Nicole R. Karcher

Examining Associations Between Psychosis Risk, Social Anhedonia, and Performance of Striatum-Related Behavioral Tasks

Both psychosis and anhedonia have been associated to some extent with striatal functioning. The current study examined whether either psychosis risk or social anhedonia was associated with performance on 3 tasks related to striatal functioning. Psychosis risk participants had extremely elevated Perceptual Aberration/Magical Ideation (PerMag) scores (n = 69), with 43% of psychosis risk participants also having semistructured interview-assessed psychotic-like experiences which further heightens their risk of psychotic disorder (Chapman, Chapman, Kwapil, Eckblad, & Zinser, 1994). Compared with both extremely elevated social anhedonia (n = 60) and control (n = 68) groups, the PerMag group exhibited poorer performance on 2 of the striatum-related tasks, the Weather Prediction Task (WPT) and the Learned Irrelevance Paradigm, but not on Finger Tapping. In addition, PerMag participants with psychotic-like experiences were especially impaired on the WPT. Overall, this study arguably provides the first evidence that psychosis risk but not social anhedonia is associated with performance on the WPT, a task thought to be strongly associated with activation in the associative striatum, and also suggests that the WPT might be especially useful as a behavioral measure of psychosis risk.

Sex Differences in Magical Ideation: A Community-Based Twin Study

Two questions regarding sex differences in magical ideation were investigated in this study: (1) whether there are mean-level sex differences on the Magical Ideation Scale (MIS), and (2) whether there are quantitative and/or qualitative sex differences in the genetic contributions to variation on this scale. These questions were evaluated using data obtained from a large community sample of adult Australian twins (N = 4,355) that included opposite-sex pairs. Participants completed a modified 15-item version of the MIS within a larger assessment battery. Women reported both higher means and variability on the MIS than men; this was also observed within families (in opposite-sex twin pairs). Biometric modeling indicated that the proportion of variation in MIS scores due to genetic influences (indicating quantitative sex differences) and the specific latent genetic contributions to this variation (indicating qualitative sex differences) were the same in men and women. These findings clarify the nature of sex differences in magical ideation and point to avenues for future research.

Associations between Electrophysiological Evidence of Reward and Punishment-Based Learning and Psychotic Experiences and Social Anhedonia in At-Risk Groups.

Both positive psychotic symptoms and anhedonia are associated with striatal functioning, but few studies have linked risk for psychotic disorders to a neural measure evoked during a striatal dopamine-related reward and punishment-based learning task, such as a reversal learning task (RLT; Cools et al, 2009). The feedback-related negativity (FRN) is a neural response that in part reflects striatal dopamine functioning. We recorded EEG during the RLT in three groups: (a) people with psychotic experiences (PE; n=20) at increased risk for psychotic disorders; (b) people with extremely elevated social anhedonia (SocAnh; n=22); and (c) controls (n=20). Behaviorally, consistent with increased striatal dopamine, the PE group exhibited better behavioral learning (ie, faster responses) after unexpected reward than after unexpected punishment. Moreover, although the control and SocAnh groups showed a larger FRN to punishment than reward, the PE group showed similar FRNs to punishment and reward, with a numerically larger FRN to reward than punishment (with similar results on these trials also found for a P3a component). These results are among the first to link a neural response evoked by a reward and punishment-based learning task specifically with elevated psychosis risk.

Emotional word usage in groups at risk for schizophrenia-spectrum disorders: An objective investigation of attention to emotion

Both extreme levels of social anhedonia (SocAnh) and extreme levels of perceptual aberration/magical ideation (PerMag) indicate increased risk for schizophrenia-spectrum disorders and are associated with emotional deficits. For SocAnh, there is evidence of self-reported decreased trait positive affect and abnormalities in emotional attention. For PerMag, there is evidence of increased trait negative affect and increased attention to negative emotion. Yet, the nature of more objective emotional abnormalities in these groups is unclear. The goal of this study was to assess attention to emotions more objectively in a SocAnh, PerMag, and control group by using a positive (vs. neutral) mood induction procedure followed by a free writing period. Linguistic analyses revealed that the SocAnh group used fewer positive emotion words than the control group, with the PerMag group falling in between the others. In addition, both at-risk groups used more negative emotion words than the control group. Also, for the control group only, those in the positive mood induction used more positive emotion words, suggesting their emotions influenced their linguistic expression. Overall, SocAnh is associated with decreased positive emotional expression and at-risk groups are associated with increased negative emotional expression and a decreased influence of emotions on linguistic expression.

An electrophysiological investigation of emotional abnormalities in groups at risk for schizophrenia-spectrum personality disorders

Both extreme levels of social anhedonia (SocAnh) and perceptual aberration/magical ideation (PerMag) are associated with risk for schizophrenia-spectrum disorders and with emotional abnormalities. Yet, the nature of any psychophysiological-measured affective abnormality, including the role of automatic/controlled processes, is unclear. We examined the late positive potential (LPP) during passive viewing (to assess automatic processing) and during cognitive reappraisal (to assess controlled processing) in three groups: SocAnh, PerMag, and controls. The SocAnh group exhibited an increased LPP when viewing negative images. Further, SocAnh exhibited greater reductions in the LPP for negative images when told to use strategies to alter negative emotion. Similar to SocAnh, PerMag exhibited an increased LPP when viewing negative images. However, PerMag also exhibited an increased LPP when viewing positive images as well as an atypical decreased LPP when increasing positive emotion. Overall, these results suggest that at-risk groups are associated with shared and unique automatic and controlled abnormalities.

Evidence that communication impairment in schizophrenia is associated with generalized poor task performance

People with schizophrenia exhibit wide-ranging cognitive deficits, including slower processing speed and decreased cognitive control. Disorganized speech symptoms, such as communication impairment, have been associated with poor cognitive control task performance (e.g., goal maintenance and working memory). Whether communication impairment is associated with poorer performance on a broader range of non-cognitive control measures is unclear. In the current study, people with schizophrenia (n =51) and non-psychiatric controls (n =26) completed speech interviews allowing for reliable quantitative assessment of communication impairment. Participants also completed multiple goal maintenance and working memory tasks. In addition, we also examined (a) simple measures of processing speed involving highly automatic prepotent responses and (b) a non-cognitive control measure of general task performance. Schizophrenia communication impairment was significantly associated with poor performance in all cognitive domains, with the largest association found with processing speed (rs =-0.52). Further, communication impairment was also associated with the non-cognitive control measure of poor general task performance (rs =-0.43). In contrast, alogia, a negative speech symptom, and positive symptoms were less if at all related to cognitive task performance. Overall, this study suggests that communication impairment in schizophrenia may be associated with relatively generalized poor cognitive task performance.

An Experimental Examination of the Aberrant Salience Hypothesis Using a Salience Manipulation and a Behavioral Magical Thinking Task

A prominent hypothesis of delusions is that they reflect aberrant salience caused by increased striatal dopamine. For the first time, we conducted an experimental test of the aberrant salience hypothesis (n = 235 college students) as we manipulated salience and examined its effect on magical thinking (using a behavioral task). We also included a putative dopamine manipulation (performing a high reward or low reward task). Both the salience and the putative dopamine manipulations caused changes in magical thinking. Evidence supporting the validity of the magical thinking behavioral task included that it was associated with self-reported magical thinking and with another behavioral task (reversal learning) previously associated with striatal dopamine. In a manipulation check, the putative dopamine manipulation also caused altered performance on the reversal learning task. Overall, these results seem to be consistent with the predictions of the aberrant salience hypothesis and are potentially consistent with a role for salience and dopamine in magical thinking.

Ethical and Legal Issues Addressing the Use of Mobile Health (mHealth) as an Adjunct to Psychotherapy

mHealth refers to the rapidly evolving use of mobile devices for health care treatment purposes, particularly the use of apps and texting as adjuncts to psychotherapy. Although there is currently an extensive literature on issues related to telehealth, to date little guidance has been developed to help professionals function ethically in the rapidly emerging area of mHealth. This article identifies the major ethical considerations that need attention and proposes several recommendations to address mHealth use as an adjunct to psychotherapy, including the pressing need for relevant American Psychological Association practice guidelines to assist mental health providers in the ethical implementation of mHealth.

Probabilistic Category Learning and Striatal Functional Activation in Psychosis Risk

BACKGROUND Psychosis risk is associated with striatal dysfunction, including a previous behavioral study that found that psychosis risk is associated with impaired performance on a probabilistic category learning task (PCLT; ie, the Weather Prediction Task), a task strongly associated with striatal activation. The current study examined whether psychosis risk based on symptom levels was associated with both poor behavioral performance and task-related physiological dysfunction in specific regions of the striatum while performing the PCLT. METHODS There were 2 groups of participants: psychosis risk (n = 21) who had both (a) extreme levels of self-reported psychotic-like beliefs and experiences and (b) interview-rated current attenuated psychotic symptoms (APS); and a comparison group (n = 20) who had average levels of self-reported psychotic-like beliefs and experiences. Participants completed the PCLT during fMRI scanning. RESULTS The current research replicated previous work finding behavioral PCLT deficits at the end of the task in psychosis risk. Furthermore, as expected, the psychosis risk group exhibited decreased striatal activation on the task, especially in the associative striatum. The psychosis risk group also displayed decreased activation in a range of cortical regions connected to the associative striatum. In contrast, the psychosis risk group exhibited greater activation predominantly in cortical regions not connected to the associative striatum. CONCLUSIONS Psychosis risk was associated with both behavioral and striatal dysfunction during performance on the PCLT, suggesting that behavioral and imaging measures using this task could be a marker for psychosis risk.

Genetic Predisposition vs Individual-Specific Processes in the Association Between Psychotic-like Experiences and Cannabis Use

Importance Previous research indicates that cannabis use is associated with psychotic-like experiences (PLEs). However, it is unclear whether this association results from predispositional (ie, shared genetic) factors or individual-specific factors (eg, causal processes, such as cannabis use leading to PLEs). Objectives To estimate genetic and environmental correlations between cannabis use and PLEs, and to examine PLEs in twin and nontwin sibling pairs discordant for exposure to cannabis use to disentangle predispositional from individual-specific effects. Design, Setting, and Participants In this cross-sectional analysis, diagnostic interviews and self-reported data were collected from 2 separate population-based samples of twin and nontwin sibling pairs. Data from the Human Connectome Project were collected between August 10, 2012, and September 29, 2015, and data from the Australian Twin Registry Cohort 3 (ATR3) were collected between August 1, 2005, and August 31, 2010. Data were analyzed between August 17, 2017, and July 6, 2018. The study included data from 1188 Human Connectome Project participants and 3486 ATR3 participants, totaling 4674 participants. Main Outcomes and Measures Three cannabis-involvement variables were examined: frequent use (ie, ≥100 times), a DSM-IV lifetime cannabis use disorder diagnosis, and current cannabis use. Genetic and environmental correlations between cannabis involvement and PLEs were estimated. Generalized linear mixed models examined PLE differences in twin and nontwin sibling pairs discordant for cannabis use. Results Among the 4674 participants, the mean (SD) age was 30.5 (3.2) years, and 2923 (62.5%) were female. Data on race/ethnicity were not included as a covariate owing to lack of variability within the ATR3 sample; among the 1188 participants in the Human Connectome Project, 875 (73.7%) were white. Psychotic-like experiences were associated with frequent cannabis use (&bgr; = 0.11; 95% CI, 0.08-0.14), cannabis use disorder (&bgr; = 0.13; 95% CI, 0.09-0.16), and current cannabis use (&bgr; = 0.07; 95% CI, 0.04-0.10) even after adjustment for covariates. Correlated genetic factors explained between 69.2% and 84.1% of this observed association. Within discordant pairs of twins/siblings (Npairs, 308-324), Psychotic-like experiences were more common in cannabis-exposed individuals compared with their relative who used cannabis to a lesser degree (&bgr; ≥ .23, P < .05; eg, frequent and infrequent cannabis-using relatives significantly differed, z = −5.41; P < .001). Conclusions and Relevance Despite the strong contribution of shared genetic factors, frequent and problem cannabis use also appears to be associated with PLEs via person-specific pathways. This study’s findings suggest that policy discussions surrounding legalization should consider the influence of escalations in cannabis use on traitlike indices of vulnerability, such as PLEs, which could contribute to pervasive psychological and interpersonal burden.