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Cortical deficits of emotional face processing in adults with ADHD: Its relation to social cognition and executive function

Although it has been shown that adults with attention-deficit hyperactivity disorder (ADHD) have impaired social cognition, no previous study has reported the brain correlates of face valence processing. This study looked for behavioral, neuropsychological, and electrophysiological markers of emotion processing for faces (N170) in adult ADHD compared to controls matched by age, gender, educational level, and handedness. We designed an event-related potential (ERP) study based on a dual valence task (DVT), in which faces and words were presented to test the effects of stimulus type (faces, words, or face-word stimuli) and valence (positive versus negative). Individual signatures of cognitive functioning in participants with ADHD and controls were assessed with a comprehensive neuropsychological evaluation, including executive functioning (EF) and theory of mind (ToM). Compared to controls, the adult ADHD group showed deficits in N170 emotion modulation for facial stimuli. These N170 impairments were observed in the absence of any deficit in facial structural processing, suggesting a specific ADHD impairment in early facial emotion modulation. The cortical current density mapping of N170 yielded a main neural source of N170 at posterior section of fusiform gyrus (maximum at left hemisphere for words and right hemisphere for faces and simultaneous stimuli). Neural generators of N170 (fusiform gyrus) were reduced in ADHD. In those patients, N170 emotion processing was associated with performance on an emotional inference ToM task, and N170 from simultaneous stimuli was associated with EF, especially working memory. This is the first report to reveal an adult ADHD-specific impairment in the cortical modulation of emotion for faces and an association between N170 cortical measures and ToM and EF.

The Neural Basis of Decision-Making and Reward Processing in Adults with Euthymic Bipolar Disorder or Attention-Deficit/Hyperactivity Disorder (ADHD)

Background Attention-deficit/hyperactivity disorder (ADHD) and bipolar disorder (BD) share DSM-IV criteria in adults and cause problems in decision-making. Nevertheless, no previous report has assessed a decision-making task that includes the examination of the neural correlates of reward and gambling in adults with ADHD and those with BD. Methodology/Principal Findings We used the Iowa gambling task (IGT), a task of rational decision-making under risk (RDMUR) and a rapid-decision gambling task (RDGT) which elicits behavioral measures as well as event-related potentials (ERPs: fERN and P3) in connection to the motivational impact of events. We did not observe between-group differences for decision-making under risk or ambiguity (RDMUR and IGT); however, there were significant differences for the ERP-assessed RDGT. Compared to controls, the ADHD group showed a pattern of impaired learning by feedback (fERN) and insensitivity to reward magnitude (P3). This ERP pattern (fERN and P3) was associated with impulsivity, hyperactivity, executive function and working memory. Compared to controls, the BD group showed fERN- and P3-enhanced responses to reward magnitude regardless of valence. This ERP pattern (fERN and P3) was associated with mood and inhibitory control. Consistent with the ERP findings, an analysis of source location revealed reduced responses of the cingulate cortex to the valence and magnitude of rewards in patients with ADHD and BD. Conclusions/Significance Our data suggest that neurophysiological (ERPs) paradigms such as the RDGT are well suited to assess subclinical decision-making processes in patients with ADHD and BD as well as for linking the cingulate cortex with action monitoring systems.

Neuropsychological functioning in adult bipolar disorder and ADHD patients: A comparative study

Bipolar disorder (BD) and adult attention deficit hyperactivity disorder (ADHD) usually manifest with shared clinical symptoms, proving quite challenging to thoroughly differentiate one from another. Previous research has characterized these two disorders independently, but no study compared both pathologies from a neuropsychological perspective. The aim of this study was to compare the neuropsychological profile of adult ADHD and BD with each other and against a control group, in order to understand the way in which comprehensive cognitive assessment can contribute to their discrimination as distinct clinical entities as well as their differential diagnosis. All groups were successfully matched for age, sex, years of education, and premorbid IQ. Participants were assessed with an extensive neuropsychological battery evaluating multiple domains. Compared to controls, BD patients had a poorer performance on immediate verbal memory tasks. Both clinical groups exhibited significantly lower scores than controls on the recognition phase of verbal and non-verbal memory tasks, as well as on a task of executive functioning with high working memory demand. Noticeably, however, ADHD had significantly better performance than BD on the recognition phase of both the Rey list memory task and the Rey Figure. The better performance of ADHD patients over BD may reflect the crucial role of the executive component on their memory deficits and gives empirical support to further differentiate the neuropsychological profile of BD and adult ADHD patients in clinical practice.

From neural signatures of emotional modulation to social cognition: individual differences in healthy volunteers and psychiatric participants

It is commonly assumed that early emotional signals provide relevant information for social cognition tasks. The goal of this study was to test the association between (a) cortical markers of face emotional processing and (b) social-cognitive measures, and also to build a model which can predict this association (a and b) in healthy volunteers as well as in different groups of psychiatric patients. Thus, we investigated the early cortical processing of emotional stimuli (N170, using a face and word valence task) and their relationship with the social-cognitive profiles (SCPs, indexed by measures of theory of mind, fluid intelligence, speed processing and executive functions). Group comparisons and individual differences were assessed among schizophrenia (SCZ) patients and their relatives, individuals with attention deficit hyperactivity disorder (ADHD), individuals with euthymic bipolar disorder (BD) and healthy participants (educational level, handedness, age and gender matched). Our results provide evidence of emotional N170 impairments in the affected groups (SCZ and relatives, ADHD and BD) as well as subtle group differences. Importantly, cortical processing of emotional stimuli predicted the SCP, as evidenced by a structural equation model analysis. This is the first study to report an association model of brain markers of emotional processing and SCP.

Neural Processing of Emotional Facial and Semantic Expressions in Euthymic Bipolar Disorder (BD) and Its Association with Theory of Mind (ToM)

Background Adults with bipolar disorder (BD) have cognitive impairments that affect face processing and social cognition. However, it remains unknown whether these deficits in euthymic BD have impaired brain markers of emotional processing. Methodology/Principal Findings We recruited twenty six participants, 13 controls subjects with an equal number of euthymic BD participants. We used an event-related potential (ERP) assessment of a dual valence task (DVT), in which faces (angry and happy), words (pleasant and unpleasant), and face-word simultaneous combinations are presented to test the effects of the stimulus type (face vs word) and valence (positive vs. negative). All participants received clinical, neuropsychological and social cognition evaluations. ERP analysis revealed that both groups showed N170 modulation of stimulus type effects (face > word). BD patients exhibited reduced and enhanced N170 to facial and semantic valence, respectively. The neural source estimation of N170 was a posterior section of the fusiform gyrus (FG), including the face fusiform area (FFA). Neural generators of N170 for faces (FG and FFA) were reduced in BD. In these patients, N170 modulation was associated with social cognition (theory of mind). Conclusions/Significance This is the first report of euthymic BD exhibiting abnormal N170 emotional discrimination associated with theory of mind impairments.

Functional Connectivity and Temporal Variability of Brain Connections in Adults with Attention Deficit/Hyperactivity Disorder and Bipolar Disorder

Objectives: To assess brain functional connectivity and variability in adults with attention deficit/hyperactivity disorder (ADHD) or euthymic bipolar disorder (BD) relative to a control (CT) group. Methods: Electroencephalography (EEG) was measured in 35 participants (BD = 11; ADHD = 9; CT = 15) during an eyes-closed 10-min rest period, and connectivity and graph theory metrics were computed. A coefficient of variation (CV) computed also the connectivitys temporal variability of EEG. Multivariate associations between functional connectivity and clinical and neuropsychological profiles were evaluated. Results: An enhancement of functional connectivity was observed in the ADHD (fronto-occipital connections) and BD (diffuse connections) groups. However, compared with CTs, intrinsic variability (CV) was enhanced in the ADHD group and reduced in the BD group. Graph theory metrics confirmed the existence of several abnormal network features in both affected groups. Significant associations of connectivity with symptoms were also observed. In the ADHD group, temporal variability of functional connections was associated with executive function and memory deficits. Depression, hyperactivity and impulsivity levels in the ADHD group were associated with abnormal intrinsic connectivity. In the BD group, levels of anxiety and depression were related to abnormal frontotemporal connectivity. Conclusions: In the ADHD group, we found that intrinsic variability was associated with deficits in cognitive performance and that connectivity abnormalities were related to ADHD symptomatology. The BD group exhibited less intrinsic variability and more diffuse long-range brain connections, and those abnormalities were related to interindividual differences in depression and anxiety. These preliminary results are relevant for neurocognitive models of abnormal brain connectivity in both disorders.

Dysfunctional cognitions and their emotional, behavioral, and functional correlates in adults with attention deficit hyperactivity disorder (ADHD): is the cognitive-behavioral model valid?

Objective: To investigate the presence of dysfunctional cognitions in adults with ADHD and to determine whether these cognitions are associated with emotional symptoms, maladaptive coping, and functional impairment, as predicted by the cognitive-behavioral model. Method: A total of 35 adult participants with ADHD, 20 nonclinical controls, and 20 non-ADHD clinical controls were assessed with measures of ADHD symptoms, dysfunctional cognitions, depression and anxiety symptoms, coping strategies, and quality of life. Results: ADHD group showed elevated scores of dysfunctional cognitions relative to nonclinical control group and comparable with clinical control group. Dysfunctional cognitions were strongly associated with emotional symptoms. ADHD group also showed elevated scores in maladaptive coping strategies of the escape-avoidance type. Life impairment was satisfactorily predicted in data analysis when ADHD symptoms, dysfunctional cognitions, and emotional symptoms were fitted into a regression model. Conclusion: Cognitive-behavioral therapy model appears to be a valid complementary model for understanding emotional and life impairment in adults with ADHD.

Not Always Hyperactive? Elevated Apathy Scores in Adolescents and Adults With ADHD

Objectives: To investigate the presence of apathy symptoms in adolescents and adults with ADHD as a behavioral manifestation of underlying motivational deficits and to determine whether apathy symptoms were associated with a specific neuropsychological profile. Method: A total of 38 ADHD participants (28 of the combined subtype [ADHD/C] and 10 of the inattentive subtype [ADHD/I]) and 30 healthy controls (Ctrl) were assessed on two measures of apathy administered to subjects and informants. As well, ADHD participants completed a comprehensive neuropsychological battery. Results: ADHD participants presented elevated scores on measures of apathy relative to controls (ADHD/I > ADHD/C > Ctrl). Informant-based ratings of apathy correlated significantly with behavioral measures of inattention. Apathy measures correlated significantly with executive tests, working memory, verbal fluency, and general intellectual abilities, only in the inattentive sample. Conclusions: This study stresses the relevance of motivational deficits in adult ADHD as a significant clinical dimension closely linked to inattention and executive difficulties.

Personality changes in dementia: are they disease specific and universal?

Previous studies about personality changes in dementia suggest that they may be due to the disruption of the biological basis of personality traits, and hence, that they are disease specific and universal. However, evidence about its specificity is still limited and scarce regarding culturally diverse populations. Accordingly, our aim was to compare personality changes in Argentinean patients with Alzheimer disease, behavioral variant of frontotemporal dementia, and primary progressive aphasia. The closest living relatives of patients diagnosed with Alzheimer disease (n=19), behavioral variant of frontotemporal dementia (n=16), and primary progressive aphasia (n=15) were asked to complete 2 versions of the personality inventory NEO Personality Inventory-Revised, one for assessing patients’ premorbid personality traits, and the other for assessing current traits. All groups showed changes in several domains and facets of the NEO Personality Inventory-Revised. Globally, the observed pattern of changes was fairly consistent with previous studies based on the same model of personality. Nevertheless, our results regarding disease-specificity were less conclusive. Even if there were some indicators of specific differences between groups, most traits varied similarly across the 3 groups, revealing a pattern of generalized changes in personality expression after illness onset. More studies are needed that help to distinguish real personality changes from other affective or cognitive symptoms that accompany dementia, as well as further data from culturally diverse populations.

Approximations to an Integrated Model of Eating Disorders and Muscle Dysmorphia among University Male Students in Argentina

Male body dissatisfaction has been associated with drive for muscularity and, in extreme cases, with the clinical condition referred to as muscle dysmorphia (MD). Although recent research suggests that MD is closely linked to eating disorders (EDs), it is classed as a subtype of body dysmorphic disorder. A cross-sectional study was conducted among 402 university male students in Buenos Aires to examine common factors in the development of EDs and MD. Multiple regression analyses were performed to assess the predictive value of the investigated variables. For both conditions, the models accounted for 48 percent of the variance and were predicted by a similar set of variables. The results support the inclusion of MD within the EDs spectrum.