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Introduction: Suboptimal effort-based decision-making with reduced willingness to expend effort for high-probability/high-value reward is observed in schizophrenia patients and is related to diminished motivation, but is understudied in schizotypy. This study aimed to examine effort-allocation in schizotypy individuals and its association with amotivation and psychosocial functioning. Methods: We recruited 40 schizotypy individuals and 40 demographically-matched healthy controls, based on Schizotypal Personality Questionnaire-Brief (SPQ-B) score (top and bottom 10% SPQ-B scores, respectively), from 2400 young people aged 15-24 years participating a population-based mental health survey in Hong Kong and examined effort-allocation using the Effort Expenditure for Reward Task (EEfRT). Negative / amotivation symptoms and psychosocial functioning were assessed by the Brief Negative Symptom Scale (BNSS) and the Social Functioning and Occupational Assessment Scale (SOFAS), respectively. Schizotypy individuals were categorized into high-amotivation and low-amotivation groups based on a median-split of BNSS amotivation domain score. Results: Our results showed no main group effect (in either two or three-group comparison) on effort task performance. Three-group comparison analyses on selected EEfRT performance indices revealed that high-amotivation schizotypy individuals displayed significantly less increase in effortful options from low-value to high-value reward (reward-difference score) and from low-probability/low-value to high-probability/high-value reward (probability/reward-difference score) than low-amotivation individuals and controls. Correlation analyses demonstrated trend-wise significance between BNSS amotivation domain score and several EEfRT performance indices in schizotypy group. Schizotypy individuals with poorer psychosocial functioning tended to exhibit smaller probability/reward-difference score relative to other two groups. Discussion: Our findings indicate subtle effort-allocation abnormalities in schizotypy individuals with high levels of diminished motivation, and suggest the link between laboratory-based effort-cost measures and real-world functional outcome.
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BACKGROUND: Previous research has shown the relationship between loneliness and affect, as well as the relationship between trait loneliness and state loneliness. However, none has investigated how social context affects the association between loneliness and affect. The current study aims to examine the association between trait loneliness, state loneliness and momentary affects in different social contexts. METHODS: Participants aged 15-24 were randomly recruited from a Hong Kong epidemiological study to participate in an Experience Sampling Method (ESM) study. The group was divided in two based on the mean trait loneliness score (UCLA Loneliness Scale) at baseline. State loneliness, momentary positive (PA) and negative affect (NA) and social context were assessed using ESM. Multilevel logistic regression was used to analyze the association between momentary affect, state loneliness and trait loneliness in various social contexts. RESULTS: HL (high lonely) and LL (low lonely) groups consisted of 79 participants (44.6%) and 98 participants (55.4%) respectively. HL group had lower PA and higher NA, as well as a higher state loneliness than LL group. HL group had a lower state loneliness when being with intimate company compared to alone. LL group only had a higher PA when being with intimate company compared to non-intimate company and alone respectively. CONCLUSION: Adolescents with high level of trait loneliness experienced higher PA, momentary loneliness and lower NA compared to those with low level of trait loneliness. The quality of social company is crucial in allowing one to experience different degrees of PA and momentary loneliness.
