Factor analysis of the Communication Disturbances Index.

The present study utilized factor analysis to investigate possible underlying processes in schizophrenic thought disorder. Using the Communication Disturbances Index [CDI; Arch. Gen. Psychiatry, 53, (1996) 358], a measure of disruption in the communication of meaning from speaker to listener, we examined the speech of 58 stable schizophrenia outpatients for six different types of referential communication disturbances. We calculated instances of disturbance per 100 words and then factor-analyzed our data using the SAS statistical package. Principal components analysis with an oblique rotation produced both a two- and a three-factor solution, depending on factor inclusion criteria. In the three-factor solution, the first two factors reflected weaknesses in language structural organization and in concept-boundary definition, respectively. The third factor appeared to reflect weaknesses in specific facets of memory functioning. In the two-factor solution, the aforementioned structural organization and concept-boundary definition factors were combined into a single executive functioning factor. Results from the study may be heuristic in the development of models of language disturbance in schizophrenia patients.

Conceptual sequencing and disordered speech in schizophrenia.

This study examined associations between impairments of attention, memory, and conceptual sequencing ability, and specific schizophrenia thought and language symptoms. Speech samples of stable schizophrenia outpatients were assessed for frequencies of six different types of communication failures. The classification of types of failures was based on hypothesized differences in underlying cognitive process. Frequencies of the four types of communication failures believed to involve language structural weaknesses all were significantly and fairly strongly related to conceptual sequencing ability. In addition, regression analyses indicated that each of these four types of communication failures was associated with a unique configuration of attentional, memorial, and conceptual sequencing processes. In contrast, the two types of communication disturbances not suggestive of language structural problems were not positively associated with any of the cognitive weaknesses assessed.

Immediate memory, attention and communication disturbances in schizophrenia patients and their relatives.

BACKGROUND: Schizophrenia has been defined in part by disturbances of thought and language. The non-schizophrenic relatives of patients also have been found to show subtle disturbances of language that may be associated with vulnerability. Investigators have hypothesized that these phenomena in patients and their relatives are, at least in part, the result of weaknesses in facets of attention and memory. METHODS: The present study assessed some neuropsychological process correlates of three different measures of thought and language symptoms in 55 stable out-patients, using tests of immediate auditory memory impairment and auditory distractability, and carefully controlling for generalized deficit effects. A parallel assessment was made of referential communication disturbances in 59 non-schizophrenic relatives of patients and 24 control subjects matched to the relatives. RESULTS: In patients, formal thought disorder, disorganization, and referential communication disturbances were all associated with each other and with auditory distractability. In addition, as expected, referential communication disturbances were associated with immediate auditory memory impairment. Referential disturbance ratings for relatives were similar in magnitude to those for the stable out-patients, and much higher than for controls. However, the relatives' language ratings were not associated specifically with weaknesses in attention or memory as measured. CONCLUSIONS: Impairments in immediate auditory memory and attention are associated differentially with different types of communication disturbances in schizophrenia patients. The cognitive substrate for referential communication disturbances in relatives appears to differ qualitatively from that for patients.

Communication disturbances in relatives beyond the age of risk for schizophrenia and their associations with symptoms in patients.

This article provides a detailed examination of subclinical disturbances in the natural speech of healthy relatives beyond the age of risk for schizophrenia. Speech samples from 43 stable schizophrenia outpatients, 42 nonschizophrenia parents of patients (pairs only), and 23 control subjects matched to the parents were analyzed for frequencies of six specific types of communication failures. The parents had higher overall communication disturbance ratings than the control subjects. The specific types of failures that occurred more frequently were unclarities caused by (1) language structural breakdown, (2) use of vague, overinclusive words, and (3) use of words with ambiguous meanings. In intrafamilial analyses, higher levels of communication disturbance in parents were associated with greater severity of illness in their patient offspring. These results support the idea that communication disturbances may be one manifestation of a stable genetic vulnerability to schizophrenia. The nature of the failures identified suggests the possible involvement of weaknesses in specific areas of cognitive functioning.

Communication disturbances and family psychiatric history in parents of schizophrenic patients.

Parents of schizophrenic patients have demonstrated subtle disturbances of thought, language, and communication. The etiologic relevance of these disturbances is not clear. This study assessed levels of referential communication disturbance in the "natural speech" of schizophrenic patients, nonschizophrenic parents of patients, and control subjects matched to the patients' parents and tested for associations of communication disturbances in parents with family history of psychosis and with schizotypy scale scores. The speech of the patients' parents as a group contained high frequencies of referential failures. Those parents with first-degree family histories of psychosis and/or high schizotypy scale scores made more frequent referential failures than the rest of the parents. Family history was particularly highly associated with failures involving language structural breakdown. The results of this study suggest that referential disturbances in parents of patients may be related to genetic liability in the parents. However, such an effect does not appear to account fully for the sizable differences between parents and controls in levels of communication disturbance.

Affective reactivity of speech in schizophrenia patients and their nonschizophrenic relatives.

This study compared levels of referential communication disturbance in speech samples from 41 stable schizophrenia outpatients, 46 parents of patients, and 23 nonpsychiatric control participants in affectively positive versus affectively negative conditions. The speech of the patients and parents showed elevated frequencies of reference failures in the affectively positive condition compared with control participants: the speech of the patients became more disordered in the affectively negative condition, whereas the speech of the parents did not. These results support the idea that referential communication disturbances reflect vulnerability, as well as overt illness, but that affective reactivity of these disturbances is associated mainly with the manifest illness. These findings are consistent with biological, cognitive, and psychological theories about the processes underlying stress responsiveness of schizophrenic symptoms more generally.