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

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 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

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

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

Sample characteristics by sex for study variables.

<p>Sample characteristics by sex for study variables.</p

Associations between salivary serotonin levels and psychological measures.

<p>(A) The scatterplot demonstrates the negative correlation between salivary serotonin levels and perspective taking (<i>n</i> = 182). (B) The scatterplot demonstrates the negative correlation between salivary serotonin levels and happiness rating scores in the self-positive/friend-positive condition (<i>n</i> = 183).</p

Results of the questionnaire.

<p>The bar graph shows happiness rating scores as a function of the participants’ emotional valence (positive, neutral, or negative) and the situation of a friend (absent, positive, or negative). Each column and the error bars represent means ± standard errors (<i>n</i> = 212).</p

Results from the regression analysis examining the association between salivary serotonin and perspective taking.

<p>Results from the regression analysis examining the association between salivary serotonin and perspective taking.</p

Results from the regression analysis examining the association between salivary serotonin and happiness in self-positive/friend-positive condition.

<p>Results from the regression analysis examining the association between salivary serotonin and happiness in self-positive/friend-positive condition.</p