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Eating disorders in schizophrenia.

An investigation of eating disorders in a population of chronic schizophrenic patients confirmed that there is a distinction between eating disorders of psychotics and eating disorders of the young. All the DSM-III criteria of eating disorders, except one, were observed among the psychotics although no patient fulfilled the necessary criteria for an eating disorder diagnosis except for one anorexic woman. All varieties of schizophrenic eating disorder were reported: in two-fifths of the patients eating disorders were associated with delusions and in one sixth with hallucinations; more than half of the patients had deviant eating behaviour which was not associated with any thought or perceptual disorders. Schizophrenic eating disorders were common, yet not disturbing to the social life of the open mental hospital or to that of the community surrounding it.

Adult↗

[Relationship between years of methamphetamine use and symptoms of methamphetamine psychosis].

The authors researched the demographic characteristics of 233 patients with methamphetamine-associated disorders, and the relation between years of methamphetamine use and symptoms of methamphetamine psychosis. The results were as follows: There were more male users than females. However there were signs that the female users were gradually increasing. Users tended to be older, but users in their 20's and 30's continued to be predominant. Their school careers were usually limited and most of them had left school at a young age. Relations with a particular social group (e.g. organized gangs) has given most of them a chance to use methamphetamine. The symptoms that were seen with high frequency at the first examination were anxiety, fretfulness, auditory hallucination, insomnia, irritability, psychomotor excitement, delusion of persecution, suspicion, delusion of reference, mistake of circumstance, loss of appetite, affective disorder, hypobulia and personality change. With these symptoms, there is a possibility that five years of methamphetamine use is the turning point in terms of the frequency of symptoms occurrence. It was suggested that affective and perceptual disorders depend on the dose of methamphetamine, but abnormalities in thought subject may be deeply influenced by the patient's "feeling of social wrong". Emotional exhilaration and euphoria decreased as the number of years of methamphetamine use increased. These phenomena may be an indication of tolerance. The symptoms that were seen with high frequency at the last examination were hypobulia, affective disorder, personality change, insomnia, anxiety and fretfulness. The symptoms that were highly resistant to treatment were hypobulia, affective disorder, personality change, general malaise, hypochondriasis, insomnia, anxiety and fretfulness. It was suggested that five years of methamphetamine use may be a turning point in the residual rate of symptoms at the last examination after treatment, and also the resistance rate to treatment. Hypobulia and personality change became more evident during treatment.

Adolescent↗

Components in the visual processing of known and unknown faces.

This study investigated the neural basis and cognitive mechanisms of disorders affecting the visual processing of human faces. Two patients affected by prosopagnosia (PA), 45 unilateral brain-damaged patients not previously selected for gnosic disturbance, and 52 normal subjects were administered three tasks involving visual matching of unfamiliar faces, identification of famous faces, and age attribution to unknown faces. Results confirmed that the right hemisphere (and particularly the posterior region) is critical for all of the main aspects of facial processing. Neuroradiological and PET examination in both PA patients revealed a lesion in the territory of the right posterior cerebral artery (infero-mesial areas of temporal and occipital lobes). Moreover, group comparisons showed that patients affected by a right posterior lesion obtained the worst scores on all tasks of our battery. Both group comparisons and single-case analyses pointed out that a deficient recognition of familiar faces is generally independent of perceptual disorders and, as such, should be considered mnestic in nature. Disorders in the age attribution, on the contrary, appear to be strictly associated with deficits in the perceptual analysis of unfamiliar faces.

Aged↗

Reading disabilities and the effects of colored filters.

The efficacy of a controversial treatment, using colored filters to remediate reading disabilities, was measured empirically, with colored overlays placed over reading material on white paper. Irlen's (1983) method is to prescribe specific tinted filters as lenses that she claims filter specific light frequencies and remove a range of perceptual disorders that adversely affect reading and related learning performance. Irlen calls this condition "scotopic sensitivity" and claims it is a significant factor in a high percentage of people with learning disabilities. Ninety-two children with significant reading disabilities were classified as either scotopic or nonscotopic using the Irlen Differential Perceptual Schedule, and were randomly assigned to one of six treatment groups using colored or clear overlays. Reading performance (rate, accuracy, and comprehension) as measured by the Neale Analysis of Reading Ability (Neale, 1987) and the Formal Reading Inventory (Wiederholt, 1986) improved significantly when the scotopic children read with the preferred colored overlay filter compared to clear or different-colored overlay filters. Nonscotopic children showed no change.

Child↗

Auditory temporal processing impairment: neither necessary nor sufficient for causing language impairment in children.

Fourteen twin pairs, aged 8 to 10 years, were tested 3 times over 12 months; they included 11 children with language impairment (LI), 11 control children matched on nonverbal ability and age, and 6 co-twins who did not meet criteria for LI or control status. Thresholds were estimated for detecting a brief backward-masked tone (BM), detection of frequency modulation (FM), and pitch discrimination using temporal cues (deltaf0). Both BM and FM thresholds improved with training, and by the 2nd test session, FM thresholds were in the adult range. There were marked individual differences on BM and deltaf0 and, for both tasks, performance correlated with Tallal's Auditory Repetition Task administered 2 years previously. However, no auditory measure gave significant differences between LI and control groups; performance was influenced more by nonverbal than language ability. Some children did have a stable pattern of poor performance on certain auditory tasks, but their good FM detection raised questions about whether processing of auditory temporal information is abnormal. We found no evidence that auditory deficits are a necessary or sufficient cause of language impairments.

Adult↗

A rating scale for psychotic symptoms (RSPS) part I: theoretical principles and subscale 1: perception symptoms (illusions and hallucinations).

The authors present a new rating scale for the psychotic symptoms of schizophrenia and related psychoses. The scale links specific symptoms of psychopathology to dysfunction and overactivity of dopaminergic mechanisms underlying the processes of reward and selective attention. The Rating Scale for Psychotic Symptoms (RSPS) is a 44-item rating instrument with a seven-point severity scale for each item. Psychotic symptoms are classified into three groups: Pathological amplification of mental images (perception symptoms) (subscale 1), Distraction symptoms (including catatonia and passivity experiences) (subscale 2), and Delusions (subscale 3). A dimensional, rather than a categorical, conceptualization of psychosis is assumed. Rating is accomplished through a manual and a semi-structured interview (SSCI-RSPS). In this first of two papers, general issues about the construction of the scale and the derivation of symptom groups are discussed. Dopamine-mediated modification of cortico-striatal synapses is seen as being of critical importance in all three groups of symptoms. In this first paper, we present subscale I (perception symptoms), which includes both amplified perceptual images (illusions) and hallucinations. A total of seven illusions and 11 hallucinations are rated as individual items.

Behavioral Symptoms↗

[Investigations on the incidence of partial agnosia of sounds (author's transl)].

Stammering as a frequent speech disorder in infancy results from many causes. For instance, it is possible that a child with normal peripheral hearing may be unable to distinguish sounds by tone and therefore will repeat them incorrectly. A testing method is presented in which paired pictures are used which differ by the phonologic opposition of some stammered sounds. The results of the test in 100 children who stammer are reported. Further investigations give evidence that other perceptual disorders can be found in supposed agnosias.

Articulation Disorders↗

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).

Adolescent↗

Visual form perception in deficient and normal readers as a function of age and orthographic-linguistic familiarity.

The present investigation directly assessed the hypothesis that poor readers sustain no basic disorder in visual-spatial functioning. In order to extend pervious results to younger children, the performance of poor and normal readers from both the second and sixth grades was compared. Adopting the format of an earlier investigation, a visual recall task was employed as the dependent variable, and it was predicted that poor readers would perform as well as normals with stimuli taken from Hebrew, an unfamiliar orthography. Accordingly, non-Hebrew poor and normal readers were compared with normal readers learning Hebrew on the production of varying length Hebrew words. As anticipated, children in the non Hebrew reader groups performed comparably on this task, but the performance of these subjects was inferior to that of children in the Hebrew groups. The data support the contention that visual perceptual disorder is an unlikely source of reading disability.

Age Factors↗

Psychometric high-risk paradigm, perceptual aberrations, and schizotypy: an update.

The psychometric high-risk strategy represents a useful methodologic adjunct to the traditional genetic high-risk research approach in the study of the etiology and development of schizophrenia. During the past 15 years, considerable research activity has focused on psychometrically identified individuals hypothesized to be en route to schizophrenia (i.e., putative schizotypes). The Perceptual Aberration Scale (PAS) has figured prominently in such prediction-oriented psychometric high-risk work. This report examines research using the PAS completed since 1987 that has established the instrument as a valid index for detecting liability for schizophrenia (or schizotypy) and as, arguably, the schizotypy index of choice for research. These results are presented and interpreted in light of Meehl's theoretical framework of schizotypy. Other measures of and assessment devices for schizotypy (schizophrenia-related liability) are identified. Of these other measures, the Chapmans' Magical Ideation Scale and the schizophrenia liability index of Moldin and colleagues are particularly well established. Methodologic suggestions for future psychometric high-risk and other work using objective measures of schizotypic psychopathology are offered. It is strongly recommended that future studies of schizotypy (or those in the planning stages, relying on psychometric detection methods use multiple psychometric indices to tap schizotypy or use a psychometric index in association with other promising biobehavioral markers of schizophrenia liability (e.g., sustained attentional deficits, eye movement dysfunction) for maximum efficiency in both location and definition of schizotypes.

Body Image↗

A study of obstruent sounds in school-age children with speech disorders using electropalatography.

In this study EPG was used to investigate the articulatory characteristics of voiceless coronal obstruent targets /s, f, tf, t/ in ten children with functional articulation disorders. Perceptually based judgements of /s, f, tf/ revealed a variety of distortions, including palatal, lateralised and dental articulations. Their productions of /t/ were judged to be acceptable. From the EPG data, it was observed that individual children produced abnormal and often idiosyncratic tongue-palate contact for sounds which were heard as distorted. Some common trends were identified, for example, palatal fricatives and affricates were produced with constriction and a groove configuration in the posterior region of the palate. Lateralised articulations were generally associated with complete contact across the palate, increased tongue-palate contact and, for some children, incomplete lateral seal was observed. Place of articulation (as revealed by EPG) varied for coronal targets heard as lateralised. Some children produced these sounds with contact in the alveolar region, others had palatal contact and one child had contact in the velar region. These differences in place of articulation had not been identified from an auditory-based analysis. One child was heard to produce dental fricatives and affricates, and the EPG patterns were found to have an asymmetrical groove configuration in the anterior region of the palate. The clinical implications of the findings are discussed.

Adolescent↗

A neurological model for childhood autism.

We analyze the behavioral and motor disturbances in childhood autism. On the basis of analogy to signs and conditions seen in adult neurology, we propose that the syndrome results from dysfunction in a system of bilateral neural structures that includes the ring of mesolimbic cortex located in the mesial frontal and temporal lobes, the neostriatum, and the anterior and medial nuclear groups of the thalamus. The mesolimbic cortex is cytoarchitectonically, angioarchitectonically, and neurochemically distinct and, along with the striatum, forms the entire target area of dopaminergic mesencephalic neurons. This raises the possibility that autism is related to neuromediator imbalance in those structures. Such dysfunction might be the result of macroscopic or microscopic changes in the target area or in structures functionally influencing them, consequent to a variety of causes such as perinatal viral infection, insult to the periventricular watershed area, or genetically determined neurochemical abnormalities.

Attention↗

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Brain Diseases↗

Callosal neglect.

BACKGROUND: According to the interhemispheric inhibition model of neglect, the uninjured hemisphere inhibits (via the corpus callosum) the injured hemisphere but the injured hemisphere can no longer inhibit the opposite hemisphere, which becomes hyperactive and produces an ipsilesional attentional bias. Alternatively, according to the compensation hypothesis, the uninjured hemisphere helps compensate for the damaged hemisphere, which is impaired in directing attention to contralateral stimuli. If the inhibition model of neglect is correct, callosal disconnection should reduce neglect. If the compensation model is correct, however, it may increase or induce neglect. PATIENT: A 32-year-old woman, at age 14 years, developed a right frontal astrocytoma and was treated with surgery and radiation but had a cardiopulmonary arrest secondary to aspiration. Subsequent imaging studies revealed damage to the frontal, parietal, and occipital regions of the right hemisphere and damage to the temporal region of the left hemisphere. After discharge, she was able to return to school and drive a car, without any evidence of neglect. About 10 years later, she developed complex partial and atonic seizures that were multifocal and medically intractable. She underwent a complete section of her corpus callosum at age 31 years. RESULTS: One year after the callosal section, she demonstrated (1) diminished spontaneous saccades to the left, hypometric leftward saccades, and left gaze impersistence; (2) left arm hemispatial limb akinesia; (3) unilateral spatial neglect; and (4) motor and cognitive impersistence. CONCLUSION: In patients with right hemisphere injury, callosal section may induce or enhance motor-intentional deficits and hemispatial neglect.

Adult↗

Short-wavelength sensitivity deficits in patients with migraine.

OBJECTIVE: To examine short-wavelength sensitivity in patients with migraine using short-wavelength automated perimetry (SWAP) and Stiles 2-color increment threshold procedures. METHODS: Twenty-five subjects with migraine with (n = 11) and without (n = 14) aura and 20 age-matched headache-free subjects underwent testing. All subjects underwent standard automated perimetry (SAP) and SWAP (using a Humphrey field analyzer; 24-2 presentation pattern). In 2 migraine patients (one with and another without aura), the 2-color increment threshold procedure was used to determine whether sensitivity losses were specific to short-wavelength sensitivity pathways or a generalized loss to multiple pathways. RESULTS: No statistically significant differences between migraine patients and controls were found for mean deviation (MD) or pattern-standard deviation (PSD) for SAP. However, for SWAP, MD and PSD were worse for the migraine group (P =.04). Twelve migraine patients had more than 4 locations with sensitivity worse than the 5% probability level (reference value). Increment threshold determinations in the 2 selected migraine patients indicated a selectively greater loss for short-wavelength sensitivity mechanisms. CONCLUSIONS: Approximately 50% of subjects with migraine (with or without aura) demonstrate SWAP sensitivity losses, at times between migraine events. These findings, in conjunction with previous results for SAP and flicker perimetry, suggest that migraine patients should be excluded from normative databases of visual function, and warrant further investigations of the relationship between migraine and glaucoma.

Adolescent↗

Visual phenomenology of the LSD flashback.

One hundred twenty-three persons with a history of LSD use were studied for the presence of the LSD flashback phenomenon and compared with 40 control subjects. A syndrome emerged that included ten distance visual disturbances. It had lasted for five years in half of the population, was treatable with benzodiazepines, exacerbated by phenothiazines, and precipitated by 19 different stimuli, most commonly emergence into a dark environment. Sensitivity to LSD as determined by flashbacks appears to divide the study sample into three discrete subgroups. There may be a genetic basis to LSD sensitivity.

Acute Disease↗

A comparison of the factor structure of the WISC and WISC-R in normal and exceptional groups.

Compared the factor structure of the WISC and WISC-R obtained in samples of children (N = 187) with various neuropsychological diagnoses with that obtained in Kaufman's study of the WISC-R standardization group. The relationships between WISC and WISC-R records scored in a manner consistent with the obtained factor structure, and the interdisciplinary diagnoses assigned children in both groups also were studied. It was found that the WISC and WISC-R factor structure obtained in both the samples including exceptional children was essentially comparable to that reported by Kaufman. Relationships between WISC and WISC-R factor scores and interdisciplinary diagnoses assigned children in both samples were weak, but generally consistent with expectations.

Attention Deficit Disorder with Hyperactivity↗