Non-Right-Handedness and Obstetrical Complications in Paranoid Hallucinatory Schizophrenics

Abstract

In previous studies a link between pregnancy complications, minor physical anomalies and non-right-handedness was described in schizophrenic patients. There is evidence of an anomaly in the lateralization process in schizophrenia. Many studies of handedness and schizophrenia have found that schizophrenic patients have an increased rate of non-right-handedness compared with normal subjects. The contemporary neurodevelopmental hypothesis of schizophrenia emerged from pathobiological findings. In addition there is evidence for early brain lesions and malformations in fetal brain development. Especially pregnancy and birth complications have been found to be a risk factor for the later development of schizophrenia. In this study we set out to test the possible association between diagnosis and handedness, diagnosis and risk factors, as well as gender and handedness for 60 patients (30 men, 30 women) and 60 controls. The percentage of non-right-handedness was significantly elevated in the patient group (p = 0.0025). In a gender-specific analysis this result could be confirmed only for male patients. Peri- and postnatal developmental risk factors were significantly elevated in schizophrenics compared with controls. The percentage of all risk factors in the male group of schizophrenic non-right-handers was significantly elevated compared with right-handed male schizophrenics.

Handedness in schizophrenia and schizoaffective disorder in an afrikaner founder population

“…This finding is in contrast with those of some studies that have found no gender differences in relation to handedness in schizophrenia whereas several authors have found an association between non-right handedness and the male gender [11][12][13][14][15] . Our study found no association between age at onset of illness and handedness in schizophrenia/ schizoaffective disorder.…”

“…The relationship between gender, atypical handedness and schizophrenia has also been studied but the results are inconsistent. Some studies have found no gender differences in relation to handedness in schizophrenia whereas several authors have found an association between non-right handedness and the male gender [10][11][12][13][14][15] . In contrast, a study by Kenneth et al showed that patients with schizophrenia and their mentally well relatives had an excess of mixed handedness compared to controls, and this excess was specific to female patients suffering from schizophrenia.…”

Handedness in schizophrenia: a quantitative review of evidence

“…left–mixed–right, as in Table 2), being entirely based on assessment of multiple manual activities using either self‐report or demonstration. Six studies (20, 25–29) used the ‘right’ vs. ‘non‐right’ classification (i.e. combining both left‐ and mixed‐handers together), and six studies (11, 12, 15, 19, 30, 31) used the ‘mixed’ vs. ‘non‐mixed’ classification (i.e.…”

Endophenotypes in schizophrenia: A selective review

“…While the scoring of handedness varied in strictness between articles, each article presented frequencies for abnormal (all versions of non-right) handedness, which allowed for the comparison of percent abnormal between diagnostic groups between studies. A total of 16 articles fulfilled our selection criteria, with some articles reporting data for multiple handedness categories (3 non-right: O’Callaghan et al, 1995; Sperling et al, 1999; Yan et al, 1985; and 11 left: Clementz, Iacono et al, 1994; Dragovic and Hammond, 2005; Egan, Hyde et al, 2001; Green, Satz, Smith et al, 1989; Lawrie et al, 1999a; Malesu et al, 1996; Nelson et al, 1993; Reilly et al, 2001; Shapleske et al, 2001; Taylor and Abrams, 1984; Upadhyay et al, 2004; and 10 mixed: Dragovic and Hammond, 2005; Egan, Hyde et al, 2001; Giotakos, 2001; Green, Satz, Smith et al, 1989; Gureje, 1988; Malesu et al, 1996; Nelson et al, 1993; Reilly et al, 2001; Taylor and Abrams, 1984; Upadhyay et al, 2004). Percent abnormal calculations are presented in Table 3.…”