Behavior and Behavior Mechanisms Commons^™

The Effects Of Selected Drugs On The Memory Recall Of Sleep Deprived Mice, Jenn Pauldurai

Capstone Research Projects

Humans often make use of the neurotransmission altering effects of drugs such as caffeine, ephedrine, and ethanol. These drugs induce changes in memory and learning ability, specifically when used for sleep deprivation. English white mice (Mus musculus) have been shown to exhibit similar cognitive changes when administered drugs while sleep deprived. A sample of 20 mice was divided into three experimental groups (each group receiving a different drug) and one control group. Maze-testing demonstrated that mice performance decreased with sleep deprivation (Treatment-1) but all groups returned to baseline performance when injected (IP) with selected drugs (Treatment-2), regardless of …

Concordance Of Meg And Fmri Patterns In Adolescents During Verb Generation, Yingying Wang, Scott K. Holland, Jennifer Vannest

Center for Brain, Biology, and Behavior: Faculty Publications

In this study we focused on direct comparison between the spatial distributions of activation detected by functional magnetic resonance imaging (fMRI) and localization of sources detected by magnetoencephalography (MEG) during identical language tasks. We examined the spatial concordance between MEG and fMRI results in 16 adolescents performing a three-phase verb generation task that involves repeating the auditorily presented concrete noun and generating verbs either overtly or covertly in response to the auditorily presented noun. MEG analysis was completed using a synthetic aperture magnetometry (SAM) technique, while the fMRI data were analyzed using the general linear model approach with random-effects. To …

Norepinephrine Involvement In The Intermittent Swim Stress-Induced Deficit In Spatial Learning And Memory, Emily Elgert

Honors Theses and Capstones

Learning and memory impairments are often caused by stress disorders including depression. The present study investigated the involvement of norepinephrine in the swim stress-induced deficits of spatial learning and memory. Exposure to intermittent swim stress (ISS) followed by learning and memory tests in the Morris water maze (MWM) were used to investigate this relationship. The ISS paradigm consists of intermittent exposure to cold water, producing stress responses in rats. Reboxetine, a norepinephrine selective reuptake inhibitor (NSRI), was employed to investigate whether this compound reverses the ISS-induced deficit. In other words, rats exposed to the ISS, were hypothesized to experience impaired …

A One-Hour Sleep Restriction Impacts Brain Processing In Young Children Across Tasks: Evidence From Event-Related Potentials, Dennis Molfese, Anna Ivanenko, Alexandra P.F. Key, Adrienne Roman, Victoria J. Molfese, Louise M. O'Brien, David Gozal, Srinivas Kota, Caitlin M. Hudac

Center for Brain, Biology, and Behavior: Faculty Publications

The effect of mild sleep restriction on cognitive functioning in young children is unclear, yet sleep loss may impact children's abilities to attend to tasks with high processing demands. In a preliminary investigation, six children (6.6 - 8.3 years of age) with normal sleep patterns performed three tasks: attention (“Oddball”), speech perception (conconant-vowel syllables) and executive function (Directional Stroop). Event-related potentials (ERP) responses were recorded before (Control) and following one-week of 1-hour per day of sleep restriction. Brain activity across all tasks following Sleep Restriction differed from activity during Control Sleep, indicating that minor sleep restriction impacts children's neurocognitive functioning.

Normative Topographic Erp Analyses Of Speed Of Speech Processing And Grammar Before And After Grammatical Treatment, Paul J. Yoder, Dennis Molfese, Micah M. Murray, Alexandra P.F. Key

Center for Brain, Biology, and Behavior: Faculty Publications

Typically developing (TD) preschoolers and age-matched preschoolers with specific language impairment (SLI) received event-related potentials (ERPs) to four monosyllabic speech sounds prior to treatment and, in the SLI group, after 6 months of grammatical treatment. Before treatment, the TD group processed speech sounds faster than the SLI group. The SLI group increased the speed of their speech processing after treatment. Post-treatment speed of speech processing predicted later impairment in comprehending phrase elaboration in the SLI group. During the treatment phase, change in speed of speech processing predicted growth rate of grammar in the SLI group.

The Effect Of Visual Wulst Lesions And Trigeminal Nerve Sectioning On The Discrimination Of Magnetic Inclination In The Homing Pigeon (Columba Livia), Merissa Acerbi

Honors Projects

The ability of homing pigeons to return to their loft from unknown places has fascinated scientists for centuries. It is well established that homing pigeons, like migratory birds, posses an innate magnetic inclination compass to determine direction by measuring the angle between the magnetic field vector and the Earth's surface. Recent work has indicated that the avian magnetic compass is light mediated and appears to mediate magnetic information to the brain. This occurs via a visual pathway with processing in the visual Wulst area of the forebrain. There is, however, also evidence from other avian species that magnetic direction may …

Methylphenidate And Atomoxetine Treatment During Adolescence In The Spontaneously Hypertensive Rat: Mechanisms Underlying High Cocaine Abuse Liability In Attention Deficit/Hyperactivity Disorder, Sucharita S. Somkuwar

Theses and Dissertations--Pharmacy

Effects of pharmacotherapies for Attention Deficit/Hyperactivity Disorder (ADHD) on cocaine abuse liability in ADHD are not understood. Spontaneously Hypertensive Rats (SHR), an ADHD model, exhibited greater cocaine self-administration than control Wistar-Kyoto and Wistar rats. Methylphenidate, but not atomoxetine during adolescence enhanced cocaine self-administration in adult SHRs compared to controls. The mesocortical dopaminergic system, including medial prefrontal (mPFC) and orbitofrontal (OFC) cortices, is important for ADHD and cocaine addiction. Dopamine and norepinephrine transporter (DAT and NET) are molecular targets for methylphenidate, atomoxetine and cocaine action.

In the current studies, SHR, Wistar-Kyoto and Wistar were administered methylphenidate (1.5 mg/kg/day, p.o.), atomoxetine (0.3 …

Rats Acquire Stronger Preference For Flavors Consumed Towards The End Of A High-Fat Meal, Kevin P. Myers

Faculty Journal Articles

Rats learn to prefer flavors associated with postingestive effects of nutrients. The physiological signals underlying this postingestive reward are unknown. We have previously shown that rats readily learn to prefer a flavor that was consumed early in a multi-flavored meal when glucose is infused intragastrically (IG), suggesting rapid postingestive reward onset. The present experiments investigate the timing of postingestive fat reward, by providing distinctive flavors in the first and second halves of meals accompanied by IG fat infusion. Learning stronger preference for the earlier or later flavor would indicate when the rewarding postingestive effects are sensed. Rats consumed sweetened, calorically-dilute …

Autonomic And Behavioral Reactivity To An Acute Laboratory Stressor, Jeremy C. Peres

LSU New Orleans Theses and Dissertations

Stress has been widely shown to directly influence people’s emotional and behavioral processing as well as their underlying biological systems. This project examined physiological and behavioral responses as indicators of stress and coping in the context of a psychosocial stressor in a controlled laboratory setting. We examined the association between indicators of behavioral coping and underlying physiological reactivity within participants while experiencing stress. Participants included 68 emerging adults. Physiological measures include autonomic biomarkers (e.g., heart-rate, skin conductance) at rest and during the stressor while behavioral indicators that were coded include acute verbal and non-verbal actions exhibited by participants during the …

Septohippocampal Gabaergic Neurons Mediate The Altered Behaviors Induced By N-Methyl-D-Aspartate Receptor Antagonists., Jingyi Ma, Siew Kian Tai, L Stan Leung

Physiology and Pharmacology Publications

We hypothesize that selective lesion of the septohippocampal GABAergic neurons suppresses the altered behaviors induced by an N-methyl-D-aspartate (NMDA) receptor antagonist, ketamine or MK-801. In addition, we hypothesize that septohippocampal GABAergic neurons generate an atropine-resistant theta rhythm that coexists with an atropine-sensitive theta rhythm in the hippocampus. Infusion of orexin-saporin (ore-SAP) into the medial septal area decreased parvalbumin-immunoreactive (GABAergic) neurons by ~80%, without significantly affecting choline-acetyltransferase-immunoreactive (cholinergic) neurons. The theta rhythm during walking, or the immobility-associated theta induced by pilocarpine, was not different between ore-SAP and sham-lesion rats. Walking theta was, however, more disrupted by atropine sulfate in ore-SAP than …

Sleep Hygiene And Problem Behaviors In Snoring And Non- Snoring School-Age Children, Lisa A. Witcher, David Gozal, Dennis L. Molfese, Scott M. Salathe, Karen Spruyt, Valerie Mclaughlin Crabtree

Center for Brain, Biology, and Behavior: Faculty Publications

Objectives—The effects of sleep-disordered breathing, sleep restriction, dyssomnias, and parasomnias on daytime behavior in children have been previously assessed. However, the potential relationship(s) between sleep hygiene and children’s daytime behavior remain to be explored. The primary goal of this study was to investigate the relationship between sleep hygiene and problematic behaviors in non-snoring and habitually snoring children.

Methods—Parents of 100 5- to 8-year-old children who were reported to snore “frequently” to “almost always,” and of 71 age-, gender-, and ethnicity-matched children who were reported to never snore participated in this study. As part of a larger, ongoing study, …

Cognitive Effects Of One Season Of Head Impacts In A Cohort Of Collegiate Contact Sport Athletes, Thomas W. Mcallister,, Laura A. Flashman, Arthur C. Maerlender, Richard M. Greenwald, Jonathan G. Beckwith, Tor D. Tosteson, Joe Crisco, Per Gunner Brolinson, Stefan Duma, Ann-Christine Duhaime, M. R. Grove, John H. Turco

Center for Brain, Biology, and Behavior: Faculty Publications

Objective: To determine whether exposure to repetitive head impacts over a single season negatively affects cognitive performance in collegiate contact sport athletes.

Methods: This is a prospective cohort study at 3 Division I National Collegiate Athletic Association athletic programs. Participants were 214 Division I college varsity football and ice hockey players who wore instrumented helmets that recorded the acceleration-time history of the head following impact, and 45 noncontact sport athletes. All athletes were assessed prior to and shortly after the season with a cognitive screening battery (ImPACT) and a subgroup of athletes also were assessed with 7 measures from a …

Initial Mlu Predicts The Relative Efficacy Of Two Grammatical Treatments In Preschoolers With Specific Language Impairments, Paul J. Yoder, Dennis L. Molfese, Elizabeth Gardner

Center for Brain, Biology, and Behavior: Faculty Publications

Purpose—We sought to confirm predictions based on past findings that pre-treatment mean length of utterance (MLU) would predict which of two grammatical treatments would best facilitate generalized and maintained grammatical development in preschoolers with specific language impairment (SLI).

Method—The participants were 57 preschoolers with specific language impairment (SLI). A randomized group experiment was used. The two grammatical treatments were Broad Target Recasts (BTR) and Milieu Language Teaching (MLT). MLU was assessed at Time 1 in two conversational language samples. Growth rate of productive grammar was quantified using growth curve modeling on the Index of Productive Syntax (IPSyn) from …

Interictal Magnetoencephalographic Findings Related With Surgical Outcomes In Lesional And Nonlesional Neocortical Epilepsy, Rui Zhang, Ting Wu, Yingying Wang, Hongyi Liu, Yuanjie Zou, Wen Liu, Jing Xiang, Chaoyong Xiao, Lu Yang, Zhen Fu

Center for Brain, Biology, and Behavior: Faculty Publications

Purpose: To investigate whether interictal magnetoencephalography (MEG) concordant with other techniques can predict surgical outcome in patients with lesional and nonlesional refractory neocortical epilepsy (NE).

Methods: 23 Patients with lesional NE and 20 patients with nonlesional NE were studied. MEG was recorded for all patients with a 275 channel whole-head system. Synthetic aperture magnetometry (SAM) with excess kurtosis (g2) and conventional Equivalent Current Dipole (ECD) were used for MEG data analysis. 27 Patients underwent long-term extraoperative intracranial video electroencephalography (iVEEG) monitoring. Surgical outcomes were assessed based on more than 1-year of post-surgical follow-up using Engel classification system.

Results: As we …

Neuromagnetic Measures Of Word Processing In Bilinguals And Monolinguals, Yingying Wang, Jing Xiang, Jennifer Vannest, Tom Holroyd, Daria Narmoneva, Paul Horn, Yinhong Liu, Douglas Rose, Ton Degrauw, Scott Holland

Center for Brain, Biology, and Behavior: Faculty Publications

Objective: This study aimed to use magnetoencephalography (MEG) to examine the question of whether Mandarin-English bilingual speakers recruit the same cortical areas or develop distinct language-specific networks without overlaps for word processing.

Methods: Eight healthy Mandarin-English bilingual adults and eight healthy English monolingual adults were scanned while single-word paradigms were audio-visually presented.

Results: Our results showed significantly stronger beta-band power suppression in the right inferior parietal lobe (IPL) covering the supramarginal gyrus (BA 40) and angular gyrus (BA 39) for bilinguals when processing Mandarin versus English. Moreover, there were no significant differences between bilinguals and monolinguals in the left inferior …

Sleep Assessments In Healthy School-Aged Children Using Actigraphy: Concordance With Polysomnography, Karen Spruyt, David Gozal, Ehab Dayyat, Adrienne Roman, Dennis L. Molfese

Center for Brain, Biology, and Behavior: Faculty Publications

Actigraphic recordings (ACT) are widely used in school children as a less intrusive and more extended approach to evaluation of sleep problems. However, critical assessment of the validity and reliability of ACT against overnight polysomnography (NPSG) are unavailable. Thus, we explored the degree of concordance between NPSG and ACT in school-aged children to delineate potential ACT boundaries when interpreting pediatric sleep. Non-dominant wrist ACT was simultaneously recorded with NPSG in 149 healthy school-aged children (4.1 to 8.8 years old, 41.7% boys and 80.4% Caucasian) recruited from the community. Analyses were limited to the Actiware (MiniMitter-64) calculated parameters originating from 1-min …

Sleep Duration, Sleep Regularity, Body Weight, And Metabolic Homeostasis In School-Aged Children, Karen Spruyt, Dennis L. Molfese, David Gozal

Center for Brain, Biology, and Behavior: Faculty Publications

OBJECTIVE: The goal was to explore the effects of duration and regularity of sleep schedules on BMI and the impact on metabolic regulation in children.

METHODS: Sleep patterns of 308 community-recruited children 4 to 10 years of age were assessed with wrist actigraphs for 1 week in a cross-sectional study, along with BMI assessment. Fasting morning plasma levels of glucose, insulin, lipids, and high-sensitivity C-reactive protein also were measured for a subsample.

RESULTS: Children slept 8 hours per night, on average, regardless of their weight categorization. A nonlinear trend between sleep and weight emerged. For obese children, …

Sleep Estimates In Children: Parental Versus Actigraphic Assessments, Ehab A. Dayyat, Karen Spruyt, Dennis L. Molfese, David Gozal

Center for Brain, Biology, and Behavior: Faculty Publications

Background: In the context of increasing awareness about the need for assessment of sleep duration in community and clinical settings, the use of questionnaire-based tools may be fraught with reporter bias. Conversely, actigraphy provides objective assessments of sleep patterns. In this study, we aimed to determine the potential discrepancies between parentally-based sleep logs and concurrent actigraphic recordings in children over a one-week period.

Methods: We studied 327 children aged 3–10 years, and included otherwise healthy, nonsnoring children from the community who were reported by their parents to be nonsnorers and had normal polysomnography, habitually-snoring children from the community …

Minimal Information For Neural Electromagnetic Ontologies (Minemo): A Standards-Compliant Method For Analysis And Integration Of Event-Related Potentials (Erp) Data, Gwen Frishkoff, Jason Sydes, Kurt Mueller, Tim Curran, John F. Connolly, Kerry Kilborn, Dennis L. Molfese, Charles Perfetti, Allen D. Malony

Center for Brain, Biology, and Behavior: Faculty Publications

We present MINEMO (Minimal Information for Neural ElectroMagnetic Ontologies), a checklist for the description of event-related potentials (ERP) studies. MINEMO extends MINI (Minimal Information for Neuroscience Investigations)to the ERP domain. Checklist terms are explicated in NEMO, a formal ontology that is designed to support ERP data sharing and integration. MINEMO is also linked to an ERP database and web application (the NEMO portal). Users upload their data and enter MINEMO information through the portal. The database then stores these entries in RDF (Resource Description Framework), along with summary metrics, i.e., spatial and temporal metadata. Together these spatial, temporal, and functional …

Orbitofrontal Cortex Provides Cross-Modal Valuation Of Self-Generated Stimuli, William A. Cunningham, Ingrid J. Haas, Ashley S. Waggoner

Department of Political Science: Faculty Publications

Prior research has shown that the orbitofrontal cortex (OFC) plays an important role in the representation of the evaluation of stimuli, regardless of stimulus modality. Based on these findings, researchers have proposed that the OFC serves a common currency function, allowing for the direct comparison of different types of perceptual stimuli (e.g. food, drink, money). The present study was designed to extend this research and investigate whether these same regions of OFC that have been identified in previous research are involved in evaluating imagined stimuli. Specifically, we asked participants to draw on prior attitudinal knowledge to generate internal representations of …

Motivational Profiles And Their Associations With Achievement Outcomes, Bo Shen, Nate Mccaughtry, Jeffrey J. Martin, Mariane Fahlman

Kinesiology, Health and Sport Studies

With the belief that theoretical integration in motivation may help us better understand motivational behavior, we designed this study to explore adolescents’ motivational profiles and their associations with knowledge acquisition, leisure-time exercise behaviors, and cardiorespiratory fitness. Middle school students from a large urban inner-city school district (N = 603, ages 12–14) completed questionnaires assessing motivational constructs and leisure-time exercise behavior. Knowledge and cardiorespiratory fitness were also assessed with a knowledge test and the Progressive Aerobic Cardiovascular Endurance Run (PACER) test, respectively. Using hierarchical cluster analysis, we found that students’ motivation in physical education could be explained from a multi-theoretical …

Sleep-Disordered Breathing Affects Auditory Processing In 5–7 Year-Old Children: Evidence From Brain Recordings, Alexandra P.F. Key, Dennis L. Molfese, Louise O’Brien, David Gozal

Center for Brain, Biology, and Behavior: Faculty Publications

Poor sleep in children is associated with lower neurocognitive functioning and increased maladaptive behaviors. The current study examined the impact of snoring (the most common manifestation of sleep-disordered breathing) on cognitive and brain functioning in a sample of 35 asymptomatic children ages 5–7 years identified in the community as having habitual snoring (SDB). All participants completed polysomnographic, neurocognitive (NEPSY) and psychophysiological (ERPs to speech sounds) assessments. The results indicated that sub-clinical levels of SDB may not necessarily lead to reduced performance on standardized behavioral measures of attention and memory. However, brain indices of speech perception and discrimination (N1/P2) are sensitive …

Cognitive Inference And Resulting Behaviors In Response To Ambiguous Threat In The Coyote, Canis Latrans, Sarah Shawnee Dawson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

While antipredator strategies have been a focus of behavioral research for decades, scientists generally study the responses of prey toward overt, explicit threat. However, risk can also be significant when a threat is covert, such as when an ambush predator may be nearby or a secondary threat remains after a predator's departure. Little is known about the mechanism that prey use to assess risk in a predator's absence. Tests were conducted to determine the manner in which coyotes respond to these ambiguous threats. Specifically, I tested whether coyotes respond to prior anthropogenic activity that has occurred near their only food …

Frequency And Spatial Characteristics Of Highfrequency Neuromagnetic Signals In Childhood Epilepsy, Jing Xiang, Yang Liu, Yingying Wang, Elijah G. Kirtman, Cincinnati Children’S Hospital Medical Center Kotecha, Yangmei Chen, Xiaolin Huo, Hisako Fujiwara, Nat Hemasilpin, Ki Lee, Francesco T. Mangano, James Leach, Blaise Jones, Ton Degrauw, Douglas Rose

Center for Brain, Biology, and Behavior: Faculty Publications

Purpose. Invasive intracranial recordings have suggested that high-frequency oscillation is involved in epileptogenesis and is highly localized to epileptogenic zones. The aim of the present study is to characterize the frequency and spatial patterns of high-frequency brain signals in childhood epilepsy using a non-invasive technology. Methods. Thirty children with clinically diagnosed epilepsy were studied using a whole head magnetoencephalography (MEG) system. MEG data were digitized at 4 000 Hz. The frequency and spatial characteristics of high-frequency neuromagnetic signals were analyzed using continuous wavelet transform and beamformer. Threedimensional magnetic resonance imaging (MRI) was obtained for each patient to localize magnetic sources. …

Impairments In Attention In Occasionally Snoring Children: An Event-Related Potential Study, Maria E. Barnes, Elizabeth A. Huss, Krista N. Garrod, Eric Van Raay, Ehab Dayyat, Dennis L. Molfese

Center for Brain, Biology, and Behavior: Faculty Publications

Objective—To determine whether minimal snoring is benign in children.

Procedure—22 rarely snoring children (mean age=6.9 years, 11 females) and age- and sexmatched controls participated in an auditory oddball task wearing 128-electrode nets. Parents completed Conner’s Parent Rating Scales-Revised Long (CPRS-R:L).

Results—Snorers scored significantly higher on 4 CPRS-R:L subscales. Stepwise regression indicated that two ERP variables from a region of the ERP that peaked at 844 ms post-stimulus onset predicted CPRS-R:L ADHD Index scores.

Conclusions—Occasional snorers according to parental report do exhibit ADHD-like behaviors. Basic sensory processing is longer than in controls, suggesting that delayed frontal activation requires more effort in …

A Study Of Possible Pre-Cognitive Advantages Of Bilingualism, Marisela Gutierrez

Open Access Theses & Dissertations

Past research has suggested that second language acquisition has a beneficial effect on the development of inhibitory control processes in children and adults. This has been referred to as the "bilingual advantage" and is most commonly quantified using the Simon task. Whether the bilingual advantage extends to precognitive mechanisms has not yet been examined. The goals of this study were to examine the bilingual advantage in university students; and to examine whether the bilingual advantage extends to the precognitive filtering mechanism of sensorimotor gating. It was predicted that, as compared to monolinguals, bilingual university students would have greater inhibitory control, …

Does Type Of Stimulus Influence Task-Irrelevant Evaluative Categorization Processes?, Guadalupe Corral

Open Access Theses & Dissertations

The effect of stimulus type on task-irrelevant evaluative categorization was examined in two separate studies by using the P3 component from event-related brain potentials. The first study presented idiosyncratic stimuli consisting of individuals that were rated by participants as either positive or negative within sequences of pictorial and verbal stimuli. The second study presented sequences of novel and familiar stimuli consisting of previously normed unattractive and neutral individuals. It was hypothesized that pictures would elicit task-irrelevant evaluative categorization processes and so would novel stimuli (relative to words and familiar stimuli, respectively). Task-irrelevance was examined by assessing P3 peak amplitude to …

Eye Movement, Rem Sleep And Adhd: An Examination Of Eye Movement Patterns During Rem Sleep In Adhd Populations, Elin Marie Grissom

All-Inclusive List of Electronic Theses and Dissertations

The current study investigates differences in patterns of eye movement and sleep architecture during REM stage sleep in children with a diagnosis of ADHD, compared to those without the diagnosis. Existing studies have found differences in eye movement patterns during waking hours in these two groups (Munoz, Armstrong, Hampton, & Moore, 2003; O'Laughlin, Brubaker, Gay, Deans, & Aaron, 2006) as well as differences in patterns of REM sleep. The current study will focus on the fine structure of eye movement in REM in children with and without ADHD. Using pediatric polysomnographic recordings, the frequency, density, strength, and inferred direction of …

Smoking During Pregnancy Affects Speech-Processing Ability In Newborn Infants, Alexandra P.F. Key, Melissa Ferguson, Dennis L. Molfese, Kelley Peach, Victoria J. Molfese

Center for Brain, Biology, and Behavior: Faculty Publications

BACKGROUND: Tobacco smoking during pregnancy is known to adversely affect development of the central nervous system in babies of smoking mothers by restricting utero–placental blood flow and the amount of oxygen available to the fetus. Behavioral data associate maternal smoking with lower verbal scores and poorer performance on specific language/auditory tests.

OBJECTIVES: In the current study we examined the effects of maternal smoking during pregnancy on newborns’ speech processing ability as measured by event-related potentials (ERPs).

METHOD: High-density ERPs were recorded within 48 hr of birth in healthy newborn infants of smoking (n = 8) and nonsmoking …

The Effect Of Handling Time On Temporal Discounting In Two New World Primates, Alexandra G. Rosati, Jeffrey R. Stevens, Marc D. Hauser

Center for Brain, Biology, and Behavior: Faculty Publications

Foraging decisions in nonhuman animals often require choosing between small, immediate food rewards and larger, more delayed rewards. Faced with such choices, animals typically discount or devalue the future quite strongly. Although discounting studies often focus on delays to reward access, other temporal intervals contribute to foraging rate, and thus may potentially influence discounting levels. Here, we examine the effect of handling time, the time required to process and consume food, on discounting in cottontop tamarins, Saguinus oedipus, and common marmosets, Callithrix jacchus, two species that differ in levels of temporal discounting. We presented subjects with a discounting task under …