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(Reprinted with permission from The American Journal of Psychiatry 2020; 177:868-872)., (Copyright © 2020 by the American Psychiatric Association.)

The nature and definition of schizotypy, as the latent liability for schizophrenia capable of generating various phenotypic and endophenotypic outcomes, is reviewed. The proceedings of the 2017 meeting of the International Consortium on Schizotypy Research are included in this Special Section and they are presented as illustrations of current research work on schizotypy. The potential leverage of the schizotypy framework for schizophrenia research continues to be realized and these articles present current research efforts that explore new angles of inquiry while building upon past advances. Methodological and substantive areas of concern are highlighted and suggestions for improvement of future schizotypy research are made.

Aims: Borderline personality disorder (BPD) is characterized by self-regulation deficits, including impulsivity and affective lability. Transference-focused psychotherapy (TFP) is an evidence-based treatment proven to reduce symptoms across multiple cognitive-emotional domains in BPD. This pilot study aimed to investigate neural activation associated with, and predictive of, clinical improvement in emotional and behavioral regulation in BPD following TFP., Methods: BPD subjects (n = 10) were scanned pre- and post-TFP treatment using a within-subjects design. A disorder-specific emotional-linguistic go/no-go functional magnetic resonance imaging paradigm was used to probe the interaction between negative emotional processing and inhibitory control., Results: Analyses demonstrated significant treatment-related effects with relative increased dorsal prefrontal (dorsal anterior cingulate, dorsolateral prefrontal, and frontopolar cortices) activation, and relative decreased ventrolateral prefrontal cortex and hippocampal activation following treatment. Clinical improvement in constraint correlated positively with relative increased left dorsal anterior cingulate cortex activation. Clinical improvement in affective lability correlated positively with left posterior-medial orbitofrontal cortex/ventral striatum activation, and negatively with right amygdala/parahippocampal activation. Post-treatment improvements in constraint were predicted by pre-treatment right dorsal anterior cingulate cortex hypoactivation, and pre-treatment left posterior-medial orbitofrontal cortex/ventral striatum hypoactivation predicted improvements in affective lability., Conclusions: These preliminary findings demonstrate potential TFP-associated alterations in frontolimbic circuitry and begin to identify neural mechanisms associated with a psychodynamically oriented psychotherapy., (© 2015 The Authors. Psychiatry and Clinical Neurosciences © 2015 Japanese Society of Psychiatry and Neurology.)

Intermittent degradation refers to transient detrimental disruptions in task performance. This phenomenon has been repeatedly observed in the performance data of patients with schizophrenia. Whether intermittent degradation is a feature of the liability for schizophrenia (i.e., schizotypy) is an open question. Further, the specificity of intermittent degradation to schizotypy has yet to be investigated. To address these questions, 92 undergraduate participants completed a battery of self-report questionnaires assessing schizotypy and psychological state variables (e.g., anxiety, depression), and their reaction times were recorded as they did so. Intermittent degradation was defined as the number of times a subject's reaction time for questionnaire items met or exceeded three standard deviations from his or her mean reaction time after controlling for each item's information processing load. Intermittent degradation scores were correlated with questionnaire scores. Our results indicate that intermittent degradation is associated with total scores on measures of positive and disorganized schizotypy, but unrelated to total scores on measures of negative schizotypy and psychological state variables. Intermittent degradation is interpreted as potentially derivative of schizotypy and a candidate endophenotypic marker worthy of continued research.

The concept of schizotypy represents a rich and complex psychopathology construct. Furthermore, the construct implies a theoretical model that has considerable utility as an organizing framework for the study of schizophrenia, schizophrenia-related psychopathology (eg, delusional disorder, psychosis-NOS (not otherwise specified), schizotypal, and paranoid personality disorder), and putative schizophrenia endophenotypes as suggested by Rado, Meehl, Gottesman, Lenzenweger, and others. The understanding (and misunderstanding) of the schizophrenia-related schizotypy model, particularly as regards clinical illness, as well as an alternative approach to the construct require vigilance in order to ensure the methodological approach continues to yield the fruit that it can in illuminating the pathogenesis of schizophrenia-related psychopathology. The articles in the Special Section in this issue of Schizophrenia Bulletin highlight methodological and theoretical issues that should be examined carefully., (© The Author 2015. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

This study compared the performance of 39 biological relatives of persons with schizophrenia to that of 30 normal adult controls on graphesthesia processing, a complex somatosensory processing task. The relatives performed significantly worse on the graphesthesia task compared to the healthy controls. The relatives and control subjects, however, did not differ on two neurocognitive control tasks. These data are interpreted within the context of a somatosensory deficit linked to schizophrenia liability.

Previously, we proposed a theoretical framework that classified infants into qualitative categories of reactivity, rather than on a continuous dimension. The present research used an objective statistical procedure (maximum covariance analysis, or MAXCOV) to determine if a qualitative latent structure, consistent with our theoretical conjectures, would be found to underlie quantitative indices of reactivity to stimuli in a sample of 599 four-month-old infants. Results of the MAXCOV analysis showed clear evidence of a latent discontinuity underlying the behavioral measures of infant reactivity. The base rate of the latent class (or taxon) was estimated at 10%. Infants within the putative high-reactivity taxon, compared with infants not in the taxon, were elevated on measures of behavioral inhibition at 4.5 years. These results provide objective empirical support for a central tenet in our theoretical model by supporting the taxonicity of infant reactivity.

This study examined performance on the Wisconsin Card Sorting Test (WCST) by 23 schizotypic subjects and 28 normal control subjects. Schizotypy was measured on the Perceptual Aberration Scale (PAS). Overall, schizotypic (high PAS) subjects performed more poorly than control (low PAS) subjects on the WCST; specifically, schizotypic subjects showed deficits on the failure-to-maintain-set and number-of-categories indexes. Consistent with expectations based on research with high-risk subjects, schizotypic subjects were nearly 10 times more likely than controls to be included in a subgroup of deviant WCST performers identified by a composite performance index. WCST performance was not associated with current levels of anxiety or depression. Our results provide evidence for subtle WCST performance deficits in subjects hypothesized to be at risk for psychosis--perhaps schizophrenia--and are broadly consistent with current speculation about dorsolateral prefrontal cortex functioning in schizophrenia as well as recent speculation concerning spatial working memory and schizophrenia. The heuristic potential of our results is discussed and we encourage replication of the present study. Viewed in this context, our results are hypothesis-generating and do not provide definitive confirmation of specific hypotheses.

The psychometric high-risk strategy represents a useful methodologic adjunct to the traditional genetic high-risk research approach in the study of the etiology and development of schizophrenia. During the past 15 years, considerable research activity has focused on psychometrically identified individuals hypothesized to be en route to schizophrenia (i.e., putative schizotypes). The Perceptual Aberration Scale (PAS) has figured prominently in such prediction-oriented psychometric high-risk work. This report examines research using the PAS completed since 1987 that has established the instrument as a valid index for detecting liability for schizophrenia (or schizotypy) and as, arguably, the schizotypy index of choice for research. These results are presented and interpreted in light of Meehl's theoretical framework of schizotypy. Other measures of and assessment devices for schizotypy (schizophrenia-related liability) are identified. Of these other measures, the Chapmans' Magical Ideation Scale and the schizophrenia liability index of Moldin and colleagues are particularly well established. Methodologic suggestions for future psychometric high-risk and other work using objective measures of schizotypic psychopathology are offered. It is strongly recommended that future studies of schizotypy (or those in the planning stages, relying on psychometric detection methods use multiple psychometric indices to tap schizotypy or use a psychometric index in association with other promising biobehavioral markers of schizophrenia liability (e.g., sustained attentional deficits, eye movement dysfunction) for maximum efficiency in both location and definition of schizotypes.

The present report examined the latent structure of schizophrenic phenomenology. Schizophrenic patient case histories (n = 192) were rated for positive symptoms, negative symptoms, and premorbid social adjustment and the observed covariation among these clinical features was evaluated using a model-based confirmatory factor analytic approach. Our results indicated that schizophrenic phenomenology was best characterized by three distinct underlying structures. These data provide empirical support for Strauss et al.'s (1974) three-process model, which suggests that positive symptoms, negative symptoms, and disordered premorbid personal-social relationships are three distinct classes of phenomenology possibly reflective of three relatively independent pathological processes in schizophrenia. The data are also consistent with Crow's (1980, 1985, 1987) model of schizophrenic symptomatology, differentiating social impairment from both positive and negative symptoms. The heuristic implications of these data for the development of schizophrenia are discussed and the utility of a replication of the present study is noted.

This study was concerned with the relationship between attentional and information-processing deficits and positive vs. negative symptoms in schizophrenia. Sixteen schizophrenic patients, rated for extent of positive and negative symptomatology, 17 depressed patients, and 31 normal control subjects were tested on a measure of distractibility and ability to process under information overload. To establish the validity of our measures, schizophrenic patients were compared with depressed patients and with normal control subjects. Lowered processing capacity appeared to be specific to schizophrenia, although the specificity of differential distractibility was less clear. For schizophrenic patients, positive symptoms were related to distractibility, whereas negative symptoms were associated with lowered processing capacity. These findings were interpreted as supporting Crow's (1981) hypothesis that the two clinical syndromes reflect independent pathological processes.