Saccadic system functioning among schizophrenia patients and their first-degree biological relatives.

In Study 1, 30 schizophrenia Ss and 27 nonpsychiatric comparison Ss were presented with a fixation task, a visually guided reflexive saccade (prosaccade) task, a predictive tracking task (0.4-Hz square wave), and an antisaccade task. The 2 groups did not differ on either the fixation or prosaccade tasks. Schizophrenia Ss had an increased number of errors on the antisaccade task and had decreased rightward visually guided saccade amplitudes during the predictive tracking task. In Study 2, 13 psychiatric comparison Ss and 32 1st-degree biological relatives of the schizophrenia Ss were compared with the schizophrenia Ss and a larger and older sample of nonpsychiatric Ss (n?=?33) on the predictive tracking and antisaccade tasks. The groups did not differ on predictive saccadic tracking. The schizophrenia Ss and their 1st-degree biological relatives made more errors on the antisaccade task than both the nonpsychiatric and psychiatric comparison groups (who did not significantly differ). Results are consistent with the notion that dysfunction of dorsolateral prefrontal cortex, caudate nucleus, or both is related to liability for schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Resting EEG in first-episode and chronic schizophrenia

Prostatic acid phosphatase, prostate-specific antigen, and zinc as markers of prostate, and fructose as marker of seminal vesicles were investigated in the seminal plasma of 35 idiopathic asthenozoospermic and 20 normal subjects to evaluate their relationship with sperm motility. Total seminal plasma levels of the three prostatic markers and, to a lesser extent, total fructose levels were lower in asthenozoospermic patients, and in all the pooled subjects, the same levels were directly correlated with the motility of ejaculated spermatozoa. When the levels of the biochemical markers were expressed as concentrations in seminal plasma, only prostatic acid phosphatase levels remained lower in asthenozoospermic patients and they maintained a direct correlation with sperm motility in all the pooled subjects. The PAP/Zn/Fr (representing the ratio between PAP concentration and free Zn available for spermatozoan uptake) was lower in asthenozoospermic patients and it was also directly related to sperm motility in all the pooled subjects. These data suggest that altered sperm motility is associated with a probable impairment of sex accessory gland function in subjects with idiopathic asthenozoospermia, while prostatic acid phosphatase seems mainly related to sperm motility.     

Eye tracking dysfunction in schizophrenia: Characterization of component eye movement abnormalities, diagnostic specificity, and the role of attention.

To characterize oculomotor components and diagnostic specificity of eye tracking abnormalities in schizophrenia, we examined a large consecutively admitted series of psychotic patients and matched controls. The most common abnormality in schizophrenic patients was low gain (slow) pursuit eye movements (47% of cases). Pursuit and saccadic eye movement abnormalities were no more severe in schizophrenic Ss than in those with affective psychoses, except that high rates of catch-up saccades were unique to schizophrenic Ss (17% of cases). These findings indicate that impaired pursuit eye movements are a major cause of eye tracking impairments in schizophrenia, that tracking dysfunctions commonly occur in affective psychoses, and that markedly high rates of catch-up saccades during eye tracking may be specific to schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Smooth pursuit in schizophrenia: abnormalities of open- and closed-loop responses

This study, funded by the National Breast Screening Programme, was undertaken in 1992 at the Helen Garrod Breast Screening Unit, Nottingham. In a sample of 400 women who attended first round screening in 1989 and remained eligible for screening 10 per cent failed to attend triennial recall. A sample of a further 400 women who had been screened previously containing 200 women who re-attended for second round screening and 200 who failed to re-attend were studied anonymously by questionnaire. No significant difference existed between re-attenders and non-re-attenders in their perceived personal risk of breast cancer. A significant difference existed between the two groups in (1) their knowledge of breast cancer, (2) their ease of attending for screening, and (3) their previous experience of breast screening. Half of the women who failed to return implicated their initial visit in this decision--41 per cent implicating pain, 6 per cent stress and 3 per cent embarrassment. Hence a small percentage (5 per cent) of women do not re-attend for screening because of a negative experience at their initial visit. Every effort should therefore be made to make screening as acceptable as possible.     

Smooth-pursuit eye movement dysfunction and liability for schizophrenia: Implications for genetic modeling.

41 nonpsychiatric Ss, 38 probands with schizophrenia, and 99 of their relatives were studied. Oculomotor functioning was bimodally distributed for probands and relatives. Oculomotor dysfunction was not present in all families with a schizophrenic proband. In those families in which it was present, there were significant phenotypic correlations between oculomotor functioning and schizophrenia-related characteristics. The patterns of familial resemblance in the families in whom oculomotor dysfunction was present were consistent with nonadditive genetic variance contributing both to oculomotor dysfunction and to the relationship between oculomotor dysfunction and clinical symptoms. These results suggest that schizophrenia may be etiologically heterogeneous and that oculomotor dysfunction may help to identify nonadditive genetic variance for this disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of joint maintenance and production strategies in a subcontracting environment

This article, inspired by an industrial problem, develops efficient maintenance and just-in-time production policies in a subcontracting environment according to two orientations. The first invokes subcontracting with the objective of satisfying a constant customer demand knowing that our production system, composed of a machine M ₁, cannot satisfy the totality of demand. Subcontracting is represented by a machine M ₂ which has a constant failure rate, while three maintenance policies for M ₁ are tested and evaluated. The second orientation takes the perspective of our production system as a supplier which is obliged to allocate part of its production capacity to subcontracting so as to satisfy a constant demand. We consider a production system made up of two machines, both of which produce a single type of product, are subject to breakdowns and can carry out subcontracting tasks. The objective of this part of the article is to prove the efficiency of the so-called integrated maintenance policy, which combines production and maintenance decisions in a subcontracting environment.     

Handedness in first-episode psychotic patients and their first-degree biological relatives.

We evaluated the handedness of 58 schizophrenia patients and 54 of their relatives, 23 patients with major depression with psychosis and 24 of their relatives, 36 patients with bipolar psychosis and 33 of their relatives, and 119 nonpsychiatric Ss and 42 of their relatives. Computerized tomography measures were also available for a subset of the psychotic patients. The schizophrenia patients were significantly more left-handed than any of the other groups, and increased sinistrality was also associated with larger lateral ventricle to brain area ratios. The relatives of the schizophrenia patients did not significantly differ on handedness from either the relatives of the affective psychosis patients or the nonpsychiatric Ss. Findings do not support the notion that left-handedness in schizophrenia is genetically influenced. More research with larger family member data sets is warranted to further explore this possibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychometric detection of schizotypy: Perceptual aberration and physical anhedonia in relatives of schizophrenics.

Administered scales of Perceptual Aberration (PERAB) and Physical Anhedonia (PHYSAN), traits that may be related to risk for schizophrenia, to 54 schizophrenics, 146 of their 1st-degree relatives (evaluated for schizophrenia-related disorders), and 178 normal Ss (screened for psychotic disorders in them or their relatives). For both scales, there was a significant effect of group membership. For the PERAB scale, the schizophrenics had higher scores than the normal Ss, who had higher scores than the relatives. For the PHYSAN scale, schizophrenics had higher scores than their relatives, who had higher scores than the normal Ss. Patterns of familial correlations also suggested that physical anhedonia, but not perceptual aberration, may be familial among schizophrenics and their relatives. The PHYSAN scale, but not the PERAB one, may be a useful indicator of liability for schizophrenia among the relatives of affected probands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Familial prevalence and coaggregation of schizotypy indicators: A multitrait family study.

Schizophrenic probands (n?=?17), their 1st-degree relatives (n?=?61), and medically and psychiatrically screened normal control Ss (n?=?18) were studied with structured interviews for Diagnostic and Statistical Manual of Mental Disorders (DSM-III) Axis I disorders and schizotypal personality disorder, questionnaire measures of schizotypy, measures of smooth-pursuit eye movement dysfunction, and attention dysfunction. Schizophrenic Ss scored abnormally on essentially all measures. Relatives differed significantly from control Ss on most measures. Correlational analyses indicate that many characteristics tested in these measures run together in families. The data are consistent with the hypothesis that a single vulnerability dimension or typology, presumably in part genetically transmitted, may account for phenotypically distinct abnormalities. These traits, taken together, may have joint usefulness for identifying persons with a predisposition to schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)