects of signal attenuation and of extinction. The signal attenuation model is a highly validated model of OCD and differentiates between compulsive-like behaviors and behaviors that are repetitive but not compulsive. In addition the measures collected during the procedure eliminate alternative explanations for differences between the groups being tested, and are quantitative, unbiased and unaffected by inter-experimenter variability. The major disadvantages of this model are the costly equipment, the fact that it requires some technical know-how and the fact that it is time-consuming compared to other models of OCD (11 days). The model may be used for detecting the anti- or pro-compulsive effects of pharmacological and non-pharmacological manipulations and for studying the neural substrate of compulsive behavior.

The goal of the protocol described in this paper is to induce compulsive-like behavior in rats for the study of obsessive-compulsive disorder (OCD). This behavior is precipitated by attenuating a signal indicating that a lever-press response was effective in producing food.

In the signal attenuation rat model of obsessive-compulsive disorder (OCD), lever-pressing for food is followed by the presentation of a compound stimulus ...

Errors as a Means of Reducing Impulsive Food Choice

Nowadays, the increasing incidence of eating disorders due to poor self-control has given rise to increased obesity and other chronic weight problems, and ultimately, to reduced life expectancy. The capacity to refrain from automatic responses is usually high in situations in which making errors is highly likely. The protocol described here aims at reducing imprudent preference in women during hypothetical intertemporal choices about appetitive food by associating it with errors. First, participants undergo an error task where two different edible stimuli are associated with two different error likelihoods (high and low). Second, they make intertemporal choices about the two edible stimuli, separately. As a result, this method decreases the discount rate for future amounts of the edible reward that cued higher error likelihood, selectively. This effect is under the influence of the self-reported hunger level. The present protocol demonstrates that errors, well known as motivationally salient events, can induce the recruitment of cognitive control, thus being ultimately useful in reducing impatient choices for edible commodities.

Giving in to temptation of tasty food may result in long-term overweight problems. This protocol describes how to reduce imprudent preference for edible commodities during hypothetical intertemporal choices in women by associating them with errors.

Nowadays, the increasing incidence of eating disorders due to poor self-control has given rise to increased obesity and other chronic weight problems, and ...

A General Method for Evaluating Incubation of Sucrose Craving in Rats

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

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

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

Neuroscience

Assessment of Social Transmission of Food Preferences Behaviors

Olfactory recognition deficits are suggested to be able to serve as clinical marker to differentiate Alzheimer&#39;s disease (AD) subjects from healthy aging groups. For example, olfactory dysfunction in AD can present as impairment in olfactory recognition, emerging during early stages of the disease and worsening while the disease progresses. The social transmission of food preferences (STFP) task is based on a rudimentary form of communication between rodents concerning distant foods dependent on the transmission of olfactory cues. Healthy wild-type mice would prefer to eat a novel, flavored food that was previously cued by a conspecific, and this food preference would be hampered in transgenic AD mice, such as the APP/PS1 model. Indeed, a strong preference for the cued food in C57Bl6/J mice of 3 months of age was found, and this was reduced in 3 months old transgenic APP/PS1 mice. In summary, STFP task could be a powerful measure to be integrated in present subclinical detection assays of AD.

This paper presents a protocol for the investigation of social transmission of food preference in mice. The advantages and possible applications for this procedure, for instance, in detecting early changes in AD mouse models, are highlighted. To conclude, interpretation of the results in light of critical details are discussed.

Olfactory recognition deficits are suggested to be able to serve as clinical marker to differentiate Alzheimer&#39;s disease (AD) subjects from healthy ...

Progressive-ratio Responding for Palatable High-fat and High-sugar Food in Mice

Foods that are rich in fat and sugar significantly contribute to over-eating and escalating rates of obesity. The consumption of palatable foods can produce a rewarding effect that strengthens action-outcome associations and reinforces future behavior directed at obtaining these foods. Increasing evidence that the rewarding effects of energy-dense foods play a profound role in overeating and the development of obesity has heightened interest in studying the genes, molecules and neural circuitry that modulate food reward1,2. The rewarding impact of different stimuli can be studied by measuring the willingness to work to obtain them, such as in operant conditioning tasks3. Operant models of food reward measure acquired and voluntary behavioral responses that are directed at obtaining food. A commonly used measure of reward strength is an operant procedure known as the progressive ratio (PR) schedule of reinforcement.4,5 In the PR task, the subject is required to make an increasing number of operant responses for each successive reward. The pioneering study of Hodos (1961) demonstrated that the number of responses made to obtain the last reward, termed the breakpoint, serves as an index of reward strength4. While operant procedures that measure changes in response rate alone cannot separate changes in reward strength from alterations in performance capacity, the breakpoint derived from the PR schedule is a well-validated measure of the rewarding effects of food. The PR task has been used extensively to assess the rewarding impact of drugs of abuse and food in rats (e.g.,6-8), but to a lesser extent in mice9. The increased use of genetically engineered mice and diet-induced obese mouse models has heightened demands for behavioral measures of food reward in mice. In the present article we detail the materials and procedures used to train mice to respond (lever-press) for a high-fat and high-sugar food pellets on a PR schedule of reinforcement. We show that breakpoint response thresholds increase following acute food deprivation and decrease with peripheral administration of the anorectic hormone leptin and thereby validate the use of this food-operant paradigm in mice.

The present report details the protocol employed to measure the rewarding effects of high-fat food in mice using a progressive ratio operant conditioning task.

Foods that are rich in fat and sugar significantly contribute to over-eating and escalating rates of obesity. The consumption of palatable foods can ...

Extinction Training During the Reconsolidation Window Prevents Recovery of Fear

Fear is maladaptive when it persists long after circumstances have become safe. It is therefore crucial to develop an approach that persistently prevents the return of fear. Pavlovian fear-conditioning paradigms are commonly employed to create a controlled, novel fear association in the laboratory. After pairing an innocuous stimulus (conditioned stimulus, CS) with an aversive outcome (unconditioned stimulus, US) we can elicit a fear response (conditioned response, or CR) by presenting just the stimulus alone1,2 . Once fear is acquired, it can be diminished using extinction training, whereby the conditioned stimulus is repeatedly presented without the aversive outcome until fear is no longer expressed3. This inhibitory learning creates a new, safe representation for the CS, which competes for expression with the original fear memory4. Although extinction is effective at inhibiting fear, it is not permanent. Fear can spontaneously recover with the passage of time. Exposure to stress or returning to the context of initial learning can also cause fear to resurface3,4.
Our protocol addresses the transient nature of extinction by targeting the reconsolidation window to modify emotional memory in a more permanent manner. Ample evidence suggests that reactivating a consolidated memory returns it to a labile state, during which the memory is again susceptible to interference5-9. This window of opportunity appears to open shortly after reactivation and close approximately 6hrs later5,11,16, although this may vary depending on the strength and age of the memory15. By allowing new information to incorporate into the original memory trace, this memory may be updated as it reconsolidates10,11. Studies involving non-human animals have successfully blocked the expression of fear memory by introducing pharmacological manipulations within the reconsolidation window, however, most agents used are either toxic to humans or show equivocal effects when used in human studies12-14. Our protocol addresses these challenges by offering an effective, yet non-invasive, behavioral manipulation that is safe for humans.
By prompting fear memory retrieval prior to extinction, we essentially trigger the reconsolidation process, allowing new safety information (i.e., extinction) to be incorporated while the fear memory is still susceptible to interference. A recent study employing this behavioral manipulation in rats has successfully blocked fear memory using these temporal parameters11. Additional studies in humans have demonstrated that introducing new information after the retrieval of previously consolidated motor16, episodic17, or declarative18 memories leads to interference with the original memory trace14. We outline below a novel protocol used to block fear recovery in humans.

Conditioned fear can be diminished through an inhibitory process called extinction, but can resurface under conditions such as the passage of time or exposure to stress. Our protocol presents a novel way of preventing fear recovery by introducing extinction during the reconsolidation window (the re-storage phase of a reactivated memory).

Fear is maladaptive when it persists long after circumstances have become safe. It is therefore crucial to develop an approach that persistently prevents ...

Assessment of Mouse Judgment Bias through an Olfactory Digging Task

Judgment biases (JB) are differences in the way that individuals in positive and negative affective/emotional states interpret ambiguous information. This phenomenon has long been observed in humans, with individuals in positive states responding to ambiguity 'optimistically' and those in negative states instead showing 'pessimism'. Researchers aiming to assess animal affect have taken advantage of these differential responses, developing tasks to assess judgment bias as an indicator of affective state. These tasks are becoming increasingly popular across diverse species and fields of research. However, for laboratory mice, the most widely used vertebrates in research and a species heavily relied upon to model affective disorders, only one JB task has been successfully validated as sensitive to changes in affective state. Here, we provide a detailed description of this novel murine JB task, and evidence of its sensitivity to mouse affect. Though refinements are still necessary, assessment of mouse JB opens the door for answering both practical questions regarding mouse welfare, and fundamental questions about the impact of affective state in translational research.

This article provides a detailed description of a novel mouse judgment bias protocol. Evidence of this olfactory digging task's sensitivity to affective state is also demonstrated and its utility across diverse research fields is discussed.

Judgment biases (JB) are differences in the way that individuals in positive and negative affective/emotional states interpret ambiguous information. This ...

Threat-Safety Test for Stress Susceptibility or Resilience in Mice Models

Social Threat-Safety Test Uncovers Psychosocial Stress-Related Phenotypes

Social stress is a major cause of the development of mental disorders. To enhance the translational value of preclinical studies, social stress experience and its behavioral impact on mice should be comparable to humans. Chronic social defeat (CSD) utilizes a type of social stress involving physical attacks and sensory threats to induce mental dysfunctions resembling human affective disorders. To strengthen the psychosocial component of CSD, a 10-day CSD protocol was applied in which daily physical attacks are standardized to three 10 s episodes followed by a 24 h sensory phase. After the 10th sensory phase, the CSD protocol is followed by a refined behavioral assay called the social threat-safety test (STST). Post-stress behavioral assays need to determine how and to what extent the social stressor has influenced behavior. The STST allows chronically socially defeated male mice to interact with 2 novel male individuals (social targets): one social target from the attacking strain encountered during the CSD days and the other from a novel strain. Both are presented simultaneously in different compartments of a three-chambered test arena. The test enables a simultaneous assessment of social avoidance development to measure successful aversive conditioned learning and social threat-safety discrimination ability. The development of social avoidance towards both strains reflects a generalized aversive response and thus, a measurement of stress susceptibility. Meanwhile, the development of social avoidance towards only the attacking strain reflects threat-safety discrimination and thus, a measurement of stress resilience. Finally, the absence of social avoidance towards the attacking strain reflects impaired aversive conditioned learning. The protocol aims to refine the currently used mouse models of stress susceptibility/resilience by including translational criteria, specifically threat-safety discrimination and aversive response generalization, to categorize a single group of chronically socially defeated animals into resilient and susceptible subgroups, eventually advancing future translational approaches.

Author Spotlight: Unveiling Mechanisms of Stress Resilience - Significant Findings, Advancements, and Future Research

The social threat-safety test allows a simultaneous assessment of social avoidance development as a measurement of aversive conditioned learning and social threat-safety discrimination ability, both utilized to identify stress-susceptible and stress-resilient individuals within a single group of chronically socially defeated male mice.

Social stress is a major cause of the development of mental disorders. To enhance the translational value of preclinical studies, social stress experience ...