Biology subjects

Hajcak, G.

Publications and source records attributed to Hajcak, G..

4 recordsLinked to original sources

bioRxiv2022

Disturbing standing balance evokes an error-related negativity

The error-related negativity (ERN) is a neural correlate of error monitoring often used to investigate individual differences in developmental, mental health, and adaptive contexts. However, limited experimental control over errors presents several confounds to its measurement. An experimentally controlled disturbance to standing balance evokes the balance N1, which we previously suggested may share underlying mechanisms with the ERN based on a number of shared features and factors. We now measure whether the balance N1 and ERN are correlated across individuals within two small groups (N=21 young adults and N=20 older adults). ERNs were measured in arrow flanker tasks using hand and foot response modalities (ERN-hand and ERN-foot). The balance N1 was evoked by sudden slip-like movements of the floor while standing. The ERNs and the balance N1 showed good and excellent internal consistency, respectively, and were correlated in amplitude in both groups. One principal component strongly loaded on all three evoked potentials, suggesting that the majority of individual differences are shared across the three ERPs. However, there remains a significant component of variance shared between the ERN-hand and ERN-foot beyond what they share with the balance N1. It is unclear whether this component of variance is specific to the arrow flanker task, or something fundamentally related to error processing that is not evoked by a sudden balance disturbance. If the balance N1 were to reflect error processing mechanisms indexed by the ERN, balance paradigms offer several advantages in terms of experimental control over errors.

neuroscience↗

bioRxiv2020

Blunted Neural Reward Responsiveness and Recent Suicidal Ideation in Children and Adolescents: Failure to Replicate Across Two Independent Samples

A recent study by Tsypes and colleagues (2019) found that children with recent suicidal ideation had blunted neural reward processing, as measured by the reward positivity (RewP), compared to matched controls, and that this difference was driven by reduced neural responses to monetary loss, rather than to reward. Here, we aimed to conceptually replicate and extend these findings in two samples (n = 264, 27 with suicidal ideation; and n = 314, 49 with suicidal ideation at baseline) of children and adolescents (11 to 15 years and 8 to 15 years, respectively). Results from both samples showed no evidence that children and adolescents with suicidal ideation have abnormal reward or loss processing, nor that reward processing predicts suicidal ideation two years later. The results highlight the need for greater statistical power, as well as continued research examining the neural underpinnings of suicidal thoughts and behaviors.

neuroscience↗

bioRxiv2020

Suicidal thoughts, behaviors, and event-related potentials: A meta-analysis

BackgroundSuicidal thoughts and behaviors (STBs) are thought to result from, at least in part, abnormalities in various neural systems. Event-related potentials (ERPs) are a useful method for studying neural activity and can be leveraged to study neural deficits related to STBs; however, it is unknown how effective ERPs are at differentiating various STB groups. The present meta-analysis examined how well ERPs can differentiate (a) those with and without suicidal ideation, (b) those with and without suicide attempts, (c) those with different levels of suicide risk, and (d) differences between those with suicide attempts versus those with suicidal ideation only. MethodThis meta-analysis included 208 effect sizes from 2,517 participants from 27 studies. We used a random-effects meta-analysis using a restricted maximum likelihood estimator with robust variance estimation. We meta-analyzed ERP-STB combinations that had at least three effect sizes across two or more studies. ResultsA qualitative review found that for each ERP and STB combination, the literature is highly mixed. Our meta-analyses largely did not find significant relationships between STBs and ERPs. We also found that the literature is likely severely underpowered, with most studies only being sufficiently powered to detect unrealistically large effect sizes. ConclusionsOur results provided little-to-no support for a reliable relationship between the ERPs assessed and STBs. However, the current literature is severely underpowered, and there are many methodological weaknesses that must be resolved before making this determination. We recommend large-scale collaboration and improvements in measurement practices to combat the issues in this literature.

neuroscience↗

bioRxiv2020

Acute Stress Reduces Reward-Related Neural Activity: Evidence from the Reward Positivity

Stress and blunted reward processing are risk factors for mood disorders, including Major Depressive Disorder (MDD). The experience of acute stress reduces fMRI correlates of reward-related neural activity; however, few studies have examined how acute stress impacts measures of reward derived from event-related potentials (ERPs). The current study examined the impact of an acute stressor on the Reward Positivity (RewP), an ERP that indexes reward sensitivity, in twenty-seven college students. Participants completed a monetary reward task while they placed their left hand in cold water set at 13 degrees Celsius (i.e., acute stress condition) and again while their hand was placed in room temperature water (i.e., control condition). These conditions were separated by one week and performed in a counter-balanced order across participants. The results revealed that the RewP amplitude was blunted in the acute stress condition compared to the control condition. Moreover, there was a trend toward this effect interacting with self-reported depressive symptoms: the RewP was only reduced among individuals who reported low depressive symptoms. The current study suggests that an acute stressor reduces the RewP, and that this effect might be moderated by current depressive symptoms. Future studies might examine the temporal association between reward processing and stress --and how they interact to predict depressive symptoms.

neuroscience↗