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N M Docherty

Publications and source records attributed to N M Docherty.

30 records · Page 2Linked to original sources
PubMed1996

Affective reactivity of symptoms as a process discriminator in schizophrenia.

Evidence from naturalistic and laboratory studies indicates that schizophrenic symptoms are exacerbated by stress or arousal of negative affect in some patients and not in others. Affective reactivity of symptoms may reflect a pathophysiological process or set of processes present only in a subset of cases of schizophrenia and, therefore, may constitute a dimension potentially relevant to subtyping efforts aimed at discriminating separate processes within the disorder. This paper reviews the evidence a) that affective reactivity of symptoms exists in some but not all schizophrenic patients, b) that this dimension corresponds with other variables that also are putative process discriminators, and c) that it is associated with a more global pathological reactivity to sensory and affective stimuli. Hypotheses as to its biological substrata, relevance to treatment, and importance to larger diagnostic issues are discussed.

Affect↗
PubMed1995

Abnormal laterality in schizophrenics and their parents.

Previous studies found that schizophrenics do not show the normal right ear-left hemisphere perceptual advantage on language-related dichotic tests of lateralized cerebral function. We report evidence of a similar abnormality in non-schizophrenic parents of schizophrenic patients. Perceptual asymmetry was first measured with a dichotic word test which had previously yielded differences between schizophrenics and controls. The parents (n = 18) demonstrated a lower right ear advantage (REA) than controls (n = 10) (p = 0.05), but performed similarly to their schizophrenic offspring (n = 10). The same subjects were given two additional tests. Neutral words were paired with words of a positive emotional valence in one test, and with words of a negative emotional valence in the other. On these two tests, the parents were more similar to the controls than to their offspring with the schizophrenics demonstrating a lower REA than their parents (p = 0.005) on the negative test. These results suggest that schizophrenics and their parents have similar abnormalities in hemispheric activation at baseline only, but when listening to words with negative emotional valence, only the schizophrenics demonstrate a further decrease in left hemispheric activation.

Adult↗
PubMed1995

Linguistic reference performance in parents of schizophrenic patients.

Clinicians have often reported observing subtle signs of thought disorder or communication difficulties in parents of schizophrenic patients. Ascertaining empirically whether these impressions are valid and, if so, clarifying the nature of such disturbances is important for at least two reasons. First, it could assist in elucidating the etiologies of the illness. If distinguishing parental characteristics could be clearly defined, then further research could be undertaken to determine to what extent they represent genetic vulnerability markers, pathogenic environmental influences, or behavioral responses to having a disordered offspring. Secondly, it could facilitate our understanding of the cognitive processes involved in schizophrenia or in the constitutional vulnerability to schizophrenia.

Adult↗
PubMed1995

Expressed emotion and language disturbances in parents of stable schizophrenia patients.

Nineteen healthy parents of long-term schizophrenia outpatients were assessed for levels of expressed emotion (EE) and for characteristics of communication style which are putative markers of vulnerability to schizophrenia. We administered measures of communication deviance, linguistic reference performance, global disorganization, and positive formal thought disorder. Parents high in EE showed significantly poorer linguistic reference performance and greater disorganization in their speech than parents low in EE. These findings support the idea that high EE in some individuals may be associated with cognitive characteristics indicative of a vulnerability to schizophrenia, and this may account in part for the well-established association between EE level in parents and prognosis in patients.

Adult↗
PubMed1994

Affective reactivity of language in schizophrenia.

Thirty acutely schizophrenic inpatients each provided two speech samples: one on affectively negative, "high-stress" topics and one on affectively positive, "low-stress" topics. We analyzed these using two different, established methods for assessment of deviance in natural language, including clinical measures of thought disorder and linguistic measures of reference performance. For the group as a whole, the speech on negative topics contained more disorder than did the speech on positive topics, as rated both clinically and linguistically, and these differences were sizeable and highly significant. Level of language disturbance and degree of affective reactivity of language symptoms correlated positively with severity of the positive syndrome but were not associated in either direction with negative syndrome severity. Affective reactivity of symptoms is discussed as a variable potentially relevant to studies of psychophysiology and subtyping in schizophrenia.

Adult↗
PubMed1994

Affective reactivity of language in stable schizophrenic outpatients and their parents.

We assessed levels of communication disturbance by counting the frequency of unclear linguistic references in the speech of 10 stable schizophrenic outpatients, 18 of their "unaffected" parents, and 10 nonpsychiatric controls, in affectively negative versus affectively positive conditions. Patient and parent groups scored approximately equally on the reference performance measure in the positive condition, and significantly more poorly than controls. Patients' speech deteriorated significantly in the negative condition, while parents' and controls' speech did not. The degree to which patients' speech was reactive to negative affect corresponded to the severity of their core positive symptoms of delusions and hallucinations. Poor reference performance in parents predicted poor performance and a more severe history of positive symptoms in their patient offspring. These data support the hypothesis that poor reference performance represents a vulnerability marker for schizophrenia, and that affective reactivity of language symptoms is associated with an underlying positive schizophrenic process.

Adult↗
PubMed1994

Cognitive characteristics of the parents of schizophrenic patients.

This article reviews the empirical literature on cognition and communication in the parents of schizophrenic patients to address the questions of whether these parents as a group show evidence of any distinguishing cognitive characteristics and, if so, what those characteristics might be. Included in the review are studies of thought and communication disorder, and psychometric studies of cognitive functioning. We included only those that used reliable measures and included control groups in their designs. Taken together, the findings provide substantial evidence that nonschizophrenic parents of schizophrenic patients as a group demonstrate subtle cognitive difficulties in the area of concept formation and maintenance. There are also indications of other cognitive anomalies that will require further study. We discuss the importance of clarifying the etiological relevance of these findings and of pursuing further research in this area.

Attention↗
PubMed1993

Communication deviance, attention, and schizotypy in parents of schizophrenic patients.

Singer and Wynne's measures of communication deviance were adapted for use with conversational speech and applied to audiotaped speech samples of schizophrenic patients, their parents, and matched nonpsychiatric control subjects. The parents demonstrated levels of language disturbance similar to those of the patients and higher than those of controls. Language deviance in the parents was positively associated with distractibility on a matched-task digit-span measure of attention and with severity scores on a separate schizotypy scale. These findings are discussed with respect to possible cognitive variables underlying the language disturbances and their potential relevance to schizophrenic etiology.

Adult↗
PubMed1990

Cognitive deficits and thought disorder: II. An 8-month followup study.

Schizophrenic (n = 21) and manic (n = 19) patients were followed up an average of 8 months after an index assessment during an acute admission. These patients were tested at both assessments with laboratory tasks measuring distractibility and reality monitoring and were examined with clinical ratings of positive and negative thought disorder. For manic patients, none of the measures predicted the patients' clinical state of followup, while negative thought disorder, although rare, was temporally stable. For the schizophrenic patients, both negative thought disorder and distractibility were temporally stable, and more severe negative thought disorder was found at index assessment in patients who were psychotic at followup. The differential utility of laboratory and clinical indices for the prediction of overall clinical state is related to these data.

Adult↗
PubMed1990

Development and preliminary validation of a questionnaire assessment of expressed emotion.

A questionnaire for management of expressed emotion was constructed. It consisted of two scales, criticism and emotional overinvolvement. The questionnaire and the Camberwell Family Interview were then administered to relatives of schizophrenics and preliminary assessments of scale reliabilities and concurrent validities were done. Both questionnaire scales were reliable. With respect to validity the criticism scale correctly classified 88% of the subjects relative to the criticism scale of the interview. The emotional overinvolvement scale was less satisfactory (67%) but still assisted in classification of over-all expressed emotion. Expressed emotion, classification by the questionnaire, correctly identified 84% of the subjects with respect to the interview.

Adult↗
PubMedDate not supplied

Communication disturbances in schizophrenia: a two-process formulation.

We hypothesized that communication disturbances in the form of unclear linguistic references in schizophrenia are associated with excess-related pathophysiologic processes in some individuals and deficit-related processes in others. We divided a sample of 28 acutely ill schizophrenic inpatients into two groups: those with negative symptoms and those without. We analyzed audiotaped speech samples from each subject, and found that the two groups did not differ significantly on overall level of communication disturbance. In patients without negative symptoms, level of communication disturbance was associated with severity of positive symptoms (r = .62, P < .02) and with neuroleptic responsiveness (r = .52, P < .06 [trend]). In those with negative symptoms, level of communication disturbance did not correlate with severity of positive symptoms (r = .09, NS), and correlated negatively with medication responsiveness (r = -.66, P < .01). These findings support a two-process hypothesis of schizophrenic communication disturbance.

Acute Disease↗