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William P Horan

Publications and source records attributed to William P Horan.

At least 19 recordsLinked to original sources
PubMed2006

Social anhedonia and schizotypy: the contribution of individual differences in affective traits, stress, and coping.

While social anhedonia is a promising indicator of vulnerability to schizophrenia, it remains uncertain whether anhedonia is a core feature of schizotypy or merely a secondary associated characteristic. This issue was examined by comparing dimensional scores on schizophrenia spectrum personality disorder symptoms derived from clinical interviews among three groups: a) "pure" social anhedonics with high scores on the Revised Social Anhedonia Scale (SAS; [Eckblad, M.L., Chapman, L.J., Chapman, J.P., Mishlove, M., 1982. The Revised Social Anhedonia Scale. Unpublished test, University of Wisconsin, Madison.]) and low scores on the Magical Ideation Scale (MIS, [Eckblad, M.L., Chapman, L.J., 1983. Magical ideation as an indicator of schizotypy. Journal of Consulting and Clinical Psychology, 51, 215-225.]), b) subjects with high MIS and low SAS scores, and c) controls with low scores on both scales. This study also sought to identify individual differences in stress reactivity, personality, coping style, and social support that might be related to severity of clinical symptoms among at-risk subjects. Compared to controls, the SAS group had higher levels of schizotypal, schizoid, and paranoid symptoms and the MIS group had higher schizotypal symptoms. Among social anhedonics, individual differences in perceived stress, trait negative affectivity, and coping style accounted for over 40% of the variance in schizotypal and paranoid symptoms. This cross-sectional study bolsters support for the validity of social anhedonia as a primary feature of schizotypy. Longitudinal studies are required to determine whether these individual differences potentiate clinical outcomes among social anhedonics.

Adaptation, Psychological↗
PubMed2006

The Consortium on the Genetics of Schizophrenia: neurocognitive endophenotypes.

The Consortium on the Genetics of Schizophrenia (COGS) is a 7-site collaboration that examines the genetic architecture of quantitative endophenotypes in families with schizophrenia. Here we review the background and rationale for selecting neurocognitive tasks as endophenotypic measures in genetic studies. Criteria are outlined for the potential of measures as endophenotypic vulnerability markers. These include association with illness, state independence (ie, adequate test-retest stability, adequate between-site reliability, impairments in patients not due to medications, impairments observed regardless of illness state), heritability, findings of higher rates in relatives of probands than in the general population, and cosegregation within families. The COGS required that, in addition, the measures be "neurocognitive" and thus linked to neurobiology and that they be feasible in multisite studies. The COGS neurocognitive assessment includes measures of attention, verbal memory, working memory, and a computerized neurocognitive battery that also includes facial processing tasks. Here we describe data demonstrating that these neurobehavioral measures meet criteria for endophenotypic candidacy. We conclude that quantitative neurocognitive endophenotypes need further evidence for efficacy in identifying genetic effects but have the potential of providing unprecedented insight into gene-environment interaction related to dimensions of brain and behavior in health and disease.

Cognition Disorders↗
PubMed2006

An analysis of categorical perception of facial emotion in schizophrenia.

BACKGROUND: Emotion perception deficits have been extensively documented in schizophrenia and are associated with poor social functioning. Yet fundamental questions about the nature and scope of these impairments remain unanswered from commonly used experimental tasks. An alternative categorical perception paradigm that focuses on distinguishing boundaries between emotions was used to evaluate whether schizophrenia patients demonstrate atypical patterns of categorical perception and a negativity bias in the identification of ambiguous facial expressions. METHOD: 47 schizophrenia outpatients and 31 nonpsychiatric controls completed a forced-choice emotion identification task. Stimuli consisted of a series of digitized facial images that were morphed in 10% signal intensity increments along continua between pairs of emotions (happy-sad; fearful-happy; angry-fearful; angry-sad) and presented in a random order. For each emotion continuum, measures of the response slope and the location of the boundary shift point between emotions were calculated for each group. RESULTS: The schizophrenia group demonstrated significantly shallower response curves than controls across all emotion continua. Despite these generally less precise demarcations between emotions, patients did not significantly differ from controls in the location of the shift point between emotions on any of the continua. CONCLUSIONS: Schizophrenia patients demonstrated impaired categorical perception of facial expressions with generally less sharp categorizations of ambiguous stimuli to one emotion category or another. However, patients did not demonstrate a negativity bias in their processing of ambiguous facial expressions. The emotional continuum paradigm can help to clarify the nature and boundaries of affect perception deficits in schizophrenia.

Adolescent↗
PubMed2006

Neurocognitive and social cognitive correlates of formal thought disorder in schizophrenia patients.

The neurocognitive and social cognitive correlates of two types of formal thought disorder (i.e., bizarre-idiosyncratic and concrete thinking) were examined in 47 stable outpatients with schizophrenia. Both types of thinking disturbance were related to impairments in verbal learning, intrusions in verbal memory, immediate auditory memory, sustained attention, and social schema knowledge. Distractibility during an immediate memory task was associated with more frequent bizarre verbalizations but not concreteness. Impaired verbal learning rate and intrusions in verbal memory independently contributed to the prediction of bizarre responses, whereas intrusions in verbal memory and impaired immediate memory independently contributed to concrete thinking. This pattern of findings is consistent with the view that neurocognitive and, possibly, social cognitive deficits underlie these two aspects of formal thinking disturbance in schizophrenia.

Adult↗
PubMed2006

Does anhedonia in schizophrenia reflect faulty memory for subjectively experienced emotions?

The authors evaluated whether self-reported trait anhedonia in schizophrenia reflects faulty memory, such that patients are capable of experiencing pleasure while engaged in enjoyable activities but underestimate their pleasure in recalling these experiences. Thirty schizophrenia patients and 31 nonpatient control participants rated their emotional responses to pleasant and neutral foods and film clips and completed a surprise recall task for their emotions after a 4-hr delay. Despite reporting elevated trait anhedonia, patients did not significantly differ from control participants in immediate pleasant emotional responses to the stimuli or in delayed recall for these experiences. In-the-moment pleasure and short-term retention for emotional experiences thus appear to be relatively intact in schizophrenia. Alternative explanations for the hedonic deficit in this disorder are discussed.

Adult↗
PubMed2006

Do recent-onset schizophrenia patients experience a "social network crisis"?

It has been proposed that the onset of schizophrenia creates a social network crisis, resulting in a dramatic deterioration of social resources during the period immediately following a first hospitalization from essentially normal pre-hospitalization levels. To evaluate this proposal, recent onset patients (n = 89) completed comprehensive assessments that examined their social networks in the 12 months prior to first hospitalization and, in a subset of patients (n = 34), at a 15-month follow-up. Cross-sectional relationships to social functioning and symptoms were examined at both time points. Compared to existing research, at the initial assessment patients were characterized by several network disturbances, including small network size, a high proportion of family members, and highly dense interconnections among network members; these disturbances generally remained moderately to highly stable at follow-up. Smaller social networks were related to poor current and premorbid social functioning and aspects of clinical functioning, particularly at the 15-month follow-up assessment. Thus, this first repeated assessment of social network characteristics in the early course of schizophrenia does not support the social network crisis concept. Instead, results suggest that functionally relevant social network disturbances often exist by the time of first hospitalization in schizophrenia.

Adult↗
PubMed2005

Anhedonia in schizophrenia: a review of assessment strategies.

Anhedonia, the diminished capacity to experience pleasant emotions, is a common, treatment-resistant feature of schizophrenia that is often included among the negative symptoms of this disorder. This selective review describes the 3 most commonly used approaches to assess anhedonia in schizophrenia: interview-based measures, self-report trait questionnaires, and laboratory-based assessments of emotional experience. For each assessment approach, psychometric properties, relationships to other symptoms and features of schizophrenia, and relationships with the other assessment approaches are evaluated. It is concluded that anhedonia can be reliably assessed and constitutes a distinctive, clinically important aspect of schizophrenia that should be included in a comprehensive evaluation of negative symptoms. Current efforts to define more precisely the nature of the hedonic deficit in schizophrenia are discussed, and recommendations for optimal assessment of anhedonia in clinical trials of novel treatments for negative symptoms are provided.

Expressed Emotion↗
PubMed2005

Examining the latent structure of negative symptoms: is there a distinct subtype of negative symptom schizophrenia?

Negative symptoms have emerged as a replicable factor of symptomatology within schizophrenia. Although rating scales provide assessments along dimensions of severity, categorization into a negative symptom subtype is typically conducted. A categorical view of negative symptoms is best reflected in the proposal that enduring, primary negative symptoms, or deficit symptoms, reflect a distinct subtype of schizophrenia . Despite an accumulation of findings that support a categorical conceptualization, the data are also consistent with a dimensional-only model where negative symptom subtypologies simply reflect an extreme on a continuum of severity. Using taxometric statistical methods , the present study examined whether a taxonic, or latent class, model best describes negative symptoms in a sample of 238 schizophrenia patients. In order to obtain more stable estimates of symptoms, ratings on the Scale for the Assessment of Negative Symptoms [Andreasen, N.C., 1982. Negative symptoms in schizophrenia: Definition and reliability. Arch. Gen. Psychiatry 39, 784-788.] were averaged across two assessments over a 6-month period. Two taxometric methods, maximum covariance analysis (MAXCOV) and mean above minus below a cut (MAMBAC) identified a latent class or taxon with a base rate of approximately 28-36%. Members of the negative symptom taxon differed from the nontaxon class in that taxon members were more likely to be male and demonstrated poorer social functioning. Taxon and nontaxon schizophrenia patients did not differ in psychotic or affective symptoms. The findings converge to provide support for a categorical view of negative symptoms. Further research is required to replicate the present taxonic findings and to examine characteristics (including possible etiological factors) associated with this negative symptom taxon.

Adult↗
PubMed2005

Stressful life events in recent-onset schizophrenia: reduced frequencies and altered subjective appraisals.

While research strongly supports the notion that stressful life events may trigger the exacerbation of psychotic symptoms in schizophrenia, the mechanisms through which affected individuals respond to life events during the early course of this disorder have received limited attention. This 12-month longitudinal study compared the frequencies, qualitative characteristics, and subjective appraisals of life events in recent-onset schizophrenia patients (n=78) and a nonpatient comparison sample (n=63). Negative and positive life events were assessed using a semi-structured interview every 4 weeks among patients and approximately every 4 months among controls, and participants appraised each event they experienced in terms of emotional impact, controllability, and effectiveness in handling the event. Schizophrenia patients reported significantly lower rates of life events than their nonpsychiatric counterparts across nearly every type of negative and positive event examined. In the context of generally lower event frequencies, patients appraised the negative and positive events they did experience as less controllable and more poorly handled than controls, and also appraised positive events as less desirable. Results are discussed in terms of their implications for understanding susceptibility to stress during the early course of schizophrenia.

Adaptation, Psychological↗
PubMed2005

Schizophrenia patients demonstrate a distinctive pattern of decision-making impairment on the Iowa Gambling Task.

Although dorsolateral prefrontal cortex (DLPFC) abnormalities in schizophrenia are well established, several lines of evidence suggest the orbitofrontal cortex (OFC) may also be dysfunctional in this disorder. We examined the performance of schizophrenia patients and nonpatient controls on the Iowa Gambling Task [Cognition 50 (1994) 7], a decision-making task sensitive to OFC damage that involves a series of selections from four decks of cards that vary in their reward/punishment profiles. Patients also completed neuropsychological tests assessing DLPFC functions and clinical symptom assessments. The schizophrenic patients demonstrated a pattern of impaired performance that differed both from healthy controls and from the "non-conservative" pattern typically found in patients with OFC lesions. The patients selected from the two card decks that had low frequency and high magnitude punishments significantly more often than the decks with high frequency and low magnitude punishments. Performance on the task was not strongly related to tests sensitive to DLPFC dysfunction but was correlated with negative symptoms. Results suggest that individuals with schizophrenia display a pattern of compromised decision-making that is somewhat distinct from that found in OFC lesion patients and that may be linked to certain clinical symptoms.

Adult↗
PubMed2005

Stability and clinical correlates of personality characteristics in recent-onset schizophrenia.

BACKGROUND: While several personality characteristics are implicated in the etiology and phenotypic expression of schizophrenia, little is known about their trait status or clinical correlates during the early course of this disorder. METHOD: The stability of five personality characteristics derived from the MMPI-168 was examined in recent-onset schizophrenia patients (n = 59) during a psychotic period at study entry and at two out-patient assessments over the following 15 months and in non-patient controls (n = 39) at similar time intervals. Among patients, associations between personality characteristics and clinical symptoms and exposure to stressful life events during the study period were also examined. RESULTS: Multilevel modeling analyses indicated that the between-subjects or trait-like variance components for these characteristics among patients were substantial, albeit smaller than those found for controls. Patients reported higher mean levels of Neuroticism, Cynicism, and Psychotic Ideation and lower mean levels of Psychopathic Tendencies and Denial of Somatic Complaints than controls. Among patients, several personality characteristics were systematically related to mean clinical symptom levels as well as frequency of exposure to dependent, but not independent, life events. CONCLUSIONS: Stable individual differences in personality are detectable during the early course of schizophrenia and may help account for heterogeneity in clinical symptoms and functional outcome.

Adult↗
PubMed2004

The timing of negative symptom exacerbations in relationship to positive symptom exacerbations in the early course of schizophrenia.

Although positive and negative symptoms appear to represent independent symptom dimensions of psychopathology when evaluated cross-sectionally among individuals with schizophrenia, it is not known if exacerbations of symptoms on these two dimensions are independent. This prospective longitudinal study examined the temporal relationship between the positive and negative symptom exacerbations among 48 recent-onset schizophrenia or schizoaffective patients who received symptom ratings every 2 weeks on the Brief Psychiatric Rating Scale. Patients were followed for a period of at least 1 year and a mean of 3 years. To examine the temporal relationship between positive and negative symptoms, six time periods were defined in relation to psychotic exacerbation or relapse (e.g., prodromal, concurrent, post-psychotic) and used to compare the timing of positive and negative symptom exacerbations. A substantial proportion of patients had exacerbations of positive symptoms (77%) and negative (42%) symptoms. Negative symptom exacerbations occurred simultaneously with positive symptom exacerbations to a significantly greater extent than expected by chance, and occurred less frequently than expected by chance during the time period most temporally removed from positive symptom exacerbations. Results suggest that the timing of some negative symptom exacerbations is linked to that of positive symptom exacerbations during the early course of schizophrenia.

Adult↗
PubMed2004

Do the siblings of schizophrenia patients demonstrate affect perception deficits?

Affect perception deficits have been extensively documented in schizophrenia and are associated with the social dysfunction that is characteristic of this disorder. The two previous studies examined facial affect perception in genetically at-risk samples and yielded mixed results. The current study was designed to provide a rigorous test of affect perception abilities among schizophrenia patients (n=58), their biological siblings without psychosis (n=51), and nonpsychiatric controls (n=49). Participants completed three measures of affect perception, including facial, vocal, and combined modality. Schizophrenia patients performed significantly worse than controls on two of the three affect perception tests as well as a composite index based on all three tests. The performance of the sibling group fell between the patient and control groups on each of the affect perception tests. However, group differences achieved statistical significance only for the composite index with the siblings performing significantly worse than controls and significantly better than the schizophrenia group. These findings demonstrate that subtle deficits in affect perception are detectable in the unaffected siblings of schizophrenia patients when multiple measures of different types of affect perception abilities are used in combination.

Adult↗
PubMed2004

The psychometric detection of schizotypy: do putative schizotypy indicators identify the same latent class?

The authors examined whether three indicators of Schizotypy, the Revised Social Anhedonia Scale (RSAS), Magical Ideation Scale (MIS), and Perceptual Aberration Scale (PAS), identify a common latent class or taxon as conceptualized by P. E. Meehl (1962, 1990). The separate and joint latent structures of these scales were evaluated using taxometric methods in two large, independent samples. Replicating prior findings, the RSAS and PAS each identified latent taxa with base rates approximating.10. Results for the taxonicity of the MIS were less consistent. Analyses of joint latent structure indicated that the RSAS-identified taxon was essentially independent of constructs measured by the PAS or MIS. Measures commonly thought to tap the same latent class, conjectured to be schizotypy, do not share this property.

Adolescent↗
PubMed2003

Neurocognitive, social, and emotional dysfunction in deficit syndrome schizophrenia.

The deficit syndrome is a promising distinction within schizophrenia that requires further validation. This study examined the replicability of differences in clinical symptoms, neurocognitive functioning, affect perception, and social functioning previously reported among deficit (n=15) and nondeficit syndrome (n=30) schizophrenia patients classified according to the Schedule for the Deficit Syndrome (SDS; Psychiatry Res. 30 (1989) 119) and nonpatient controls (n=41). Additionally, participants completed self-report affective trait measures of positive affectivity, negative affectivity, and social anhedonia to examine the deficit syndrome concept of diminished emotional range. We were able to replicate symptom profiles and neurocognitive and social functioning impairments in deficit vs. nondeficit patients, but did not find more severe affect perception impairment in deficit vs. nondeficit patients as previously reported. Regarding range of subjectively experienced emotion, deficit patients reported lower trait positive affectivity and marginally higher social anhedonia than nondeficit patients and controls, but also reported elevations in negative affectivity that were similar to nondeficit patients as compared to controls. While replication of patterns of impairment across multiple domains of functioning supports the validity of the deficit syndrome, results also suggest that SDS-defined deficit patients may be characterized by a relative reduction in the tendency or ability to experience positive emotions, rather than a pervasive diminution in the range of emotional experience.

Adjustment Disorders↗
PubMed2003

The expression and experience of emotion in schizophrenia: a study of social interactions.

Previous studies on emotional expression and experience in schizophrenia indicate that patients show significantly fewer outward displays of emotion than controls despite similar self-reports of emotional experience in response to various non-social stimuli (e.g. film clips, flavored drinks). However, it is unclear if this disjunction between emotional experience and expression in schizophrenia extends to the interpersonal domain. This study compared 33 patients with schizophrenia and 15 non-psychiatric controls on emotional expression and experience during a social role play. Results showed that patients were significantly less expressive than controls but the two groups reported equal levels of emotional experience. Neither clinical blunting ratings nor behavioral ratings of facial expressivity were related to emotional experience in patients. These results extend prior findings of an expression/experience disjunction in schizophrenia to a social domain. Implications for understanding social dysfunction in schizophrenia and directions for future study are discussed.

Adult↗
PubMed2003

A retrospective study of premorbid ability and aging differences in cognitive clusters of schizophrenia.

This retrospective, cross-sectional study evaluated whether age-related differences in patterns of cognitive deficit exist among four cognitively based schizophrenia subgroups. These subgroups had previously been identified through cluster analyses of a battery of abstraction and problem-solving tests in large samples. Evaluation of estimated premorbid intellectual ability and postmorbid cognitive functioning stratified by decade from the twenties through the fifties revealed different patterns across the schizophrenia subgroups and a clinical comparison sample. A near normal cognitive subgroup demonstrated relatively high premorbid intellectual ability and a pattern of age differences similar to the comparison sample, with the exception of deficits on the Wisconsin Card Sorting Test that were detectable in the twenties and remained stable thereafter. In contrast, a subgroup characterized by severe, pervasive cognitive deficit demonstrated low premorbid intellectual ability and extremely low test scores across the four decades studied. The remaining clusters were characterized by moderate cognitive impairment and showed age differences suggestive of a decline in cognitive function around the time of illness onset that remained stable. Results provide further support for the validity of these subgroups and encourage continued efforts to identify cognitively based candidate schizophrenia subtypes.

Adult↗