Gabriel Dichter

• PhD
• Professor at University of North Carolina at Chapel Hill

Premenstrual dysphoric disorder (PMDD), a more severe manifestation of premenstrual syndrome (PMS), is characterized by emotional, behavioral, and physical symptoms that begin in the mid-to-late luteal phase of the menstrual cycle, when estradiol and progesterone levels precipitously decline, and remit after the onset of menses. Remotely monitoring...

The perimenopausal transition is marked by an increased risk for affective dysregulation and major depressive disorder (MDD), with hormone replacement therapy using estradiol (E2) showing promise for alleviating symptoms of perimenopausal-onset MDD (PO-MDD). Although E2's effectiveness is recognized, its mechanisms underlying mood symptom modulatio...

Purpose This study examined the impact of bilingualism on affective theory of mind (ToM) and social prioritization (SP) among autistic adults compared to neurotypical comparison participants. Method Fifty-two (25 autistic, 27 neurotypical) adult participants (ages 21–35 years) with varying second language (L2) experience, ranging from monolingual...

Background: Chronic stress alters reward sensitivity and contributes to the emergence of anhedonia. In clinical samples, the perception of stress is a strong predictor of anhedonia. While there is substantial evidence demonstrating psychotherapy reduces perceived stress, little is known regarding the effects of treatment-related decreases in perce...

Background Chronic stress alters reward sensitivity and contributes to the emergence of anhedonia. In clinical samples, the perception of stress is a strong predictor of anhedonia. While there is substantial evidence demonstrating psychotherapy reduces perceived stress, little is known regarding the effects of treatment-related decreases in perceiv...

In a transdiagnostic anhedonia sample, we found that recent stress and anhedonia severity are associated with reduced DA reward signaling in the left putamen. Relations between striatal DA release to reward and stress were evident across two stress measures (the PCL-5 and the PSS), but relations between striatal DA release to reward and anhedonia w...

Background : The neural mechanisms associated with anhedonia treatment response are poorly understood. Additionally, no study has investigated changes in resting-state functional connectivity (rsFC) accompanying psychosocial treatment for anhedonia. Methods : We evaluated a novel psychotherapy, Behavioral Activation Therapy for Anhedonia (BATA, n=...

This study confirms previous research indicating that physical difficulties and co-occurring mental health or other conditions are prevalent among adolescents identified with autism in early childhood (1-3,9). Approximately one in five had physical difficulties, and approximately three in five had additional mental health or other conditions, such...

To evaluate an eye tracking task as a predictor and outcome measure of treatment response for autism spectrum disorder (ASD) social skills interventions, adolescents and young adults with ASD completed the eye tracking task before, immediately after, and two months after completing Social Cognition and Interaction Training for Autism (SCIT-A). The...

The social motivation hypothesis of autism posits that autism spectrum disorder (ASD) is characterized by impaired motivation to seek out social experience early in life that interferes with the development of social functioning. This framework suggests that impaired mesolimbic dopamine function underlies compromised responses to social rewards in...

E-poster to be presented at the 59th Annual Meeting of ACNP. Using [11C]raclopride in conjunction with a reward processing task, we report evidence consistent with impaired striatal phasic DA release to rewards in ASD. We also found increased connectivity between the right putamen seed that demonstrated decreased DA release to incentives in the A...

Background: The social motivation hypothesis of autism suggests that autism spectrum disorder (ASD) is characterized by impaired motivation to seek out social experience early in life that interferes with the development of social functioning. This framework posits that impaired mesolimbic dopamine (DA) function underlies compromised responses to s...

Restricted interests (RIs) in autism spectrum disorder (ASD) are clinically impairing interests of unusual focus or intensity. They are a subtype of restricted and repetitive behaviors which are one of two diagnostic criteria for the disorder. Despite the near ubiquity of RIs in ASD, the neural basis for their development is not well understood. Ho...

A novel treatment for anhedonia increases sensitivity to reward.

Previous studies examining the neural substrates of reward processing in ASD have explored responses to rewards for oneself but not rewards earned for others (i.e., vicarious reward). This omission is notable given that vicarious reward processing is a critical component of creating and maintaining social relationships. The current study examined t...

Autism spectrum disorder (ASD) is characterized by impaired predictive abilities; however, the neural mechanisms subsuming reward prediction errors in ASD are poorly understood. In the current study, we investigated neural responses during social and nonsocial reward prediction errors in 22 adolescents with ASD (ages 12–17) and 20 typically develop...

Oxytocin (OT) is critical for the expression of social behavior across a wide array of species; however, the role of this system in the encoding of socially relevant information is not well understood. In the present study, we show that chemogenetic activation of OT neurons within the paraventricular nucleus of the hypothalamus (PVH) of male mice (...

Background: Fear of autism has led to a decline in childhood-immunization uptake and to a resurgence of preventable infectious diseases. Identifying characteristics of parents who believe in a causal role of vaccines for autism spectrum disorder (ASD) in their child may help targeting educational activities and improve adherence to the immunizatio...

Individuals with autism spectrum disorder (ASD) often meet criteria for at least one additional psychiatric disorder. The present study evaluated the utility of the Mini International Neuropsychiatric Interview (MINI) in assessing co-occurring psychiatric disorders in children, adolescents, and young adults with ASD. Ninety-one percent of children/...

This commentary highlights the observation that social motivation is usually an imprecisely specified construct. We suggest four social motivation conceptualizations across levels of analysis and explore where the target article situates among these. We then offer theoretical and practical guidance for operationalization and measurement of social m...

Few studies have explored neural mechanisms of reward learning in ASD despite evidence of behavioral impairments of predictive abilities in ASD. To investigate the neural correlates of reward prediction errors in ASD, 16 adults with ASD and 14 typically developing controls performed a prediction error task during fMRI scanning. Results revealed gre...

Background Mindfulness-Based Cognitive Therapy (MBCT) is an effective intervention for improving depressive symptoms, but the neural mechanisms associated with treatment response are unclear. Mindfulness strategies promoted in MBCT involve psychological processes supported by the Default Mode Network (DMN) such as present-moment awareness and non-j...

Background: Deficits in the ability to experience reward from natural, substance-free activities and stimuli is a common mechanism contributing to both opiate use disorder and depressive symptoms, and is a target of behavioral-focused treatments for substance use and depression. Although the neural response to monetary, positive affect-eliciting a...

Impaired predictive coding has been proposed as a framework to explain discrepancies between expectations and outcomes in autism spectrum disorder (ASD) that may contribute to core symptoms of the disorder. However, no eye tracking study has directly addressed this framework in the context of visual predictions of social and nonsocial stimuli. The...

Accumulating evidence suggests that autism spectrum disorder (ASD) may be conceptualized within a framework of reward processing impairments. The Social Motivation Theory of Autism posits that reduced motivation to interact with people and decreased pleasure derived from social interactions may derail typical social development and contribute to th...

Background: Although intranasal oxytocin (OXT) has been proposed to be a promising treatment for some psychiatric disorders, little research has addressed individual difference factors that may predict response to OXT. One such factor is early life abuse (ELA), which has widespread influences on social-emotional processing and behavior. This single...

Behavioral Activation (BA) is a contemporary third-wave psychosocial treatment approach that emphasizes helping individuals become more active in ways that are meaningful to them as a means of improving mood and quality of life. BA has been designated as a well-established, validated treatment for depression by the American Psychological Associatio...

Background: Neurobiological predictors of antidepressant response may help guide treatment selection and improve response rates to available treatments for major depressive disorder (MDD). Behavioral activation therapy for depression (BATD) is an evidence-based intervention designed to ameliorate core symptoms of MDD by promoting sustained engagem...

Social communication impairments have been a defining feature of autism spectrum disorder (ASD) since Leo Kanner’s seminal description of 11 children with idiosyncratic social behaviors.¹ In the 75 years since Kanner’s pivotal article, ASD research has focused on understanding and ameliorating the social communication and social cognitive impairmen...

Background: Intranasal oxytocin (OT) has been shown to improve social communication functioning of individuals with autism spectrum disorder (ASD) and, thus, has received considerable interest as a potential ASD therapeutic agent. Although preclinical research indicates that OT modulates the functional output of the mesocorticolimbic dopamine syst...

The Simons Foundation Autism Research Initiative (SFARI) has launched SPARKForAutism.org, a dynamic platform that is engaging thousands of individuals with autism spectrum disorder (ASD) and connecting them to researchers. By making all data accessible, SPARK seeks to increase our understanding of ASD and accelerate new supports and treatments for...

Background The objective of this study was to examine intrinsic whole-brain functional connectivity in ASD using the framework of functional segregation and integration. Emphasis was given to potential gender and developmental effects as well as identification of specific networks that may contribute to the global results. Methods We leveraged an...

This study investigated vicarious effort-based decision-making in 50 adolescents with autism spectrum disorders (ASD) compared to 32 controls using the Effort Expenditure for Rewards Task. Participants made choices to win money for themselves or for another person. When choosing for themselves, the ASD group exhibited relatively similar patterns of...

There are few reliable predictors of response to antidepressant treatments. In the present investigation we examined pretreatment functional brain connectivity during reward processing as a potential predictor of response to Behavioral Activation Therapy for Depression (BATD), a validated psychotherapy that promotes engagement with rewarding stimul...

We examined the late positive potential (LPP) event related potential in response to social and nonsocial stimuli from youths 9 to 19 years old with (n = 35) and without (n = 34) ASD. Social stimuli were faces with positive expressions and nonsocial stimuli were related to common restricted interests in ASD (e.g., electronics, vehicles, etc.). The...

Background: Experience sampling is a powerful method for obtaining ecologically valid data from research participants in real-world contexts. Given the urgent need for innovative and sensitive outcome measures in autism spectrum disorder (ASD) research, the present study sought to examine the feasibility of using experience sampling of positive af...

Prosaccade and antisaccade errors in the context of social and nonsocial stimuli were investigated in youth with autism spectrum disorder (ASD; n = 19) a matched control sample (n = 19), and a small sample of youth with obsessive compulsive disorder (n = 9). Groups did not differ in error rates in the prosaccade condition for any stimulus category....

Background: Impairments in social cognition are strongly associated with autism spectrum disorders (ASD). Moreover, the vast majority of individuals with autism demonstrate motivation toward Restricted Interests (RIs, e.g. computers). Neuroimaging has shown that areas of the brain along the lateral posterior cortex, which normally respond to static...

Major depressive disorder (MDD) is characterized by abnormal resting-state functional connectivity (RSFC), especially in medial prefrontal cortical (MPFC) regions of the default network. However, prior research in MDD has not examined dynamic changes in functional connectivity as networks form, interact, and dissolve over time. We compared unmedica...

Previous research has found accumulating evidence for atypical reward processing in autism spectrum disorders (ASD), particularly in the context of social rewards. Yet, this line of research has focused largely on positive social reinforcement, while little is known about the processing of negative reinforcement in individuals with ASD. The present...

An econometric choice task was used to estimate the implicit reward value of social and non-social stimuli related to restricted interests in children and adolescents with (n = 12) and without (n = 22) autism spectrum disorder (ASD). Mixed effects logistic regression analyses revealed that groups differed in valuation of images related to restricte...

Background Resting-state functional magnetic resonance imaging (fMRI) is a promising predictor of treatment response in major depressive disorder (MDD). Methods A search for papers published in English was conducted using PubMed with the following words: depression, treatment, resting-state, connectivity, and fMRI. Findings from 21 studies of rela...

Autism spectrum disorder (ASD) is characterized by high rates of comorbid internalizing and externalizing disorders. One mechanistic account of these comorbidities is that ASD is characterized by impaired emotion regulation (ER) that results in deficits modulating emotional responses. We assessed neural activation during cognitive reappraisal of fa...

Mood disorders are characterized by impaired emotion regulation abilities, reflected in alterations in frontolimbic brain functioning during regulation. However, little is known about differences in brain function when comparing regulatory strategies. Reappraisal and emotional acceptance are effective in downregulating negative affect, and are comp...

Despite the heterogeneous symptom presentation and complex etiology of Major Depressive Disorder (MDD), functional neuroimaging studies have shown with remarkable consistency that dysfunction in mesocorticolimbic brain systems are central to the disorder. Relatively less research has focused on the identification of biological markers of response t...

Anxiety is one of the most common clinical problems among children, adolescents, and adults with autism spectrum disorder (ASD), yet we know little about its etiology in the context of ASD. We posit that emotion regulation (ER) impairments are a risk factor for anxiety in ASD. Specifically, we propose that one reason why anxiety disorders are so fr...

This article suggests future directions for research aimed at improving our understanding of the etiology and pathophysiology of autism spectrum disorder (ASD) as well as pharmacologic and psychosocial interventions for ASD across the lifespan. The past few years have witnessed unprecedented transformations in the understanding of ASD neurobiology,...

Background: We should use precision when discussing social impairment, a cornerstone symptom domain of ASD. Currently, social affect generally is measured in terms of coarse global ratings based on distinct behaviors and summary impressions. Latent to this aggregate measurement, we hypothesize that there are independent though related dimensions, s...

The Sweet Taste Test (STT) is a standardized measure designed to index the ability to detect differences in sweet tastes (sweet taste sensitivity) and hedonic responses to sweet tastes (sweet taste liking). Profiles of response on the STT suggest enhanced hedonic responses to sweet tastes in psychiatric disorders characterized by dysfunctional rewa...

There has been significant progress in identifying genes that confer risk for autism spectrum disorders (ASDs). However, the heterogeneity of symptom presentation in ASDs impedes the detection of ASD risk genes. One approach to understanding genetic influences on ASD symptom expression is to evaluate relations between variants of ASD candidate gene...

This study investigated cognitive control of social and nonsocial information in autism using functional magnetic resonance imaging. Individuals with autism spectrum disorders (ASDs) and a neurotypical control group completed an oddball target detection task where target stimuli were either faces or nonsocial objects previously shown to be related...

Autism spectrum disorders (ASDs) and social anxiety disorder (SAD) are both characterized by social dysfunction, but no study to date has compared neural responses to social rewards in ASDs and SAD. Neural responses during social and non-social reward anticipation and outcomes were examined in individuals with ASD (n = 16), SAD (n = 15) and a contr...

Background Studies of individuals who do not meet criteria for major depressive disorder (MDD) but with subclinical levels of depressive symptoms may aid in the identification of neurofunctional abnormalities that possibly precede and predict the development of MDD. The purpose of this study was to evaluate relations between subclinical levels of d...

THIS REVIEW PRESENTS AN OVERVIEW OF FUNCTIONAL MAGNETIC RESONANCE IMAGING FINDINGS IN AUTISM SPECTRUM DISORDERS (ASDS), ALTHOUGH THERE IS CONSIDERABLE HETEROGENEITY WITH RESPECT TO RESULTS ACROSS STUDIES, COMMON THEMES HAVE EMERGED, INCLUDING: (i) hypoactivation in nodes of the "social brain" during social processing tasks, including regions within...

Individuals with autism spectrum disorders (ASD) demonstrate increased visual attention and elevated brain reward circuitry responses to images related to circumscribed interests (CI), suggesting that a heightened affective response to CI may underlie their disproportionate salience and reward value in ASD. To determine if individuals with ASD diff...

This thematic series presents theoretical and empirical papers focused on understanding autism from the perspective of reward processing deficits. Although the core symptoms of autism have not traditionally been conceptualized with respect to altered reward-based processes, it is clear that brain reward circuitry plays a critical role in guiding so...

This review summarizes evidence of dysregulated reward circuitry function in a range of neurodevelopmental and psychiatric disorders and genetic syndromes. First, the contribution of identifying a core mechanistic process across disparate disorders to disease classification is discussed, followed by a review of the neurobiology of reward circuitry....

Efficient effort expenditure to obtain rewards is critical for optimal goal-directed behavior and learning. Clinical observation suggests that individuals with autism spectrum disorders (ASD) may show dysregulated reward-based effort expenditure, but no behavioral study to date has assessed effort-based decision-making in ASD. The current study com...

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