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Alex S Cohen

Publications and source records attributed to Alex S Cohen.

14 recordsLinked to original sources
PubMed2006

Neuropsychology of the deficit syndrome: new data and meta-analysis of findings to date.

The deficit syndrome is thought to characterize a pathophysiologically distinct subgroup of patients with schizophrenia. Supporting this notion, prior research examining the neuropsychological correlates of the deficit syndrome has suggested the presence of a differential impairment in frontal and parietal functions. This article reports findings from 2 studies attempting to replicate and extend previous reports of a differential neuropsychological impairment in deficit schizophrenia. In the first study, we administered a comprehensive neuropsychological battery to 20 deficit and 25 nondeficit patients with schizophrenia and 25 normal healthy controls. In the second study, a meta-analysis was conducted of 13 separate studies examining the neuropsychology of the deficit syndrome. There was little evidence from either of the present studies that the deficit syndrome is associated with a selective impairment in frontal and parietal lobe functions. The first study failed to find significant differences in frontal or parietal abilities for deficit vs nondeficit patients. The meta-analytic findings revealed that deficit patients were globally more neuropsychologically impaired than nondeficit patients (effect size [ES] = 0.41). Relative to nondeficit patients, deficit patients performed poorest on tests of olfaction (ES = 1.11), social cognition (ES = 0.56), global cognition (ES = 0.52), and language (ES = 0.51). The neuropsychological impairments associated with the deficit form of schizophrenia do not follow an obvious anatomically defined pattern of impairment. The question of whether deficit patients exhibit a unique cognitive impairment profile will require a more sophisticated and rigorous examination of the neuropsychology of the deficit syndrome.

Adult↗
PubMed2006

Neuropsychological functioning and social anhedonia: results from a community high-risk study.

Social anhedonia has shown promise as a vulnerability marker for schizophrenia-spectrum pathology. Validity data have come, in part, from findings indicating that cognitive deficits occurring in schizophrenia are also evident in individuals with elevated levels of social anhedonia. However, prior research on this topic has been limited because it has been based almost exclusively on the study of selective samples of college students. The present article reports baseline findings of neuropsychological functioning in social anhedonics and controls from a representative community sample. Data on a wide array of neuropsychological abilities from 18-19 year-old participants with (n = 85) vs. without (n = 87) elevated levels of social anhedonia were analyzed. We hypothesized that, compared to controls, social anhedonics would show impairments in memory and sustained attention. Additionally, we sought to determine if more severe cognitive impairment in anhedonics was associated with greater schizophrenia-spectrum pathology and poorer overall functioning. Compared to controls, socially anhedonic participants performed more poorly on two visual-spatial memory tasks and a test of visual-spatial construction. The groups did not statistically differ on any of the other neuropsychological measures including general cognitive ability and sustained attention. Group differences were not the result of depression, bipolar or substance abuse disorders. Neuropsychological functioning showed little relationship to current clinical symptoms and functioning. Longitudinal assessment of these participants as they move through the risk period should provide important insights into the neuropsychological correlates of the schizophrenia prodrome.

Adult↗
PubMed2006

Attentional dysfunction, social perception, and social competence: what is the nature of the relationship?

The aim of this study was to examine the nature of the relationship between attentional dysfunction and social competence deficits in patients with schizophrenia. Attentional functioning, social perception, and social competence were assessed in 56 inpatients. Measures of vigilance and span of apprehension were administered to assess attentional functioning. Social perception was assessed with an audiovisual measure of affect recognition. Social competence was rated from a role-play task. Span of apprehension and auditory vigilance emerged as specific predictors of social competence. Affect recognition was tested as a mediator and a moderator of the relationship between attentional dysfunction and social competence. Affect recognition was found to moderate the relationship between span of apprehension and social competence.

Adult↗
PubMed2005

Specific cognitive deficits and differential domains of social functioning impairment in schizophrenia.

There is considerable inconsistency in findings regarding the relationship between specific cognitive deficits and social impairment in patients with schizophrenia. This inconsistency may relate to variability across studies in how social functioning is measured and preliminary evidence suggests that different indices of social functioning (e.g., laboratory test, community assessment) may have different cognitive correlates. The present study examined this issue by evaluating the relationships between cognitive deficits (including social cognitive deficits), role-play test performance, and community social functioning in 28 inpatients with schizophrenia. We expected the two measures of social functioning to have only modest convergence with each other. Moreover, informed by the literature on cognitive functioning in schizophrenia, we identified specific cognitive processes that were hypothesized to be associated with role-play performance (delayed verbal memory and attentional vigilance) and social functioning in the community (delayed verbal memory and executive functioning). As expected, the two measures of social functioning were modestly correlated with each other. Community social functioning was associated with a relatively constrained pattern of cognitive deficits and received a significant contribution (Deltar2=0.24) from specific cognitive processes beyond that of general cognitive functioning and symptom severity. In contrast to our hypotheses, role-play test performance was associated with a wide range of cognitive impairments and received little contribution from the specific cognitive processes beyond the effects of general cognitive functioning. Community social functioning, but not role-play test performance, was significantly associated with social cognition. These findings highlight the importance of conceptualizing social functioning as a multidimensional construct for schizophrenia research.

Adult↗
PubMed2005

The structure of negative symptoms within schizophrenia: implications for assessment.

This review examines the structural validity of negative symptoms focusing on 2 questions: (1) Do negative symptoms represent a domain separate from other symptoms in schizophrenia? and (2) Within negative symptoms, is there a structure that suggests multidimensionality? Results from exploratory and confirmatory factor analytic studies are examined to address these questions. Across studies and symptom instruments, negative symptoms appear to consistently emerge as a factor separate from other dimensions of the illness in schizophrenia. Whether 2-, 3-, or 5-factor models are identified, negative symptoms consistently load on a factor separate from positive symptoms, affective symptoms of depression or anxiety, and symptoms of disorganization. Focusing on negative symptoms themselves, factor analytic findings suggest that this construct is multidimensional with at least 2 factors (involving diminished expression and anhedonia-asociality). Although these factors were replicable, serious limitations were noted in this literature. Thus, 2- (or even 3- or 5-) factor models of negative symptoms should not be considered definitive, but rather all converge to support the general conclusion of the multidimensionality of negative symptoms. The later findings indicate the importance of employing assessments that provide adequate coverage of the broad domain of negative symptoms. Importantly, caution is noted in the interpretability of findings based on existing instruments, and implications for future assessment are discussed.

Factor Analysis, Statistical↗
PubMed2005

Effects of positive affect on speech disorder in schizophrenia.

Speech disorder exacerbates when negative affect is aroused in patients with schizophrenia. However, little is known about the effects of positive affect on speech disorder. A well-validated laboratory procedure was used to determine whether arousal of positive affect would modulate speech disorder in 57 stable outpatients with schizophrenia and 48 community controls. Overall, the level of speech disorder modulation was negligible for both groups, although there was considerable variability in whether patients' speech disorder exacerbated or ameliorated. Results suggest that arousal of positive affect has an ameliorative effect on speech disorder for certain patients who have relatively severe symptomatology.

Adult↗
PubMed2005

Diminished emotionality and social functioning in schizophrenia.

There is indirect evidence to suggest that a subgroup of patients with schizophrenia exhibit a diminished capacity to experience both positive and negative emotions. To date however, no studies have focused specifically on this diminished emotionality (DE). The main objective of the present project was to determine whether patients with self-reported DE differed from other patients in level of social functioning, physical and social anhedonia, and negative/deficit symptoms. Seventy-three state hospital patients with DSM-IV diagnosed schizophrenia and 22 nonpsychiatric controls were examined. Results provided mixed support for the present hypotheses. Patients with self-reported DE (N = 10) versus those without (N = 63) had poorer social functioning, similar levels of physical and social anhedonia, and significantly less severe negative/deficit symptoms. Moreover, there was a substantial amount of discrepancy between patients' self-reported levels of emotionality and the ratings of their emotionality as made by trained observers. Implications of these results are discussed.

Adult↗
PubMed2005

Symptom-oriented versus syndrome approaches to resolving heterogeneity of neuropsychological functioning in schizophrenia.

Schizophrenia is a heterogeneous disorder. The syndrome and the symptom-oriented approaches are two methods that have been used to examine differences in psychopathological processes across different patients with schizophrenia. The authors indirectly compared these two approaches in their examination of associations between positive symptoms and neuropsychological performance. Positive syndrome and delusion and hallucination severity scores were compared in respective associations to functioning on 12 neuropsychological variables in 73 stable outpatients with schizophrenia. The individual symptoms of the positive syndrome were associated with relatively distinct patterns of neuropsychological performance, suggesting that the symptom-oriented approach was more sensitive.

Adolescent↗
PubMed2004

Stress and arousability in schizophrenia.

This paper examines trait arousability (TA), a temperament characteristic, in 47 stable outpatients with schizophrenia and 50 non-psychiatric controls. Self-reported levels of stress were obtained during a negative and positive memory speech task. Levels of TA, and the association of TA scores with reported stress during the speech tasks, were examined both between and within groups. In addition, TA scores were examined in relation to symptom presentation in the patient group. Patients reported higher levels of trait arousability and higher levels of stress than controls. Trait arousability scores were significantly associated with reported stress in one of the speech condition in patients, and with the severity of positive and affective symptoms. These results suggest that temperament characteristics of an individual with schizophrenia may be related to stress responsiveness and symptom presentation.

Adult↗
PubMed2004

Affective reactivity of speech and emotional experience in patients with schizophrenia.

Communication disturbances are exacerbated by stress in patients with schizophrenia, a phenomenon known as affective reactivity of speech. However, a subset of these patients, those with the deficit syndrome, is characterized by a diminished capacity to experience emotion. We examined affective reactivity in the natural speech of schizophrenia patients with and without the deficit syndrome, with the expectation that deficit syndrome patients would evidence lower levels of affective reactivity. Two 10-min conversational speech samples were collected from each of 13 deficit syndrome patients, 22 nondeficit patients and 26 healthy control subjects. One speech sample from each participant was on the topic of emotionally negative, stressful memories, and the other was on emotionally positive, nonstressful memories. The audiotaped speech samples were analyzed blindly for frequencies of referential communication failure. All three groups showed significantly higher frequencies of communication disturbances in the emotionally negative speech sample than the positive speech sample. Nondeficit patients showed greater affective reactivity of speech than either deficit patients or controls. Conversely, deficit patients' speech was not more reactive to emotion than the speech of the control group. These results suggest that emotion-related variables mediate the relationship between stress and language symptom exacerbations in at least some patients with schizophrenia.

Adult↗
PubMed2004

Deficit versus negative syndrome in schizophrenia: prediction of attentional impairment.

Findings on neuropsychological associates of the negative syndrome of schizophrenia have been inconsistent. The "deficit syndrome," a reconceptualization of the negative syndrome, was developed in part to address this inconsistency. The purpose of this study was (1) to replicate previous findings relating the deficit syndrome to impairment of certain kinds of attentional abilities, and (2) to compare the negative and deficit syndromes in their associations with performance on tests of attention. Data from 40 individuals with schizophrenia were analyzed. Results provide evidence to suggest that impairment of certain attentional processes is associated with severity of deficit symptomatology, while impairment of other attentional processes is not. Moreover, the negative and deficit syndromes differed in their respective associations with attentional task performance at a trend level or above for five of seven tasks, suggesting that the negative and deficit syndromes do indeed have different underlying neuropsychological correlates.

Adult↗
PubMed2003

Stability of formal thought disorder and referential communication disturbances in schizophrenia.

This study examined the degree to which different types of communication disturbances in the speech of 48 schizophrenia patients and 28 controls were variable and state related versus stable and traitlike. Clinically rated formal thought disorder and 5 types of referential disturbance showed substantial stability within participants over time. The sixth type of referential disturbance, the vague reference, was not stable over time. Formal thought disorder was associated with the severity of core psychotic symptoms in patients. whereas referential disturbances showed little or no association with positive or negative symptom severity. Furthermore, changes in psychotic symptoms over time were accompanied by corresponding changes in formal thought disorder but not referential disturbances. These results support the idea that some types of referential disturbances are traitlike and may be reflective of vulnerability as well as manifest illness.

Adolescent↗
PubMed2003

Self-reported stress and the deficit syndrome of schizophrenia.

GENERALLY speaking, schizophrenia is not associated with diminished positive and negative emotions. Even patients with negative symptoms such as blunted affect have generally not differed in their levels of self-reported emotionality compared to patients without negative symptoms. However, there is evidence to suggest that a subgroup of patients with negative symptoms, those with the deficit syndrome, have a diminished capacity to experience positive and negative emotions. The present study examined whether ratings of the deficit and negative syndrome were associated with lower levels of self-reported stress during a laboratory-based, emotion-induction manipulation. Thirty-six participants with schizophrenia were asked to produce separate affectively positive and affectively negative narratives. Immediately following each narrative, participants were asked to report the level of stress they had experienced while recounting their memories. The deficit syndrome ratings, analyzed in a continuous and a categorical manner, were associated with lower levels of self-reported stress in the affectively negative condition. Moreover, the deficit and negative syndrome ratings significantly differed in their associations to levels of self-reported stress during both tasks, supporting the notion that there are appreciable differences between the two syndromes. Given that stress has been an essential component in conceptualizations of schizophrenia onset and relapse, the possibility of stress-resistant properties associated with the deficit syndrome should be tested in future research.

Adult↗