Oculomotor delayed response abnormalities in young offspring and siblings at risk for schizophrenia

Individuals with schizophrenia are know to demonstrate cognitive and behavioral difficulties, particularly alterations in executive functions, including working memory. It is unclear whether these deficits reflect trait-related vulnerability to schizophrenia indicators and can be assessed by studying nonpsychotic relatives of patients with schizophrenia. In this study, we used an oculomotor delayed response (ODR) paradigm to examine spatial working memory in 37 "high-risk" child and adolescent offspring and siblings (age range=6-25 years) of patients with schizophrenia or schizoaffective disorder. Compared with 37 age- and sex-matched healthy controls (age range=6-23 years), high-risk subjects showed nonsignificantly greater errors in the ODR task at longer delay intervals. Statistical analyses suggested that performance improved with age in healthy control subjects, whereas it worsened with age in high-risk subjects. In both groups, the ODR errors were generally associated with poorer sustained attention (Continuous Performance Test: visuospatial d prime), somewhat poorer executive function (Wisconsin Card Sorting Test), and elevated Heinrichs-Buchanan neurological soft signs scores. These findings indicate the presence of spatial working memory abnormalities in individuals at risk for schizophrenia. Furthermore, these abnormalities may be progressive in nature. The ODR task is a valuable indicator of prefrontal cortical function and spatial working memory and may be a potentially valuable marker for familial risk of schizophrenia.     

Anhedonia and perceptual aberration in first-episode psychotic patients and their relatives

One hundred eighteen psychiatric patients, each experiencing his or her first lifetime episode of psychosis, 125 of their first-degree relatives, and 155 normal subjects were assessed using the physical anhedonia, social anhedonia, and perceptual aberration scales of Chapman et al. (1976, 1978). We hypothesized that psychotic subjects would obtain higher scores on these scales than their relatives and the controls, and we expected the group of relatives to score more deviantly than the normal controls. The physical anhedonia and social anhedonia scales successfully differentiated the psychiatric patients from the relatives and the latter from the normal subjects. These findings testify to the construct validity of the scales and suggest that they tap a predisposition to psychosis. Unexpectedly, the relatives scored lower on the perceptual aberration scale than did the normal controls, perhaps because the relatives adopted a defensive response set.     

Smooth-pursuit eye tracking in first-episode psychotic patients and their relatives.

We wished to determine the specificity of smooth-pursuit eye tracking dysfunction to schizophrenia and the prevalences of dysfunction among functionally psychotic and normal individuals. Therefore, we investigated pursuit tracking in a large sample of psychotic patients, normal subjects, and first-degree relatives (N = 482). Patients were recruited as part of an epidemiological study of first-episode psychosis that used a broadly based referral network to identify all cases in a major metropolitan area over a 2 1/2-year period. Patients received diagnoses of schizophrenia, schizophreniform disorder, psychotic mood disorder, and paranoid or other psychotic disorder based on the third edition of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1980). The distribution of tracking performance was bimodal for the schizophrenic patients and their relatives, perhaps reflecting major gene action. Moreover, poor tracking ran in families. Pursuit tracking dysfunction was relatively specific to schizophrenic patients and their relatives and occurred infrequently in other psychotic patients and normal subjects.     

Schizotypy in relatives of patients with schizophrenia

Previous studies indicate that relatives of patients with schizophrenia are more likely to present characteristics of schizotypal personality than the general population. Few transcultural studies of schizotypy have been carried out. Most instruments constructed to measure schizotypy have been applied in specific cultures; conceivably, in other populations its components may be distributed in different ways. These cultural differences may affect the relations between schizotypy and schizophrenia. The objective of this study is to obtain data on schizotypy in relatives of patients with schizophrenia and relatives of patients with other disorders in a Latin American rural population. The results suggest that cultural factors must be taken into account in order to establish the relationship between schizotypy and schizophrenia.     

Clinical and pathol-anatomic findings in corpus callosum deficiency, enlarged cavum septi pellucidi, and septal defect]

A comparison is made of the pathological changes of the median line structures such as corpus deficiency, enlarged cavum septi pellucidi (Csp.) and septal defects in 10,457 pneumo-encephalography (PEG) examinations of neurological and psychiatric patients, and in 11,016 general autopsy cases. Clinical peculiarities in corpus deficiency and other development anomalies of the median line structures are discussed along with case reports. A predominance of the male sex in cases of enlarged Csp. together with frequent combinations with neurological and psychiatric illness were noticeable, particularly oligophrenia, behavioral disorders, epilepsy and cerebral tumours. Thus, certain inferiority of the dysrhaphic mutation of the central organ can be assumed.     

Quality of life assessment in Turkish patients with schizophrenia and their relatives

Quality of life of first-degree relatives living in the same household with patients having schizophrenia has not been sufficiently explored. 30 patients with schizophrenia (16 women, 14 men), diagnosed using DSM-IV criteria, 31 of their relatives (15 women, 16 men), and 34 control subjects (21 women, 13 men) were included in the study. The mean age of the patients, their relatives, and the control subects were 39.8 +/- 10.9, 58.1 +/- 12.5 and 37.3 +/- 17.0, respectively. The World Health Oranization Quality of Life-Brief Form was administered to all subjects. Quality of life was worse for the patient group than for their relatives and control subjects, but relatives of the patients and control subjects were not significantly different on Quality of life. Quality of life was negatively correlated with the severity of psychopathology and extrapyramidal side effects induced by antipsychotic drugs in the patients.     

Interval-timing deficits in individuals at high risk for schizophrenia

A duration-bisection procedure was used to study the effects of signal modality and divided attention on duration classification in participants at high genetic risk for schizophrenia (HrSz), major affective disorder (HrAff), and normal controls (NC). Participants learned short and long target durations during training and classified probe durations during test. All groups classified visual signals as shorter than equivalent duration auditory signals. However, the difference between auditory and visual signal classification was significantly larger for the HrSz group than for the NC group. We posit a model in which there is a clock rate difference between auditory and visual signals due to an attentional effect at the level of a mode switch that gates pulses into an accumulator. This attentionally mediated clock rate difference was larger for the HrSz participants than for the NC participants, resulting in a larger auditory/visual difference for the HrSz group.     

Attribution and expressed emotion in the relatives of patients with schizophrenia.

Indexes of expressed emotion (EE) in 58 relatives of patients with schizophrenia were related to those relatives' spontaneously expressed causal beliefs about the illness and about related symptoms and behaviors. Relatives made attributions predominantly to factors external, universal, and uncontrollable from their own perspective, and to factors internal, universal, and uncontrollable from the patient's perspective. Low-EE relatives were similar in their attributions to emotionally overinvolved relatives. Compared with these two groups, critical and/or hostile relatives made more attributions to factors personal to and controllable by the patient. Subsequent analyses suggested that hostile relatives were further characterized by making more attributions to factors internal to the patient and by making attributions with fewer causal elements.     

Clinical correlates of anhedonia and perceptual aberration in first-episode patients with schizophrenia and affective disorder.

We examined the association between scales measuring physical anhedonia, social anhedonia, and perceptual aberration and premorbid functioning, clinical state, and current level of adjustment in 91 psychotic subjects. The patients were examined at the onset of their first psychotic episode and again 18 months later. For patients with schizophrenia, anhedonia was significantly related to premorbid functioning. No association was found between the scales and clinical state or level of adjustment at intake or follow-up. In affective disorder patients, no correlation was found between premorbid functioning (a stable characteristic) and scale scores, but moderately large correlations emerged between the scales and clinical state and level of adjustment at both assessment times. These results suggest that schizophrenic and affective disorder patients endorse items on these scales for different reasons. We hypothesize that for patients with schizophrenia, the scales assess enduring personality characteristics, whereas for the affective disorder patients, they assess clinical condition at the time of testing.     

Motor impairment and antisocial behavior in adolescent males at high risk for schizophrenia

A familial link between schizophrenia and antisocial behavior has been established (e.g., Silverton, 1985). This study examined this relationship in a Danish cohort. The subjects were 36 high-risk males (offspring of a schizzophrenic parent) and 36 low-risk males (offspring of parents without psychopathology). This high-risk subjects exhibited more antisocial behavior than the low-risk subjects. We tested the hypothesis of a correlation between neurointegrative deficits, as defined by motor impairment, and antisocial behavior, rated at ages 10–13, in subjects at genetic risk for schizophrenia. Path analyses were conducted from motor impairment at 1 year and motor impairment at 10–13 years to antisocial behavior separately for high-risk and low-risk subjects. Adolescent motor impairment was a significant predictor of antisocial behavior for high-risk subjects. Motor impairment at 1 year was also associated with antisocial behavior for these subjects, although the association was partly due to the indirect effects of motor impairment at 1 year on motor impairment at 10–13 years, which, in turn, was associated with changes in antisocial behavior. As predicted, none of the path coefficients nor the effect coefficient was significant for low-risk subjects.     

Somatosensory processing and schizophrenia liability: proprioception, exteroceptive sensitivity, and graphesthesia performance in the biological relatives of schizophrenia patients

In the present study, the authors examined somatosensory processing in 30 biological relatives of persons with schizophrenia (hereafter called "schizophrenia relatives"), 30 biological relatives of persons with bipolar affective disorder (psychiatric family control subjects), and 30 healthy control subjects with no family history of psychopathology. All 3 groups completed a weight discrimination task, a 2-point discrimination task, and a complex cognitive somatosensory task (i.e., graphesthesia). The schizophrenia relatives performed significantly worse on all 3 somatosensory tasks compared with both the healthy control subjects and the bipolar relatives. The healthy control subjects and psychiatric family control subjects showed no significant differences on any of the somatosensory tasks. Within the weight discrimination and 2-point discrimination tasks, schizophrenia relatives showed group differences on the d' index, the measure of sensitivity, whereas all 3 groups did not differ on lnbeta, the measure of response bias, suggesting a genuine difference in weight and touch sensitivity. The d' value of the weight discrimination task was significantly associated with both the cognitive-perceptual factor and negative symptom factor of the clinical questionnaire (e.g., Schizotypal Personality Questionnaire; SPQ), whereas the 2-point discrimination d' value and graphesthesia scores were significantly associated only with the cognitive-perceptual factor of the SPQ. Implications for the possible relation between somatosensory task performance and schizophrenia liability are discussed.     

Two adolescents at risk for schizophrenia: A family case study

This is a study of the complex factors that contributed to the development of adolescent psychoses in two stepbrothers, ages 12 and 15. The identified patient, the younger boy, was in what appeared to be a reversible stage of early adolescent psychosis and his 15 year old newly acquired stepbrother in a nonreversible stage. Each boy was a mentally gifted, neurologically handicapped adolescent who was inextricably vulnerable on the basis of his neurodevelopmental sensitivity to specific immobilizing parental fears and conflicts. Their inherent problems set them apart from their intact teenage sisters and affected the nature and quality of their total life experience. Those working with psychotic children and their families must bear these relationships in mind for optimal strategic intervention and change. In the management of psychotic adolescents and their families, the individual and family therapist could work to everyone's disadvantage if these important neurodevelopmental difficulties are not considered.1979, SummerThis study was supported in part by the Maternal and Child Health Services Training and Study Project No. 144, Department of Health, Education and Welfare.     

Two adolescents at risk for schizophrenia: A family case study

This is a study of the complex factors that contributed to the development of adolescent psychoses in two stepbrothers, ages 12 and 15. The identified patient, the younger boy, was in what appeared to be a reversible stage of early adolescent psychosis and his 15 year old newly acquired stepbrother in a nonreversible stage. Each boy was a mentally gifted, neurologically handicapped adolescent who was inextricably vulnerable on the basis of his neurodevelopmental sensitivity to specific immobilizing parental fears and conflicts. Their inherent problems set them apart from their intact teenage sisters and affected the nature and quality of their total life experience. Those working with psychotic children and their families must bear these relationships in mind for optimal strategic intervention and change. In the management of psychotic adolescents and their families, the individual and family therapist could work to everyone's disadvantage if these important neurodevelopmental difficulties are not considered.This study was supported in part by the Maternal and Child Health Services Training and Study Project No. 144, Department of Health, Education and Welfare.     

Nonreligious coping and religious coping as predictors of expressed emotion in relatives of patients with schizophrenia

Expressed emotion (EE) is a measure of the amount of criticism and emotional over involvement expressed by a key relative towards a relative with a disorder or illness. Research has established that living in a high EE environment, which is characterised by increased levels of critical and emotionally exaggerated communication, leads to a poorer prognosis for patients with a mental illness when compared to low EE environments. Despite evidence that EE is a strong predictor of the course of the illness, there continue to be questions concerning why some family members express excessive levels of high EE attitudes about their mentally ill relatives while others do not. Based on indirect evidence from previous research, the current study tested whether religious and nonreligious coping serve as predictors of EE. A sample of 72 family members of patients with schizophrenia completed an EE interview, along with questionnaires assessing situational nonreligious coping and religious coping. In line with the hypotheses, results indicated that nonreligious coping predicted EE. Specifically, less use of adaptive emotion-focused coping predicted high EE. Also consistent with predictions, maladaptive religious coping predicted high EE above and beyond nonreligious coping.     

A taxometric analysis of cognitive and neuromotor variables in children at risk for schizophrenia

A taxometric model was applied to detect a subgroup or taxon of children conjectured to be at highest risk for developing schizophrenia or related disorders in a sample of offspring of schizophrenic, depressed, and normal parents. Measures of cognitive and neuromotor performance in childhood were used as indicator tests in the analyses. A taxon consisting chiefly of children of schizophrenic parents was detected. Forty-seven percent of those children were assigned to the taxon, compared with 16% of the children of depressed parents and 4% of the children of normal parents. Assignment to the taxon is assessed in relation to the current functional status of the subjects in young adulthood.     

RT distributional analysis of cognitive-control-related brain activity in first-episode schizophrenia

Impairments in cognitive control are a defining feature of schizophrenia. Aspects of cognitive control include proactive control—the maintenance of task rules or goals to bias attention and maintain preparedness—and reactive control—the engagement of attention in reaction to changing cognitive demands. Proactive control is thought to be particularly impaired in schizophrenia. We sought to examine proactive and reactive control in schizophrenia, as measured by reaction time (RT) variability, and especially long RTs, which are thought to represent lapses in proactive control, during the Stroop paradigm. Furthermore, we sought to examine the neural underpinnings of lapses in proactive control and the subsequent engagement of reactive control in those with schizophrenia, as compared to healthy controls, using fMRI. We found that patients with schizophrenia displayed greater RT variability and more extremely long RTs than controls suggesting that proactive control was weaker in the schizophrenia than in the control group. All of the subjects engaged regions of the cognitive control network during long RTs, consistent with an engagement of reactive control following a failure in proactive control on these trials. The schizophrenia group, however, displayed significantly diminished activity in these regions relative to controls. Our results suggest increased failures in proactive control, but also impaired reactive control, in schizophrenia as compared to healthy subjects.     

Glucose metabolism,hippocampal subfields and cognition in first-episode and never-treated schizophrenia

BackgroundPrevious studies have indicated that glucose metabolism and altered hippocampal structure and function play a pivotal role in cognitive deficits in schizophrenia (SZ). This study was designed to explore the inter-relationship between glucose metabolism, hippocampal subfield volume, and cognitive function in the antipsychotics-naive first episode (ANFE) SZ patients.MethodsWe chose the fasting insulin, glucose, and insulin resistance (HOMA-IR) index as biomarkers of glucose metabolism. Cognitive function was assessed by the MATRICS Consensus Cognitive Battery (MCCB). The hippocampal subfield volume, glucose metabolism biomarkers, and cognitive function were evaluated in 43 ANFE SZ and 29 healthy controls (HCs).ResultsCompared with HCs, SZ patients had higher fasting blood glucose and insulin levels and HOMA-IR (all p < 0.05). Correlation analysis revealed that category fluency performance was positively associated with fasting glucose level. Fasting insulin or HOMA-IR was positively associated with the hippocampal subfield volume in patients (all p<0.05). Moreover, the spatial span index score was associated with the volume of the right presubiculum, subiculum, and right hippocampal tail. In addition, multiple regression analysis found that the interaction effects of insulin × right fimbria or insulin × left fimbria were independent predictors of the MCCB total score.ConclusionsOur findings suggest that abnormal glucose metabolism and cognitive decline occur in the early stage of SZ. The interaction between abnormal glucose metabolism and hippocampal subfields was associated with cognitive functions in SZ.     

The role of recollection in source memory: an examination of schizophrenia patients and their first-degree relatives

Source recognition memory deficits have repeatedly been observed in people with schizophrenia (SZ), and have also recently been observed in their first-degree relatives. These deficits have been hypothesized to result, at least in part, from impairments in the conscious recollection process. Although other processes are clearly also affected in SZ, it has been proposed that impairments in the conscious recollection process could be a parsimonious explanation for the source memory deficits observed in their relatives. Here, we tested 25 patients with SZ and 34 of their non-affected parents, as well as two groups of matched healthy controls, on a short-term associative memory task that shares the characteristics of standard source recognition tasks but minimizes the need for recollection of stored information from memory. This task was administered in order to determine if deficits can still be observed in these people when involvement of the conscious recollection process is minimized. We observed deficits on our short-term source memory task in people with SZ, but their first-degree relatives did not share this deficit. These results support the idea that multiple memory processes supporting associative/source memory are affected in SZ, whereas the source memory deficits previously observed in relatives of SZ seem specific to tasks that rely on the conscious recollection process.