Visual imagery and visual semantics in the cerebral hemispheres in schizophrenia.

Divided visual field tasks were given to normal subjects, and patients with schizophrenia and affective disorder, to investigate hemisphere differences in the visual processing of standardised pictorial stimuli. There were two conditions: in the first, subjects were asked to decide whether a common entity represented by a picture was living or non-living, a task involving a categorical judgement based on semantic information; a left hemisphere task. In the second condition, subjects judged whether these depictions represented entities which were bigger or smaller than a cat; a right hemisphere task requiring visual imagery to compare spatial dimensions. It was found that the patient groups, while showing slower reaction time (RT) overall, both displayed a right hemisphere (RH) advantage on the imagery task. Furthermore, the schizophrenics' RHs showed the normal relationship between closeness of size comparison and RT, additional evidence that the visual imagery mechanism is intact. However, these patients failed to show the expected left hemisphere advantage on the visual-semantic task. There was a suggestion that performance on the semantic task was related to the experience of vivid imagery in normals and visual hallucinations in the schizophrenics. The possible contribution of hemispheric imbalance in the production of visual hallucinations from a disordered semantic system is discussed.

Categorical-semantic and spatial-imagery judgements of non-verbal stimuli in the cerebral hemispheres.

A divided visual field task was given to two groups of normal subjects to investigate hemisphere differences in the processing of standardised pictorial stimuli. There were two conditions: subjects were asked to decide whether an entity represented by a picture was living or non-living, a task involving a categorical judgement based on semantic information, or, in the second condition, whether these depictions represented entities which were bigger or smaller than a cat. This latter task, it is suggested, requires visual imagery to compare spatial dimensions. The first, categorical task produced an LH advantage in reaction time. The second, imagery task, produced an RH advantage provided the comparison involved items whose sizes were relatively close to that of a cat. Furthermore, the size difference was inversely related to reaction time, only when items were presented to the RH. The data obtained are consistent with the notion that there are at least two systems for processing visual information, one specializing in categorical and semantic distinctions related to LH functions, and the other, specialized in spatial coordinates, an aspect of visual imagery, related to the RH.

Semantic and phonological information flow in the production lexicon.

When speakers produce words, lexical access proceeds through semantic and phonological levels of processing. If phonological processing begins based on partial semantic information, processing is cascaded; otherwise, it is discrete. In standard models of lexical access, semantically processed words exert phonological effects only if processing is cascaded. In 3 experiments, speakers named pictures of objects with homophone names (ball), while auditory distractor words were heard beginning 150 ms prior to picture onset. Distractors speeded picture naming (compared with controls) only when related to the nondepicted meaning of the picture (e.g., dance), exhibiting an early phonological effect, thereby supporting the cascaded prediction. Distractors slowed picture naming when categorically (e.g., frisbee) related to the depicted picture meaning, but not when associatively (e.g., game) related to it. An interactive activation model is presented.

Magnetic attraction of gaze: further evidence of hemispheric imbalance in schizophrenia?

A case is reported of a young man with a clinical diagnosis of schizophrenia and unusual oculo-motor abnormalities. The relationship between oculo-motor dysfunction and hemispheric balance in schizophrenia is discussed.

Chronic mania in childhood: case report of a possible association with a radiological picture of cerebellar disease.

The case-history of a woman with psychiatric symptoms since childhood is reported, the best label for which was that of "chronic mania". Cerebellar atrophy was suspected on radiological grounds. The literature on chronic mania in childhood and on cerebellar damage and mental changes is reviewed and the view is put forward that cerebellar dysfunction may play a part in the production of some psychiatric symptoms.

That's the way the cookie bounces: syntactic and semantic components of experimentally elicited idiom blends.

Idioms are sometimes viewed as unitized phrases with interpretations that are independent of the literal meanings of their individual words. In three experiments, the nature of idiom representation was explored with a speech-error elicitation task. In the task, speakers briefly viewed paired idioms. After a short delay they were probed to produce one of the two idioms, and their production latencies and blend errors were assessed. The first experiment showed greater interference between idioms with the same syntactic structure, demonstrating that idiom representations contain syntactic information. The second experiment indicated that the literal meaning of an idiom is active during production. These syntactic and literal-semantic effects on idiom errors argue against a representation of idioms as noncomponential lexicalized phrases. In the final experiment, no differences were found between decomposable and nondecomposable idioms, suggesting that the lexical representation of these two types of idioms is the same.

Affect, affective disorder and schizophrenia. A neuropsychological investigation of right hemisphere function.

Performance on a happy-sad chimeric face test was used to examine the role of right hemisphere activation in positive and negative affect, both normal and abnormal, as well as in schizophrenia. This test is known to elicit a left-sided perceptual bias in right-handed normal subjects. Happy and sad mood in normals did not influence the perceptual bias. Depression and mania were associated with reduced and increased biases respectively, while schizophrenics showed no bias to either side. Possible explanations are right hemisphere hyperfunction in mania, moderate relative hypofunction in depression, and severe relative hypofunction in schizophrenia. The marked difference between mania and schizophrenia supports distinct pathophysiologies underlying the two conditions.

The cocaine experience: refuting the concept of a model psychosis?

Eighteen patients admitted to a drug dependency unit for opiate detoxification and who had recently used cocaine were asked to describe the experience based on a questionnaire. A comparison was made with 18 schizophrenic patients who completed the same questionnaire. Results showed a qualitative difference in the subjective phenomena described by the two groups. There appeared to be certain phenomena present in a cocaine induced state which appear to be specific to this state. Amongst these features are: increased intensity of colours, prominence of certain colours in illusions, i.e. red and green, and changes in light intensity. Objects appear to be more vivid and stand out, macropsia and micropsia also seem to occur in this group and paranoia if present is of a transient nature. These particular symptoms do not seem to be characteristic of a schizophrenic illness. This may therefore contradict the idea of a drug induced psychosis (in this case cocaine) as being indistinguishable from schizophrenia (the model psychosis theory).

Cycloid psychosis: an investigation of the diagnostic concept.

Seventy-three patients with the features of 'cycloid psychosis', adopted from Perris and Leonhard, were identified from case records. Information concerning background, presenting illness and follow-up was compared with that from the case-records of patients with schizophrenic, affective and schizoaffective psychoses. The characteristic features of 'cycloid psychosis' were a female predominance and a remittent course. The 'cycloid' group resembled the conventional groups in some respects, but differences from schizophrenic, affective and, to a lesser extent, schizoaffective groups were also striking. The factors which might account for the apparent independence of the 'cycloid' group from other diagnostic categories are discussed.

Ocular myopathy (progressive external ophthalmoplegia) with neuropathic complications.

The condition known as Ocular Myopathy or Progressive External Ophthalmoplegia is reviewed. Three hundred and thirty-five published case reports have been analyzed and 13 personal cases are described. Histological and electron microscopical studies on one of our cases are reported. It is clear from these cases that, although in its simplest form the condition may consist merely of myopathic changes confined to the upper eyelids and external ocular muscles, myopathic changes may also occur in the muscles of the face, neck and proximal parts of the limbs. In addition, however, a variety of neurological disorders may also develop and degenerative lesions have been found in the peripheral nerves, spinal cord, brain stem, and basal ganglia. Other associated conditions such as perceptive deafness, pigmentary retinal degeneration, cardiomyopathy and red cell abnormalities may also occur. There is thus a wide spectrum of syndromes, all based on a condition which is possibly a general metabolic disorder. Recent work has directed attention to mitochondrial abnormalities in the affected muscle fibers and other cells. A positive family history may be present and an autosomal dominant mode of inheritance seems likely.

The development and use of standardized assessment of abnormal personality.

A standardized assessment of personality (SAP) based on interview with an informant has been developed to classify a patient's premorbid personality in clinical terms for use for research purposes in or out of a hospital setting. Three preliminary investigations of its use are reported. These indicate that an informant's account of personality can be rated reliably by psychiatrists and is consistent over time. The addition of two extra descriptive types to the schema of ICD Section 301, the anxious and the self-conscious personalities, is found to contribute usefully to a taxonomy of personality in two series of patients investigated with the SAP. Further investigations are indicated to determine the accuracy of an informant's account before epidemiological studies with this instrument can be considered.

Some attractions of verb agreement.

In English, words like scissors are grammatically plural but conceptually singular, while words like suds are both grammatically and conceptually plural. Words like army can be construed plurally, despite being grammatically singular. To explore whether and how congruence between grammatical and conceptual number affected the production of subject-verb number agreement in English, we elicited sentence completions for complex subject noun phrases like The advertisement for the scissors. In these phrases, singular subject nouns were followed by distractor words whose grammatical and conceptual numbers varied. The incidence of plural attraction (the use of plural verbs after plural distractors) increased only when distractors were grammatically plural, and revealed no influence from the distractors' number meanings. Companion experiments in Dutch offered converging support for this account and suggested that similar agreement processes operate in that language. The findings argue for a component of agreement that is sensitive primarily to the grammatical reflections of number. Together with other results, the evidence indicates that the implementation of agreement in languages like English and Dutch involves separable processes of number marking and number morphing, in which number meaning plays different parts.

A case of resistant schizophrenia.

In an era when it is generally believed that the acute symptoms of schizophrenia can be controlled pharmacologically, the case of a young man who has remained almost continuously floridly psychotic for 13 years, despite treatment, is disquieting. Conventional psychiatric treatment appears to be rendered impotent. It is in this context that it may be of interest to report a summary of the proceedings of a Special Problems Conference held at the Institute of Psychiatry on 18 February 1985 to discuss such a case.