Auditory verbal hallucinations (AVHs) in schizophrenia have been suggested to arise from failure of corollary discharge mechanisms to correctly predict and suppress self-initiated inner speech. However, it is unclear whether such dysfunction is related to motor preparation of inner speech during which sensorimotor predictions are formed. The contingent negative variation (CNV) is a slow-going negative event-related potential that occurs prior to executing an action. A recent meta-analysis has revealed a large effect for CNV blunting in schizophrenia. Given that inner speech, similar to overt speech, has been shown to be preceded by a CNV, the present study tested the notion that AVHs are associated with inner speech-specific motor preparation deficits.

The present study aimed to provide a useful framework for directly testing the long-held idea that AVHs may be related to inner speech-specific CNV blunting in patients with schizophrenia. This may hold promise for a reliable biomarker of AVHs.

Hallucinating (n=52) and non-hallucinating (n=45) patients with schizophrenia, along with matched healthy controls (n=42), participated in a novel electroencephalographic (EEG) paradigm. In the Active condition, they were asked to imagine a single phoneme at a cue moment while, precisely at the same time, being presented with an auditory probe. In the Passive condition, they were asked to passively listen to the auditory probes. The amplitude of the CNV preceding the production of inner speech was examined.

Healthy controls showed a larger CNV amplitude (p = .002, d = .50) in the Active compared to the Passive condition, replicating previous results of a CNV preceding inner speech. However, both patient groups did not show a difference between the two conditions (p > .05). Importantly, a repeated measure ANOVA revealed a significant interaction effect (p = .007, ηp2 = .05). Follow-up contrasts showed that healthy controls exhibited a larger CNV amplitude in the Active condition than both the hallucinating (p = .013, d = .52) and non-hallucinating patients (p < .001, d = .88). No difference was found between the two patient groups (p = .320, d = .20).

The results indicated that motor preparation of inner speech in schizophrenia was disrupted. While the production of inner speech resulted in a larger CNV than passive listening in healthy controls, which was indicative of the involvement of motor planning, patients exhibited markedly blunted motor preparatory activity to inner speech. This may reflect dysfunction in the formation of corollary discharges. Interestingly, the deficits did not differ between hallucinating and non-hallucinating patients. Future work is needed to elucidate the specificity of inner speech-specific motor preparation deficits with AVHs. Overall, this study provides evidence in support of atypical inner speech monitoring in schizophrenia.

None Declared

Adolescents with depression have distinct affective reactions to daily events, but current research is controversial. The emotional context insensitivity theory suggests blunted reactivity in depression, whereas the hypotheses of negative potentiation and mood brightening effect suggest otherwise. While nonlinear associations between depression severity and affective reactivity have been observed, studies with a separate subclinical group remain rare. Subthreshold depression (SD), defined by two to four symptoms lasting for two weeks or more, provides a dimensional view to the underpinnings of affective reactivity. In this study, we compared positive affect (PA) and negative affect (NA) reactivity to positive and negative daily events (uplifts and stress) among adolescents with Major Depressive Disorder (MDD), SD and healthy controls (HC) using experience sampling methods (ESM).

We hypothesized a stepped difference in affective reactivity along the depression spectrum: the MDD group will have the strongest reactivity of PA and NA to uplifts and stress, followed by SD and HC.

Three groups (MDD, SD, and HC) of adolescents were recruited from an epidemiologic sample entitled ‘Hong Kong Child and Adolescent Psychiatric Epidemiologic Survey: Age 6 to 17’. Group status was determined by the Diagnostic Interview Schedule for Children Version 5. They completed an experience sampling diary on smartphone for 14 consecutive days, with 5-10 entries per day. Momentary levels of PA (happy, relaxed, contented), NA (irritated, low, nervous), uplifts and stress experienced before the entry were measured on a 1-7 Likert scale.

The sample consisted of 19 adolescents with MDD, 30 with SD, and 59 HC. The M:F ratio was 17:19. The age range was 12-18 with a mean of 14.8. The overall ESM completion rate was 46%. The MDD group had the highest levels of stress and NA, and the lowest levels of uplifts and PA, followed by the SD and HC groups respectively (p<0.01). Across groups, levels of PA were positively associated with uplifts and negatively associated with stress, whereas levels of NA were positively associated with stress and negatively associated with uplifts. The Group x Uplift interaction effect on PA was significant, with greater PA reactivity in SD (p<0.01) and MDD (p=0.07) when compared with HC. The Group x Uplift interaction effect on NA was significant, with greater NA reactivity in SD than HC (p<0.01). The Group x Stress interaction effect on PA was significant, with greater PA reactivity in SD than HC (p<0.01) and MDD (p<0.01). The Group x Stress interaction effect with NA is non-significant.

Contrary to our hypothesis, adolescents with SD experienced strongest PA and NA reactivity in uplifts and PA reactivity in stress. It provides evidence towards a nonlinear relationship between severity of depression and affective reactivity.

None Declared

Heightened affective responses to daily life stressors, referred to as elevated affective reactivity to stress (or ‘stress sensitivity’), have been proposed as a putative mechanism of schizophrenia. Previous studies on stress sensitivity mainly used a case-control design; given that schizophrenia is heterogeneous its relationship with specific symptoms (e.g. paranoia) is yet to be addressed. In view of the continuum approach of understanding psychotic symptoms, the relationship between stress sensitivity (especially ‘social stress sensitivity’) and paranoia in the general population is important. Supported by emerging evidence of the relationship between hostile attribution bias (i.e. a tendency to interpret others’ actions as hostile and intentional) and paranoia, we hypothesized that social stress sensitivity mediates the relationship between hostile attribution bias and momentary experiences of paranoia.

Using experience sampling method, this study aimed to examine the association between social stress sensitivity, hostile attribution bias and momentary paranoia in non-clinical young adults. We also tested the role of social stress sensitivity as mediator of the relationship between hostile attribution bias and momentary paranoia.

Consented participants free from any past and current psychiatric diagnoses (confirmed with the Structured Clinical Interview for DSM-IV Disorders) completed the measure of hostile attribution bias (i.e. abbreviated Ambiguous Intentions Hostility Questionnaire). Participants then filled in an ESM questionnaire measuring momentary levels of paranoia, social stress (i.e. pleasantness of and preference for being alone or with others) and negative affect on a mobile phone app repeatedly, ten times per day over six days. Social stress reactivity was calculated as the within-moment correlation between social stress and negative affect. The associations between social stress sensitivity, hostile attribution bias and momentary paranoia, and the mediating role of social stress sensitivity, were tested with multilevel modelling.

The final sample consisted of 131 participants (57.3% female, mean age= 20.36 (SD= 2.93)). The mean compliance rate was 71.9% (SD= 0.16). Social stress sensitivity was positively associated with momentary paranoia (B= 0.03, p= .002). Hostile attribution bias was associated with momentary paranoia (B= 0.41, p< .001), as well as social stress reactivity (B= 0.10, p= .003). The mediating effect from hostile attribution bias to momentary paranoia via social stress sensitivity was significant (ab= 0.05, 95% CI [0.03-0.07]).

Social stress sensitivity was related to momentary paranoia, as well as hostile attribution bias. Our finding suggests social stress reactivity as a potential mechanism underlying the relationship between hostile attribution bias and paranoia.

None Declared

Despite evidence on the short-term benefits of early intervention (EI) service for psychosis, long-term outcome studies are limited by inconsistent results. This study examined the 10-year outcomes of patients with first-episode psychosis who received 2-year territory-wide EI service compared to those who received standard care (SC) in Hong Kong using an historical control design.

Consecutive patients who received the EI service between 1 July 2001 and 30 June 2002, and with diagnosis of schizophrenia-spectrum disorders, were identified and matched with patients who received SC first presented to the public psychiatric service from 1 July 2000 to 30 June 2001. In total, 148 matched pairs of patients were identified. Cross-sectional information on symptomatology and functioning was obtained through semi-structured interview; longitudinal information on hospitalization, functioning, suicide attempts, mortality and relapse over 10 years was obtained from clinical database. There were 70.3% (N = 104) of SC and 74.3% (N = 110) of EI patients interviewed.

Results suggested that EI patients had reduced suicide rate (χ2(1) = 4.35, p = 0.037), fewer number [odds ratio (OR) 1.56, χ2 = 15.64, p < 0.0001] and shorter duration of hospitalization (OR 1.29, χ2 = 4.06, p = 0.04), longer employment periods (OR −0.28, χ2 = 14.64, p < 0.0001) and fewer suicide attempts (χ2 = 11.47, df = 1, p = 0.001) over 10 years. At 10 years, no difference was found in psychotic symptoms, symptomatic remission and functional recovery.

The short-term benefits of the EI service on number of hospitalizations and employment was sustained after service termination, but the differences narrowed down. This suggests the need to evaluate the optimal duration of the EI service.