批判に対する統合失調症的認知バイアスの神経基盤

学位の種別:課程博士University of Tokyo(東京大学

Diminished Medial Prefrontal Activity behind Autistic Social Judgments of Incongruent Information

Individuals with autism spectrum disorders (ASD) tend to make inadequate social judgments, particularly when the nonverbal and verbal emotional expressions of other people are incongruent. Although previous behavioral studies have suggested that ASD individuals have difficulty in using nonverbal cues when presented with incongruent verbal-nonverbal information, the neural mechanisms underlying this symptom of ASD remain unclear. In the present functional magnetic resonance imaging study, we compared brain activity in 15 non-medicated adult males with high-functioning ASD to that of 17 age-, parental-background-, socioeconomic-, and intelligence-quotient-matched typically-developed (TD) male participants. Brain activity was measured while each participant made friend or foe judgments of realistic movies in which professional actors spoke with conflicting nonverbal facial expressions and voice prosody. We found that the ASD group made significantly less judgments primarily based on the nonverbal information than the TD group, and they exhibited significantly less brain activity in the right inferior frontal gyrus, bilateral anterior insula, anterior cingulate cortex/ventral medial prefrontal cortex (ACC/vmPFC), and dorsal medial prefrontal cortex (dmPFC) than the TD group. Among these five regions, the ACC/vmPFC and dmPFC were most involved in nonverbal-information-biased judgments in the TD group. Furthermore, the degree of decrease of the brain activity in these two brain regions predicted the severity of autistic communication deficits. The findings indicate that diminished activity in the ACC/vmPFC and dmPFC underlies the impaired abilities of individuals with ASD to use nonverbal content when making judgments regarding other people based on incongruent social information

Aberrant Interference of Auditory Negative Words on Attention in Patients with Schizophrenia

<div><p>Previous research suggests that deficits in attention-emotion interaction are implicated in schizophrenia symptoms. Although disruption in auditory processing is crucial in the pathophysiology of schizophrenia, deficits in interaction between emotional processing of auditorily presented language stimuli and auditory attention have not yet been clarified. To address this issue, the current study used a dichotic listening task to examine 22 patients with schizophrenia and 24 age-, sex-, parental socioeconomic background-, handedness-, dexterous ear-, and intelligence quotient-matched healthy controls. The participants completed a word recognition task on the attended side in which a word with emotionally valenced content (negative/positive/neutral) was presented to one ear and a different neutral word was presented to the other ear. Participants selectively attended to either ear. In the control subjects, presentation of negative but not positive word stimuli provoked a significantly prolonged reaction time compared with presentation of neutral word stimuli. This interference effect for negative words existed whether or not subjects directed attention to the negative words. This interference effect was significantly smaller in the patients with schizophrenia than in the healthy controls. Furthermore, the smaller interference effect was significantly correlated with severe positive symptoms and delusional behavior in the patients with schizophrenia. The present findings suggest that aberrant interaction between semantic processing of negative emotional content and auditory attention plays a role in production of positive symptoms in schizophrenia. (224 words)</p></div

Experimental paradigm.

<p>Participants were asked to selectively attend to either the right- or left-sided voice stimulus within a pair. Then, they were required to select the word heard at the attended ear from four presented candidate words on the screen as quickly as possible. Orthogonally to the task demands, voices could have a semantically different emotional valence, either neutral on both sides, negative (or positive) on the attended side and neutral on the other side, or vice versa, neutral on the attended side and negative (or positive) on the other side.</p

Subject characteristics and symptom scores.

a<p>Socioeconomic status, assessed using the Hollingshead scale. Higher scores indicate lower statu;</p>b<p>Estimated from scores on the Japanese Adult Reading Test;</p>c<p>Assessed using the Edinburgh Inventory. >0 indicates right-handed;</p>d<p>Based on chlorpromazine equivalents;</p>e<p>Positive and Negative Syndrome Scale.</p

Effect of auditory negative words on response time in healthy subjects and patients with schizophrenia.

<p>Response times for Negative-Neutral, Neutral-Negative stimuli on the right-left side were significantly longer than that for Neutral-Neutral word pairs, irrespective of direction of attention in the healthy controls (p = 0.0035, p = 0.025, respectively). In contrast, response time for Positive-Neutral (p = 0.11), Neutral-Positive (p = 0.12) word pairs on the right-left side was not significantly longer than that for Neutral-Neutral word pairs.</p

Aberrant interference of auditory negative words in patients with schizophrenia.

<p>The interference index in patients with schizophrenia was significantly smaller compared with healthy controls when negative words were presented at the right ear, irrespective of attention side (p = 0.025). Because no main effect of Attention-Side and no interaction between Attention-Side and any other factors were found, the means of the interference indices for attending to the right and left ear are presented.</p

Aberrant attentive and inattentive brain activity to auditory negative words, and its relation to persecutory delusion in patients with schizophrenia

Previous research has suggested that deficits in emotion recognition are involved in the pathogenesis of persecutory delusion in schizophrenia. Although disruption in auditory and language processing is crucial in the pathophysiology of schizophrenia, the neural basis for the deficits in emotion recognition of auditorily presented language stimuli and its relation to persecutory delusion have not yet been clarified

Aberrant attentive and inattentive brain activity to auditory negative words, and its relation to persecutory delusion in patients with schizophrenia

Previous research has suggested that deficits in emotion recognition are involved in the pathogenesis of persecutory delusion in schizophrenia. Although disruption in auditory and language processing is crucial in the pathophysiology of schizophrenia, the neural basis for the deficits in emotion recognition of auditorily presented language stimuli and its relation to persecutory delusion have not yet been clarified