Alexander Genevsky

Motivation and its Relationship to Neurocognition, Social Cognition, and Functional Outcome in Schizophrenia

OBJECTIVE A burgeoning area of research has focused on motivational deficits in schizophrenia, producing hypotheses about the role that motivation plays in the well-known relationship between neurocognition and functional outcome. However, little work has examined the role of motivation in more complex models of outcome that include social cognition, despite our increased understanding of the critical role of social cognition in community functioning in schizophrenia, and despite new basic science findings on the association between social cognitive and reward processing in neural systems in humans. Using path analysis, we directly contrasted whether motivation 1) causally influences known social cognitive deficits in schizophrenia, leading to poor outcome or 2) mediates the relationship between social cognitive deficits and outcome in this illness. METHOD Ninety one patients with schizophrenia or schizoaffective disorder completed interview-based measures of motivation and functional outcome as well as standardized measures of neurocognition and social cognition in a cross-sectional design. RESULTS In line with recent research, motivation appears to mediate the relationship between neurocognition, social cognition and functional outcome. A model with motivation as a causal factor resulted in poor fit indicating that motivation does not appear to precede neurocognition. CONCLUSIONS Findings in the present study indicate that motivation plays a significant and mediating role between neurocognition, social cognition, and functional outcome. Potential psychosocial treatment implications are discussed, especially those that emphasize social cognitive and motivational enhancement.

Timing is everything: Neural response dynamics during syllable processing and its relation to higher-order cognition in schizophrenia and healthy comparison subjects

Successful linguistic processing requires efficient encoding of successively-occurring auditory input in a time-constrained manner, especially under noisy conditions. In this study we examined the early neural response dynamics to rapidly-presented successive syllables in schizophrenia participants and healthy comparison subjects, and investigated the effects of noise on these responses. We used magnetoencephalography (MEG) to reveal the time-course of stimulus-locked activity over bilateral auditory cortices during discrimination of syllable pairs that differed either in voice onset time (VOT) or place of articulation (POA), in the presence or absence of noise. We also examined the association of these early neural response patterns to higher-order cognitive functions. The M100 response, arising from auditory cortex and its immediate environs, showed less attenuation to the second syllable in patients with schizophrenia than healthy comparison subjects during VOT-based discrimination in noise. M100 response amplitudes were similar between groups for the first syllable during all three discrimination conditions, and for the second syllable during VOT-based discrimination in quiet and POA-based discrimination in noise. Across subjects, the lack of M100 attenuation to the second syllable during VOT-based discrimination in noise was associated with poorer task accuracy, lower education and IQ, and lower scores on measures of Verbal Learning and Memory and Global Cognition. Because the neural response to the first syllable was not significantly different between groups, nor was a schizophrenia-related difference obtained in all discrimination tasks, early linguistic processing dysfunction in schizophrenia does not appear to be due to general sensory input problems. Rather, data suggest that faulty temporal integration occurs during successive syllable processing when the signal-to-noise ratio is low. Further, the neural mechanism by which the second syllable is suppressed during noise-challenged VOT discrimination appears to be important for higher-order cognition and provides a promising target for neuroscience-guided cognitive training approaches to schizophrenia.

Evidence for an emotion maintenance deficit in schizophrenia

Research has indicated that people with schizophrenia have deficits in reward representation and goal-directed behavior, which may be related to the maintenance of emotional experiences. Using a laboratory-based study, we investigated whether people with schizophrenia were able to maintain an emotional experience when given explicit instructions to do so. Twenty-eight people with schizophrenia and 19 people without completed a behavioral task judging their emotional experience of pictures held over a three second delay. This emotion maintenance task was compared to a subsequent in-the-moment emotion experience rating of each picture. In addition, all participants completed an analogous brightness experience maintenance and rating task, and patients completed a standardized visual working memory task. Participants with schizophrenia showed normal in-the-moment emotion experience of the emotion pictures; however, they showed decreased performance on emotion maintenance (for both positive and negative emotion) compared to participants without schizophrenia, even after controlling for brightness maintenance. The emotion maintenance deficit was not associated with visual brightness performance nor with performance on the visual working memory task; however, negative emotion maintenance was associated with an interview-based rating of motivation. These findings suggest that some aspects of impaired emotion maintenance in schizophrenia may be related to deficits in motivated behavior.

Neural Affective Mechanisms Predict Market-Level Microlending

Humans sometimes share with others whom they may never meet or know, in violation of the dictates of pure self-interest. Research has not established which neuropsychological mechanisms support lending decisions, nor whether their influence extends to markets involving significant financial incentives. In two studies, we found that neural affective mechanisms influence the success of requests for microloans. In a large Internet database of microloan requests (N = 13,500), we found that positive affective features of photographs promoted the success of those requests. We then established that neural activity (i.e., in the nucleus accumbens) and self-reported positive arousal in a neuroimaging sample (N = 28) predicted the success of loan requests on the Internet, above and beyond the effects of the neuroimaging sample’s own choices (i.e., to lend or not). These findings suggest that elicitation of positive arousal can promote the success of loan requests, both in the laboratory and on the Internet. They also highlight affective neuroscience’s potential to probe neuropsychological mechanisms that drive microlending, enhance the effectiveness of loan requests, and forecast market-level behavior.

Neuroforecasting Aggregate Choice

Advances in brain-imaging design and analysis have allowed investigators to use neural activity to predict individual choice, while emerging Internet markets have opened up new opportunities for forecasting aggregate choice. Here, we review emerging research that bridges these levels of analysis by attempting to use group neural activity to forecast aggregate choice. A survey of initial findings suggests that components of group neural activity might forecast aggregate choice, in some cases even beyond traditional behavioral measures. In addition to demonstrating the plausibility of neuroforecasting, these findings raise the possibility that not all neural processes that predict individual choice forecast aggregate choice to the same degree. We propose that although integrative choice components may confer more consistency within individuals, affective choice components may generalize more broadly across individuals to forecast aggregate choice.