Faculty Bibliography

Individuals with schizophrenia display substantial neurocognitive deficits for which available treatments offer only limited benefits. Yet, findings from studies of animals, clinical and nonclinical populations have linked neurocognitive improvements to increases in aerobic fitness (AF) via aerobic exercise training (AE). Such improvements have been attributed to up-regulation of brain-derived neurotrophic factor (BDNF). However, the impact of AE on neurocognition, and the putative role of BDNF, have not been investigated in schizophrenia. Employing a proof-of-concept, single-blind, randomized clinical trial design, 33 individuals with schizophrenia were randomized to receive standard psychiatric treatment (n = 17; "treatment as usual"; TAU) or attend a 12-week AE program (n = 16) utilizing active-play video games (Xbox 360 Kinect) and traditional AE equipment. Participants completed assessments of AF (indexed by VO2 peak ml/kg/min), neurocognition (MATRICS Consensus Cognitive Battery), and serum-BDNF before and after and 12-week period. Twenty-six participants (79%) completed the study. At follow-up, the AE participants improved their AF by 18.0% vs a -0.5% decline in the TAU group (P = .002) and improved their neurocognition by 15.1% vs -2.0% decline in the TAU group (P = .031). Hierarchical multiple regression analyses indicated that enhancement in AF and increases in BDNF predicted 25.4% and 14.6% of the neurocognitive improvement variance, respectively. The results indicate AE is effective in enhancing neurocognitive functioning in people with schizophrenia and provide preliminary support for the impact of AE-related BDNF up-regulation on neurocognition in this population. Poor AF represents a modifiable risk factor for neurocognitive dysfunction in schizophrenia for which AE training offer a safe, nonstigmatizing, and side-effect-free intervention.

Previous research has shown that healthy individuals who fail to differentiate among emotional states (i.e., those with low emotional granularity; EG) have poorer social functioning (SF) than those with high EG. It is unknown, however, whether these associations extend to clinical disorders characterized by impaired SF, such as schizophrenia. In the present study, we compared SF and EG in individuals with schizophrenia and healthy controls, and then, within the schizophrenia group, we examined the links between EG and SF. Employing an Experience Sampling Method approach, 77 individuals with schizophrenia and 27 healthy controls rated their momentary emotions (sadness, anxiety, anger, and happiness) up to 10 times/day over a two-day period using mobile electronic devices. For each participant, we then calculated the within-subject average correlations among the momentary emotion ratings, producing two EG indices - EGIall for all emotions and EGIneg for negative ones. A subsample of participants with schizophrenia also completed self-report, interview, and ability-based measures of SF. Compared to healthy controls, individuals with schizophrenia displayed significantly poorer SF and lower EGIall, but comparable EGIneg. Within the schizophrenia group, hierarchical multiple regression analyses indicated that EGIall, but not EGIneg, significantly predicted social dysfunction after controlling for emotional awareness, symptoms, and emotional intensity and variability. Our findings indicate that individuals with schizophrenia have a relatively intact ability to differentiate among negative emotions in everyday life. However, they experience significant difficulties differentiating between positive and negative emotions, and this may contribute to their social difficulties.