Neural Patterns of the Implicit Association Test

Explicit and implicit cognitive processes of the public towards people who stutter

PURPOSE

The Public Opinion Survey of Human Attributes - Stuttering (POSHA-S, St. Louis, 2013) was developed as a standard measure of public attitudes about people who stutter. As with any survey-based methods, threats to validity may occur because of social desirability bias. Using computer mouse-tracking, we were interested in observing changes in cognition that are manifested in intentionality through action by evaluating underlying cognitive processes that drive social judgments of people who stutter.

METHODS

Twenty-two women, 1 non-binary person, and 47 men reported using a computer mouse to complete an online, remote, and modified version of the POSHA-S. Responses were categorized as correct/helpful or incorrect/unhelpful relative to each component of the POSHA-S and were used as measures of explicit cognitive processes. Computer-mouse trajectory metrics, including area under the curve (AUC) and reaction time (RT), were used to measure implicit cognitive processes.

RESULTS

Although participants' explicit responses were significantly more likely to be correct/helpful than incorrect/unhelpful, with endorsement of correct/helpful prompts 77 % of the time, participants also endorsed incorrect/unhelpful prompts more than half (i.e., 52 %) of the time. Familiarity with people who stutter was associated with disagreeing with incorrect/unhelpful prompts. As indicated by greater AUC, participants exhibited significantly more implicit cognitive processes indicating competition when responding "disagree" compared to "agree", regardless of whether the prompts were correct/helpful or incorrect/unhelpful. Similarly, participants took significantly longer to respond to prompts with "disagree" rather than "agree".

CONCLUSION

The findings of this study offer evidence of participants reporting cognitive processes that are overall more correct/helpful than incorrect/unhelpful, in their explicit responses to the dichotomous response tasks of the POSHA-S. However, these findings are tempered by evidence of a tendency to agree with statements in the measure and suggest the need for further research to increase understanding of how to measure and improve explicit and implicit cognitive processes related to people who stutter.

Expectancy Violation: Climate Change Associations May Reveal Underlying Brain-Evoked Responses of Implicit Attitudes

The development of programs and campaigns to promote climate change awareness and actions should account for implicit attitudes to make them effective. Alongside behavioural measures, it is important to investigate and understand the neural mechanisms underlying unconscious beliefs, and opinions and how external factors can influence them. Therefore, this study administered a Single-Category Implicit Association Test to 22 healthy volunteers while acquiring EEG signals. After an automatic preprocessing pipeline was applied, 1000ms-long epochs were extracted from cleaned EEG data for target words only. Latencies and amplitudes were computed in specific brain regions and time intervals for the P1, N1, P2 (both occipital and frontal), P3, and N4 (both frontal and frontocentral) event-related potentials (ERPs). Statistical analysis has highlighted that incongruent associations elicited significantly shorter N1 latencies, which may be due to stimuli familiarisation, longer P3 latencies, which can be related to the allocation of more attentional resources, and larger N4 amplitudes, which suggest greater cognitive efforts. Correlation analysis has also found a significant relationship between the amplitude of the N4 and explicit behaviour. These results suggest that ERPs can highlight different mental processes involved in violating social expectations towards climate change and that their features may be used to support behavioural measures in assessing implicit attitudes more reliably.

Functional Connectivity Analysis of Prej udice Among Colombian Armed Conflict Former Actors

Despite institutional efforts, reconciliation among former actors of the Colombian armed conflict has yet to be achieved, with prejudice being one direct driver of this drawback. We present an EEG-based functional connectivity study applied to four groups of former actors who completed an Implicit Association Test designed to measure prejudice toward victims or combatants. We analyzed seven measures of functional connectivity calculated in six different frequency bands and two experimental conditions. In the behavioral task, we found more prejudice toward victims from the same victims and more prejudice of civilians toward combatants. For the connectivity measures, we found differences in theta band among the victims' and ex-paramilitaries' groups concerning the civilians' and ex-guerrillas' groups, and differences in the beta2 band among the victims' and ex-guerrillas' groups concerning the ex-paramilitaries' group. The results help us design more effective socio-cognitive interventions to reduce prejudice.

Mothers' and fathers' neural responses toward gender-stereotype violations by their own children

Gender stereotypes facilitate people's processing of social information by providing assumptions about expected behaviors and preferences. When gendered expectations are violated, people often respond negatively, both on a behavioral and neural level. Little is known about the impact of family kinship on the behavioral and neural reactions to gender-stereotype violations. Therefore, we examined whether parents show different responses when gender stereotypes are violated by their own children vs unknown children. The sample comprised 74 Dutch families with a father (Mage = 37.54), mother (Mage = 35.83), son, and daughter aged 3-6 years. Electroencephalography measurements were obtained while parents viewed pictures of their own and unknown children paired with toy or problem behavior words that violated or confirmed gender stereotypes. In half of the trials, parents evaluated the appropriateness of toy-gender and behavior-gender combinations. Parents showed stronger late positive potential amplitudes toward gender stereotype-violating behaviors by own children compared to unknown children. Moreover, parents' P1 responses toward gender stereotype-violating child behaviors were stronger for boys than for girls and for parents who evaluated gender-stereotype violations as less appropriate than gender-stereotype confirmations. These findings indicated that gender-stereotype violations by parents' own children are particularly salient and viewed as less appropriate than gender-stereotype confirmations.

Women are expected to smile: Preliminary evidence for the role of gender in the neurophysiological processing of adult emotional faces in 3-year-old children

Children form stereotyped expectations about the appropriateness of certain emotions for men versus women during the preschool years, based on cues from their social environments. Although ample research has examined the development of gender stereotypes in children, little is known about the neural responses that underlie the processing of gender-stereotyped emotions in children. Therefore, the current study examined whether 3-year-olds differ in the neural processing of emotional stimuli that violate gender stereotypes (i.e., male faces with fearful or happy expressions) or confirm gender stereotypes (i.e., female faces with fearful or happy expressions), and whether boys and girls differ in their neural processing of the violation and confirmation of gender stereotypes. Data from 72 3-year-olds (±6 months, 43% boy) were obtained from the YOUth Cohort Study. Electroencephalography data were obtained when children passively viewed male and female faces displaying neutral, happy, or fearful facial expressions. This study provided first indications that happy male faces elicited larger P1 amplitudes than happy female faces in preschool children, which might reflect increased attentional processing of stimuli that violate gender stereotypes. Moreover, there was preliminary evidence that girls had larger negative central (Nc) responses, associated with salience processing, toward female happy faces than male happy faces, whereas boys had larger Nc responses toward male happy faces than female happy faces. No gender differences were found in the processing of neutral and fearful facial expressions. Our results indicate that electroencephalography measurements can provide insights into preschoolers' gender-stereotype knowledge about emotions, potentially by looking at the early occipital and late fronto-central responses.

To run or not to run? Differences in implicit attitudes towards running: An EEG study

OBJECTIVE

To understand the reasons for individuals do or do not exercise, we examined differences in implicit (affective and instrumental) attitudes between runners and non-runners.

METHODS

In conjunction with electroencephalography (EEG) technology, 31 participants completed the affective and instrumental implicit associations test (IAT).

RESULTS

Behavioural results showed that runners had more positive implicit (affective and instrumental) attitudes than non-runners. EEG results further explained the underlying mechanisms for the differences, namely that runners had higher cortical functional connectivity in the compatible condition than in the incompatible condition, while non-runners had the opposite results.

CONCLUSIONS

Higher levels of neural processing efficiency were required for runners to perceive affective expectations towards running. Furthermore, ERP indicators (N1 amplitudes of incompatible tasks) can be used as valid criteria for potentially predicting exercise. This contributed to understanding why individuals do or do not exercise. Further research should focus on the effects of implicit attitudes towards exercise.

Electroencephalographic oscillations of alpha and beta rhythms during phrase-guessing procedure

Phrases-guessing is one of the essential reasoning abilities in problem solving for human beings. However, it is still an open question about why individuals perform differently during the same reasoning task. In this study, we utilized a bilingual phrase-guessing task to explore the neural activities under the individually different performances with electroencephalography. Participants who had no knowledge of Greek were required to guess the meaning of a Greek phrase (long or short in length) by making an either-or selection as to which translation-equivalent Chinese word corresponds to Greek word. Names of color were used as experimental stimuli for which two Chinese words denoted the same color with one as a conventional color name and the other as a novel color name. The experiment yielded length of phrases (long vs. short) and novelty of phrases (novel vs. conventional) as variables. The behavioral results revealed significant length-by-novelty interaction on the number of selections. However, neither main effects nor interactive effects were found on response time. Further, the amplitude spectrums of high alpha rhythm, low alpha rhythm, and low beta rhythm during the task were positively associated with the participants' number of selections for a long Greek phrase with a novel and complex Chinese phrase (LNc) and a short Greek phrase with a conventional Chinese phrase (SCo), while negatively correlated with the response time of selections for LNc and SCo. Our findings suggested that the consistency between participants' behavior and electrophysiological oscillations (alpha and beta bands) could be employed as biomarkers for decoding the phrase-guessing procedure.

Event-Related Potential Markers of Suicidality in Adolescents

BACKGROUND

Implicit cognitive markers may assist with the prediction of suicidality beyond clinical risk factors. The aim of this study was to investigate neural correlates associated with the Death/Suicide Implicit Association Test (DS-IAT) via event-related potentials (ERP) in suicidal adolescents.

METHODS

Thirty inpatient adolescents with suicidal ideations and behaviors (SIBS) and 30 healthy controls from the community were recruited. All participants underwent 64-channel electroencephalography, DS-IAT, and clinical assessments. Hierarchical generalized linear models with spatiotemporal clustering were used to identify significant ERPs associated with the behavioral outcome of DS-IAT (D scores) and group differences.

RESULTS

Behavioral results (D scores) showed that the adolescents with SIBS had stronger implicit associations between "death" and "self" than the healthy group (P = .02). Within adolescents with SIBS, participants with stronger implicit associations between "death" and "self" reported more difficulty in controllability of suicidal ideation in the past 2 weeks based on the Columbia-Suicide Severity Rating Scale (P = .03). For the ERP data, the D scores and N100 component over the left parieto-occipital cortex had significant correlations. Significant group differences without behavioral correlation were observed for a second N100 cluster (P = .01), P200 (P = .02), and late positive potential (5 clusters, all P ≤ .02). Exploratory predictive models combining both neurophysiological and clinical measures distinguished adolescents with SIBS from healthy adolescents.

CONCLUSIONS

Our results suggest that N100 may be a marker of attentional resources involved in the distinction of stimuli that are congruent or incongruent to associations between death and self. Combined clinical and ERP measures may have utility in future refinements of assessment and treatment approaches for adolescents with suicidality.

Eye-tracking correlates of the Implicit Association Test

Raising awareness of environmental challenges represents an important issue for researchers and scientists. As public opinion remains ambiguous, implicit attitudes toward climate change must be investigated. A custom Single-Category Implicit Association Test, a version of the Implicit Association Test, was developed to assess climate change beliefs. It was administered to 20 subjects while eye movements were tracked using a smart glasses system. Eye gaze patterns were analysed to understand whether they could reflect implicit attitudes toward nature. Recurrence Quantification Analysis was performed to extract 13 features from the eye-tracking data, which were used to perform statistical analyses. Significant differences were found between target stimuli (words related to climate change) and bad attributes in reaction time, and between target stimuli and good attributes in diagonal length entropy, suggesting that eye-tracking may provide an alternative source of information to electroencephalography in modeling and predicting implicit attitudes.

Influence of bodily states on cognition: A web-based study in individuals with body integrity dysphoria

There is a constant reciprocal flow of information between the malleable sensorimotor states of the body and cognitive functions, and some embodied cognition approaches argue that many cognitive-affective mechanisms depend on the physical characteristics of the body. To examine such influences of bodily state, the current study compared patients with body integrity dysphoria (BID) with an amputation desire of the lower limb to a healthy control group on an Implicit Association Test for self-identity and self-esteem, and a pain evaluation task. Patients with BID completed the tasks once while emulating their desired bodily state and once while simulating their undesired bodily state, while healthy controls were split into two groups: one control group completed the experiment once while either sitting on one leg and once while sitting in a normal position, whereas the other control group completed both experiments while sitting in a normal position. Results demonstrate that patients with BID implicitly identify more strongly with an amputated body, whereas healthy controls demonstrate stronger identification with a complete body, independent of bodily state. Furthermore, implicit self-esteem did not differ between the groups and was also not modulated by bodily state manipulation in any of the groups. Pain evaluation ratings were not influenced by bodily state manipulation, perspective, or consistency. Pain forced choice response times, however, revealed that individuals with BID were faster to judge whether the stimulus depicted was painful when simulating their desired bodily state. These results provide insightful information to how both the subjective sense of body, as well as more transient alterations of objective sensorimotor states of the physical body may exert selective pressure on certain cognitive tasks.

A neurocognitive approach to studying processes underlying parents' gender socialization

Parental gender socialization refers to ways in which parents teach their children social expectations associated with gender. Relatively little is known about the mechanisms underlying gender socialization. An overview of cognitive and neural processes underlying parental gender socialization is provided. Regarding cognitive processes, evidence exists that parents' implicit and explicit gender stereotypes, attitudes, and gendered attributions are implicated in gender socialization. Other cognitive factors, such as intergroup attitudes, gender essentialism, internal motivation for parenting without gender stereotypes, gender identity, and conflict resolution are theoretically relevant mechanisms underlying gender socialization, but need further investigation. Regarding neural processes, studies demonstrated that attentional processing, conflict monitoring, behavior regulation, and reward processing might underlie stereotypes and biased behavior. However, more research is necessary to test whether these neural processes are also related to parental gender socialization. Based on this overview, a framework is presented of neural and cognitive factors that were theoretically or empirically related to gender socialization.

The encoding of race during face processing, an event-related potential study

It is well known that adults spontaneously classify people into social categories and this categorization in turn guides their cognition and behavior. A wealth of research has examined how people perceive race and investigated the effect of race on social behavior. But what about race encoding? Although considerable behavioral research has investigated the encoding of race, that is, the social categorization by race, the neural underpinning of it is largely underexplored. To investigate the time course of race encoding, the current study employed a modified category verification task and a multivariate analyzing approach. We found that racial information became decodable from event-related potential topographies as early as about 200 ms after stimulus onset. At this stage, the brain can differentiate different races in a task-relevant manner. Nonetheless, it is not until 100 ms later that racial information is encoded in a socially relevant manner (own- versus other-race). Importantly, perceptual differentiation not only occurs before the encoding of the race but actually influences it: the faces that are more easily perceptually categorized are actually encoded more readily. Together, we posit that the detection and the encoding of race are decoupled although they are not completely independent. Our results provide powerful constraints toward the theory-building of race.

Neural Rhythmic Underpinnings of Intergroup Bias: Implications for Peace-Building Attitudes and Dialogue

Intergroup bias is a ubiquitous socio-cognitive phenomenon that, while sustaining human dependence on group living, often leads to prejudice, inequity, and violence; yet, its neural underpinnings remain unclear. Framed within the Israeli-Palestinian conflict and targeting youth, this study utilized magnetoencephalography to describe intrinsic neural oscillatory processes that represent the intergroup bias and may link with engagement in peacemaking in order to shed further light on the neural mechanisms underpinning intergroup conflict. Across the oscillatory spectrum, from very low to very high frequency bands, the only rhythm found to underlie the intergroup bias was the alpha rhythm. Alpha was continuously activated across the task and integrated a rapid perceptual component in occipital cortex with a top-down cognitive-control component in medial cingulate cortex. These components were distinctly associated with real-life intergroup dialog style and expressed attitudes that promote active engagement in peacemaking. Our findings suggest that the cortical alpha rhythm plays a crucial role in sustaining intergroup bias and address its impact on concrete intergroup experiences. Results highlight the need to provide opportunities for active peace-building dialog to youth reared amidst intractable conflicts.

Brain responses of dysphoric and control participants during a self-esteem implicit association test

Previous studies have reported lowered implicit self-esteem at the behavioral level among depressed individuals. However, brain responses related to the lowered implicit self-esteem have not been investigated in people with depression. Here, event-related potentials were measured in 28 dysphoric participants (individuals with elevated amounts of depressive symptoms) and 30 control participants during performance of an implicit association task (IAT) suggested to reflect implicit self-esteem. Despite equivalent behavioral performance, differences in brain responses were observed between the dysphoric and the control groups in late positive component (LPC) within 400-1,000 ms poststimulus latency. For the dysphoric group, self-negativity mapping stimuli (me with negative word pairing and not-me with positive word pairing) induced significantly larger LPC amplitude as compared to self-positivity mapping stimuli (me with positive pairing and not-me with negative pairing), whereas the control group showed the opposite pattern. These results suggest a more efficient categorization toward implicit self-is-negative association, possibly reflecting lower implicit self-esteem among the dysphoric participants, in comparison to the controls. These results demonstrate the need for further investigation into the functional significance of LPC modulation during IAT and determination of whether LPC can be used as a neural marker of depressive-related implicit self-esteem.

Anxiety Sensitivity and Arousal Symptom Implicit Association Task Performance: An Event-Related Potential Study of Cognitive Processing of Anxiety-Relevant Stimuli

BACKGROUND

Anxiety sensitivity (AS), or the fear of anxious arousal, is a transdiagnostic risk factor. Despite the proliferation of self-report research showing AS is related to anxiety, cognitive processes underlying AS are poorly understood. Specifically, AS may reflect processes related to early attentional orientation and response monitoring (reflecting automatic processes), or later engagement and assigning emotional salience towards stimuli (reflecting conscious processes).

METHODS

To elucidate cognitive processes underlying AS, event-related potential (ERP) components were elicited in the current study during a novel implicit association task (IAT) in which participants paired self (versus other) words with anxious arousal (versus calm) words. Analyses were then conducted in a sample of community adults (N = 67; M age 39.43, SD = 15.33, 61.2% female) to investigate the association between AS and ERP markers indicative of cognitive processing derived during the IAT.

RESULTS

AS was not related to performance on the arousal-IAT and that ERP components did not differ by IAT condition. AS predicted overall late positive potential (LPP) amplitude, particularly in the me/anxiety condition. Elevated IAT scores (reflecting greater ease pairing self-words with anxiety-words) predicted greater P300 amplitude in the me/anxiety condition.

LIMITATIONS

The sample was relatively small, and bottom-up processes were not assessed.

CONCLUSIONS

These findings are inconsistent with the claim that AS is related to top-down cognitive processes driving self-arousal automatic associations. Instead, AS may relate to cognitive processes regulating emotional engagement with stimuli. Further investigations of cognitive processes underlying AS are needed to inform novel interventions targeting AS.

Altered anterior cingulate glutamatergic metabolism in depressed adolescents with current suicidal ideation

The anterior cingulate cortex (ACC) is involved in emotion regulation and salience processing. Prior research has implicated ACC dysfunction in suicidal ideation (SI) and suicidal behavior. This study aimed to quantify ACC glutamatergic concentrations and to examine relationships with SI in a sample of healthy and depressed adolescents. Forty adolescents underwent clinical evaluation and proton magnetic resonance spectroscopy (1H-MRS) at 3 T, utilizing a 2-dimensional J-averaged PRESS sequence sampling a medial pregenual ACC voxel. Cerebrospinal fluid-corrected ACC metabolite concentrations were compared between healthy control (HC, n = 16), depressed without SI (Dep/SI-, n = 13), and depressed with SI (Dep/SI+, n = 11) youth using general linear models covarying for age, sex, and psychotropic medication use. Relationships between ACC metabolites and continuous measures of SI were examined using multiple linear regressions. ROC analysis was used to determine the ability of glutamate+glutamine (Glx) and the N-acetylaspartate (NAA)/Glx ratio to discriminate Dep/SI- and Dep/SI+ adolescents. Dep/SI+ adolescents had higher Glx than Dep/SI- participants (padj = 0.012) and had lower NAA/Glx than both Dep/SI- (padj = 0.002) and HC adolescents (padj = 0.039). There were significant relationships between SI intensity and Glx (pFDR = 0.026), SI severity and NAA/Glx (pFDR = 0.012), and SI intensity and NAA/Glx (pFDR = 0.004). ACC Glx and NAA/Glx discriminated Dep/SI- from Dep/SI+ participants. Uncoupled NAA-glutamatergic metabolism in the ACC may play a role in suicidal ideation and behavior. Longitudinal studies are needed to establish whether aberrant glutamatergic metabolism corresponds to acute or chronic suicide risk. Glutamatergic biomarkers may be promising targets for novel risk assessment and interventional strategies for suicidal ideation and behavior.

Teachers' Implicit Attitudes Toward Students From Different Social Groups: A Meta-Analysis

Teachers' attitudes toward their students have been associated with differential teachers' expectations and, in turn, with students' educational pathways. Theories of social cognition can explain the link between attitudes and behavior. In this regard, the distinction between implicit and explicit attitudes is worth to be considered, whereby implicit attitudes are automatically activated when the attitude object is present and guide automatic behavior. In contrast, explicit attitudes infer deliberation and reflection, hence affecting controlled behavior. As teachers often are required to act immediately in situations that do not allow for thoughtful reflection due to time restraints, teachers' implicit attitudes concerning different student groups with shared characteristics, such as gender or ethnicity, may be especially important when considering teachers' behavior in relation to students' educational pathways. This notion is reflected by an increased interest in adopting implicit methodology in the educational domain. Over the last 10 years, several studies have been conducted in different countries, involving in- and pre-service teachers and investigating their attitudes toward different student groups. Estimates of effects have varied and may be affected by sampling bias. To systematically review and integrate data from different studies, this meta-analysis focuses on teachers' implicit attitudes. Following the systematic search of the database and initial screening, 43 articles were identified from which 22, describing 34 studies, were retained for the meta-analysis after further inspection. First analyses revealed an estimated average effect size of 0.56 for implicit attitudes in favor of non-marginalized groups. As there was a large extent of heterogeneity between studies, several moderator variables were investigated. Results showed that the employed implicit measure and stimulus materials as well as the student target group affected the effect sizes. Low or non-significant relationships were reported between implicit and explicit attitudes. Findings are discussed in terms of theory and future research.

The impact of nicotine dose and instructed dose on smokers' implicit attitudes to smoking cues: An ERP study

It is unclear whether nicotine and perceived nicotine exposure can influence automatic evaluations of cigarette stimuli. In the present study, we investigated the effects of nicotine dose and instructed dose on motivational responses to smoking cues. Forty overnight nicotine-deprived smokers completed an Implicit Association Test (IAT) at each of the four laboratory sessions in a balanced-placebo design that crossed nicotine dose (Given-NIC [given nicotine] vs. Given-DENIC [given denicotinized]) with instructed dose expectancy (Told-NIC [told-nicotine] vs. Told-DENIC. [told-denicotinized]). We measured participants' behavioral performance, including reaction time (RT) and accuracy rate, and the early posterior negativity (EPN) component using the event-related potential (ERP) technique to the target pictures. During congruent trials when the categorization condition was smoking or unpleasant, smokers had greater classification accuracy, shorter RT latency, and greater EPN amplitudes compared to the incongruent trials when the categorization condition was smoking or pleasant. The Given-NIC condition was associated with increased classification accuracy, longer RT latency, and decreased EPN amplitudes compared to the Given-DENIC condition. Similarly, the Told-NIC condition was associated with increased accuracy and decreased EPN amplitudes compared to the Told-DENIC condition, but with shorter RT latency. Cigarette-related pictures produced greater EPN amplitudes than neutral pictures. Both behavioral and ERP results suggest that smokers have negative implicit attitudes toward smoking. While both nicotine dose and expected dose facilitated stimulus categorization, there was no evidence that either factor altered smokers' negative attitudes toward smoking cues. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Neural processing of gendered information is more robustly associated with mothers' gendered communication with children than mothers' implicit and explicit gender stereotypes

Processes like gender socialization (the ways in which parents convey information to their children about how girls and boys should behave) often happen unconsciously and might therefore be studied best with neuroscientific measures. We examined whether neural processing of gender-stereotype-congruent and incongruent information is more robustly related to mothers' gendered socialization of their child than mothers' implicit and explicit gender stereotypes. To this end, we examined event-related potentials (ERPs) of mothers (N = 35) completing an implicit gender-stereotype task and mothers' gender stereotypes in relation to observed gendered communication with their child (2-6 years old) in a naturalistic picture-book-reading setting. Increased N2 activity (previously related to attentional processes) to gender stimuli in the implicit gender-stereotype task was associated with mothers' positive evaluation of similar gendered behaviors and activities in the picture book they read with their child. Increased P300 activity (previously related to attention to unexpected events) to incongruent trials in the gender-stereotype task was associated with a more positive evaluation of congruent versus incongruent pictures. Compared to mothers' gender stereotypes, neural processing of gendered information was more robustly related to how mothers talk to their children about boys' and girls' stereotype-congruent and incongruent behavior, and masculine and feminine activities.

Anti-TNFα therapy in IBD alters brain activity reflecting visceral sensory function and cognitive-affective biases

Background

In inflammatory bowel disease (IBD), immune activation with increased circulating TNF-α is linked to the intensity of gastrointestinal symptoms and depression or anxiety. A central feature of depression is cognitive biases linked to negative attributions about self, the world and the future. We aimed to assess the effects of anti-TNFα therapy on the central processing of self-attribution biases and visceral afferent information in patients with Crohn’s disease.

Methods

We examined 9 patients with Crohn’s disease (age 26.1±10.6. yrs, 5 female, 5 ileocolonic, 2 colonic and 2 ileal disease) during chronic anti-TNFα therapy (5 adalimumab, 4 infliximab). Patients were studied twice in randomized order before and after anti-TNFα administration. On each occasion patients underwent functional magnetic resonance imaging (fMRI) of the brain during a test of implicit attribution biases regarding sickness/health and undertook a standardized nutrient challenge.

Results

Following anti-TNFα treatment, ratings of ‘fullness’ following nutrient challenge reduced compared to pre-treatment ratings (p<0.05). Reaction times revealed improved processing of self-related and positive health words, consistent with improved implicit sense of wellbeing that correlated with improvements in sensory function after treatment (r = 0.67, p<0.05). Treatment-associated improvements in implicit processing were mirrored by alterations of prefrontal, amygdala, posterior cingulate and visual regions. Between patients, the degree of functional amygdala change was additionally explained by individual differences in attention regulation and body awareness rankings.

Conclusion

In patients with Crohn’s disease, anti-TNFα administration reduces visceral sensitivity and improves implicit cognitive-affective biases linked to alterations in limbic (amygdala) function.

The Neural Correlates of Implicit Cognitive Bias Toward Internet-Related Cues in Internet Addiction: An ERP Study

Internet addiction is a sort of non-psychoactive substance dependence. The Implicit Association Test (IAT) is used to measure implicit cognition. Event-related potential (ERP) is one of the most widely used methods in cognitive neuroscience research to investigate the physiological correlates of cognitive activity associated with processing information. Further investigating the ERP characteristics of implicit cognitive bias in Internet addiction would be helpful in understanding the nature of Internet addiction. This study investigated the ERP characteristics of implicit cognitive bias in Internet addiction. The participants included 60 Internet-addicted individuals (IAG) and 60 normal controls (NCG). All participants were measured with ERPs using the IAT. The results showed that there was a significant difference in the Internet-related IAT effect for reaction times between IAG and NCG, and there were stronger positive implicit associations toward Internet related cues in IAG than NCG. Using P1, N2, P3, and N4 as dependent variables, a mixed repeated-measures analysis of variance (ANOVA) on the mean latencies and mean amplitudes revealed a significant interaction between the groups (IAG vs. NCG) and stimulus condition (compatible trials vs. incompatible trials) for the N2 and P3 amplitudes; the simple effects analysis showed that the N2 and P3 amplitudes were larger under the IAG-compatible trial conditions than under the IAG-incompatible trial conditions. In the IAG group, the positive implicit associations with Internet-related cues elicited larger N2 and P3 amplitudes at the occipital lobe sites. These results indicated that Internet addictive individuals show stronger positive implicit associations toward Internet-related cues, and the positive implicit associations toward Internet-related cues elicited ERP changes at occipital lobe sites.

The temporal dynamics of reversal learning: P3 amplitude predicts valence-specific behavioral adjustment

Adapting behavior to dynamic stimulus-reward contingences is a core feature of reversal learning and a capacity thought to be critical to socio-emotional behavior. Impairment in reversal learning has been linked to multiple psychiatric outcomes, including depression, Parkinson's disorder, and substance abuse. A recent influential study introduced an innovative laboratory reversal-learning paradigm capable of disentangling the roles of feedback valence and expectancy. Here, we sought to use this paradigm in order to examine the time-course of reward and punishment learning using event-related potentials among a large, representative sample (N=101). Three distinct phases of processing were examined: initial feedback evaluation (reward positivity, or RewP), allocation of attention (P3), and sustained processing (late positive potential, or LPP). Results indicate a differential pattern of valence and expectancy across these processing stages: the RewP was uniquely related to valence (i.e., positive vs. negative feedback), the P3 was uniquely associated with expectancy (i.e., unexpected vs. expected feedback), and the LPP was sensitive to both valence and expectancy (i.e., main effects of each, but no interaction). The link between ERP amplitudes and behavioral performance was strongest for the P3, and this association was valence-specific. Overall, these findings highlight the potential utility of the P3 as a neural marker for feedback processing in reversal-based learning and establish a foundation for future research in clinical populations.