Biol Psychiatry Cogn Neurosci Neuroimaging
November 2024
Background: The Reward Positivity (RewP) is a sensitive and specific electrophysiological marker of reward receipt. These characteristics make it a compelling candidate marker of dysfunctional reward processing in Major Depressive Disorder (MDD). We previously proposed that the RewP is a temporal nexus for multiple dimensions of reward value, and that a diminished RewP in depression might only reflect a deficit in some of these features.
View Article and Find Full Text PDFThis scientific commentary refers to ‘Direct current stimulation modulates prefrontal cell activity and behaviour without inducing seizure-like firing’ by Fehring (https://doi.org/10.1093/brain/awae273).
View Article and Find Full Text PDFDepression is a common consequence of traumatic brain injury. Separately, spontaneous depression-arising without brain injury-has been linked to abnormal responses in motivational neural circuitry to the anticipation or receipt of rewards. It is unknown if post-injury and spontaneously occurring depression share similar phenotypic profiles.
View Article and Find Full Text PDFModerate prenatal alcohol exposure (mPAE) results in structural alterations to the hippocampus. Previous studies have reported impairments in hippocampal-sensitive tasks, but have not compared performance between male and female animals. In the present study, performance in hippocampal-sensitive spatial memory and anxiety behavior tests were compared across adult male and female saccharin (SACC) control mPAE Long-Evans rat offspring.
View Article and Find Full Text PDFBackground: Hazardous drinking is associated with maladaptive alcohol-related decision-making. Existing studies have often focused on how participants learn to exploit familiar cues based on prior reinforcement, but little is known about the mechanisms that drive hazardous drinkers to explore novel alcohol cues when their value is not known.
Methods: We investigated exploration of novel alcohol and non-alcohol cues in hazardous drinkers (N = 27) and control participants (N = 26) during electroencephalography (EEG).
Background: The Reward Positivity (RewP) is sensitive and specific electrophysiological marker of reward receipt. These characteristics make it a compelling candidate marker of dysfunctional reward processing in major depressive disorder. We previously proposed that the RewP is a nexus of multiple aspects of reward variance, and that a diminished RewP in depression might only reflect a deficit in some of this variance.
View Article and Find Full Text PDFThoughts and actions are often driven by a decision to either explore new avenues with unknown outcomes, or to exploit known options with predictable outcomes. Yet, the neural mechanisms underlying this exploration-exploitation trade-off in humans remain poorly understood. This is attributable to variability in the operationalization of exploration and exploitation as psychological constructs, as well as the heterogeneity of experimental protocols and paradigms used to study these choice behaviours.
View Article and Find Full Text PDFDynamic changes in neurodevelopment and cognitive functioning occur during adolescence, including a switch from reactive to more proactive forms of cognitive control, including response inhibition. Pediatric mild traumatic brain injury (pmTBI) affects these cognitions immediately post-injury, but the role of vascular versus neural injury in cognitive dysfunction remains debated. This study consecutively recruited 214 sub-acute pmTBI (8-18 years) and age/sex-matched healthy controls (HC; N = 186), with high retention rates (>80%) at four months post-injury.
View Article and Find Full Text PDFPsychiatry Res Neuroimaging
September 2023
The Reward Positivity (RewP) is an event-related potential component with a delta band spectral representation that is elicited by reward receipt. Evidence suggests that RewP is modulated by both reward probability as well as affective valuation ("liking"). Here we determined whether RewP is a marker of enhanced hedonic salience of alcohol images in hazardous drinkers.
View Article and Find Full Text PDFUnderstanding the unique functions of different subregions of primate prefrontal cortex has been a longstanding goal in cognitive neuroscience. Yet, the anatomy and function of one of its largest subregions (the frontopolar cortex) remain enigmatic and underspecified. Our Society for Neuroscience minisymposium will comprise a range of new anatomic and functional approaches that have helped to clarify the basic circuit anatomy of the frontal pole, its functional involvement during performance of cognitively demanding behavioral paradigms in monkeys and humans, and its clinical potential as a target for noninvasive brain stimulation in patients with brain disorders.
View Article and Find Full Text PDFFlexible decision-making requires animals to forego immediate rewards (exploitation) and try novel choice options (exploration) to discover if they are preferable to familiar alternatives. Using the same task and a partially observable Markov decision process (POMDP) model to quantify the value of choices, we first determined that the computational basis for managing explore-exploit tradeoffs is conserved across monkeys and humans. We then used fMRI to identify where in the human brain the immediate value of exploitative choices and relative uncertainty about the value of exploratory choices were encoded.
View Article and Find Full Text PDFHumans are highly adept at differentiating, regulating, and responding to their emotions. At the core of all these functions is emotional awareness: the conscious feeling states that are central to human mental life. Disrupted emotional awareness-a subclinical construct commonly referred to as alexithymia-is present in a range of psychiatric and neurological disorders and can have a deleterious impact on functional outcomes and treatment response.
View Article and Find Full Text PDFApathy is a common and impairing sequela of traumatic brain injury (TBI). Yet, little is known about the neural mechanisms determining in which patients apathy does or does not develop post-TBI. We aimed to elucidate the impact of TBI on motivational neural circuits and how this shapes apathy over the course of TBI recovery.
View Article and Find Full Text PDFBiol Psychiatry Cogn Neurosci Neuroimaging
August 2021
Background: It remains unclear whether executive control (EC) deficits in autism spectrum disorder (ASD) represent a failure in proactive EC (engaged and maintained before a cognitively demanding event) or in reactive EC (engaged transiently as the event occurs). We addressed this question by administering a paradigm investigating components of EC in a sample of individuals with ASD and typically developing individuals during functional magnetic resonance imaging.
Methods: During functional magnetic resonance imaging, 141 participants (64 ASD, 77 typically developing) completed a rapid preparing to overcome prepotency task that required participants to respond to an arrow probe based on the color of an initially presented cue.
Background: Functional underpinnings of cognitive control deficits in unbiased samples (i.e., all comers) of patients with psychotic spectrum disorders (PSD) remain actively debated.
View Article and Find Full Text PDFImplementing motivated behaviors on the basis of prior reward is central to adaptive human functioning, but aberrant reward-motivated behavior is a core feature of neuropsychiatric illness. Children from disadvantaged neighborhoods have decreased access to rewards, which may shape motivational neurocircuits and risk for psychopathology. Here, we leveraged the unprecedented neuroimaging data from the Adolescent Brain Cognitive Development (ABCD) study to test the hypothesis that neighborhood socioeconomic disadvantage shapes the functional recruitment of motivational neurocircuits in children.
View Article and Find Full Text PDFSensorimotor synchronization (SMS) is frequently dependent on coordination of excitatory and inhibitory activity across hemispheres, as well as the cognitive control over environmental distractors. However, the timing (motor planning versus execution) and cortical regions involved in these processes remain actively debated. Functional magnetic resonance imaging data were therefore analyzed from 34 strongly right-handed healthy adults performing a cued (to initiate motor planning) SMS task with either their right or left hand (motor execution phase) based on spatially congruent or incongruent visual stimuli.
View Article and Find Full Text PDFData analysis workflows in many scientific domains have become increasingly complex and flexible. Here we assess the effect of this flexibility on the results of functional magnetic resonance imaging by asking 70 independent teams to analyse the same dataset, testing the same 9 ex-ante hypotheses. The flexibility of analytical approaches is exemplified by the fact that no two teams chose identical workflows to analyse the data.
View Article and Find Full Text PDFAlthough autism spectrum disorder (ASD) is characterized by deficits in cognitive control, our previous work has shown that preparatory, goal-directed cognitive processing (proactive control) may be preserved in children with ASD. We investigated whether proactive control is intact in adolescents and young adults with ASD, as well as how symptoms of ASD (repetitive behaviors) and psychopathology (Depressive, Anxiety, and Attention-Deficit/Hyperactivity Problems) are related to proactive control. Participants were adolescents and young adults with ASD ( = 44) and typical development (TD; = 44).
View Article and Find Full Text PDFResearch has observed evidence for both hypo-(supposedly due to a broken mirror neuron system) and hyper-(thought to be the result of deficits in adaptive control) imitation in autism spectrum disorder (ASD). This work sought to adjudicate between these findings using an automatic imitation (AI) paradigm with the novel manipulation of the need to engage adaptive control of imitation. Results demonstrated that ASD participants do not display a specific deficit in AI capability, are able to engage in proactive control of AI, and that relative to a well-matched effector condition, AI is not selectively associated with ASD symptom severity.
View Article and Find Full Text PDFBiol Psychiatry Cogn Neurosci Neuroimaging
January 2020
Background: The degree to which individuals with autism spectrum disorder (ASD) evidence impairments in episodic memory relative to their typically developing (TD) counterparts remains unclear. According to a prominent view, ASD is associated with deficits in encoding associations between items and recollecting precise context details. Here, we evaluated behavioral and neural evidence for this impaired relational binding hypothesis using a task involving relational encoding and recollection during functional magnetic resonance imaging.
View Article and Find Full Text PDFHumans compute the anticipated reward value of stimuli in their environment in order to behave in an adaptive, goal-directed manner. This reward valuation ability is vital, and its disruption in a range of clinical populations has profound personal and social consequences. However, research has often failed to consider the reward-related functions of a central component of human emotion: conscious emotional experience.
View Article and Find Full Text PDFProactive control refers to the active representation of contextual information to bias cognitive processing and facilitate goal-directed behavior. Despite research suggesting that proactive control may be impaired in autism spectrum disorder (ASD), the associations between proactive control and clinical symptoms of ASD remain underspecified. Here, we combined a children's version of the AX Continuous Performance Task (AX-CPT) with gold standard clinical assessments in children with ASD (N = 34) or typical development (TYP; N = 45).
View Article and Find Full Text PDFBackground: Internalizing symptoms like anxiety and depression are common and impairing in autism spectrum disorder (ASD). Here, we test the hypothesis that aberrant functional connectivity among three brain networks (salience network [SN], default mode network [DMN], and frontoparietal network [FPN]) plays a role in the pathophysiology of internalizing in ASD.
Methods: We examined the association between resting-state functional connectivity and internalizing in 102 adolescents and young adults with ASD (n = 49) or typical development (n = 53).