Ailsa Russell

Neuropsychological functioning in adults with Asperger syndrome

There is some consensus in the literature regarding the cognitive profile of people with Asperger syndrome (AS). Findings to date suggest that a proportion of people with AS have higher verbal than performance IQ, a non-verbal learning disability (NVLD) and impairments in some aspects of executive function (EF). However, there are few published studies on adults with AS and many have compared the AS group to an autistic control group alone. We compared cognitive functioning in 27 AS adults without a history of language delay and 20 normal controls who did not differ significantly in age, gender and IQ. People with AS had significant impairments on a test of visual memory and on EF tasks measuring flexibility and generativity, but not inhibition. There was no significant difference between verbal and performance IQ. Our results suggest that impairments on tests requiring flexibility of thought and generation occur at all ages and across a range of autistic disorders including AS.

Prefrontal and medial temporal correlates of repetitive violence to self and others

BACKGROUND The neurobiological basis for violence in humans is poorly understood, yet violent behavior (to self or others) is associated with large social and healthcare costs in some groups of patients (e.g., the mentally retarded). The prefrontal cortex and amygdalo-hippocampal complex (AHC) are implicated in the control aggression, therefore we examined the neural integrity of these regions in violent patients with mild mental retardation and nonviolent control subjects. METHODS We used (1)H-magnetic resonance spectroscopy (MRS) to measure 1) concentrations and ratios of N-acetyl aspartate (NAA), creatine phosphocreatine (Cr+PCr), and choline-related compounds (Cho) in prefrontal lobe of 10 violent inpatients and 8 control subjects; 2) ratios of NAA, Cr+PCr, and Cho in the AHC of 13 inpatients and 14 control subjects; and 3) frequency and severity of violence in patients. RESULTS Compared to control subjects, violent patients had significantly (p <.05, analysis of covariance-age and IQ as confounding covariates) lower prefrontal concentrations of NAA and Cr+PCr, and a lower ratio of NAA/Cr+PCr in the AHC. Within the violent patient group, frequency of observed violence to others correlated significantly with prefrontal lobe NAA concentration (r = -0.72, p <.05). CONCLUSIONS NAA concentration indicates neuronal density, and Cr+PCr concentration high-energy phosphate metabolism. Our findings suggest that violent patients with mild mental retardation have reduced neuronal density, and abnormal phosphate metabolism in prefrontal lobe and AHC compared to nonviolent control subjects. Further studies are needed, however, to determine if these findings are regionally specific, or generalize to other groups of violent individuals.

Executive functioning differences between adults with attention deficit hyperactivity disorder and autistic spectrum disorder in initiation, planning and strategy formation

Executive functioning deficits characterize the neuropsychological profiles of the childhood neurodevelopmental disorders of attention deficit hyperactivity disorder (ADHD) and autistic spectrum disorder (ASD). This study sought to determine whether similar impairments exist in adults with ADHD (N = 53) and ASD (N = 45) in comparison with a healthy control group (N = 31), whether the two disorders can be distinguished on the basis of their executive functioning features, and whether these impairments are related to symptom severity. Both clinical groups were found to exhibit executive functioning deficits. The ADHD group had difficulty withholding a response, with relative preservation of initiation and planning abilities. In contrast, the ASD group exhibited significant impairments in initiation, planning and strategy formation. The specific executive functioning deficits were related to severity of response inhibition impairments in ADHD and stereotyped, repetitive behaviours in ASD. These findings suggest the pattern of executive functioning deficits follows a consistent trajectory into adulthood.

Cognitive behavior therapy for comorbid obsessive-compulsive disorder in high-functioning autism spectrum disorders: a randomized controlled trial.

High rates of anxiety disorders, particularly obsessive compulsive disorder (OCD) are reported in people with Autism spectrum disorders (ASD). Group cognitive behavioral treatment (CBT) has been found effective for anxiety in young people with ASD but not been OCD specific. One uncontrolled pilot study of individual CBT for OCD for adults with ASD showed good treatment efficacy.

Which characteristics of schizophrenia predate psychosis

Neuropsychological and brain structural abnormalities are present in first onset schizophrenia; the balance of evidence is that in the majority of cases these are developmental in origin. A proportion of first degree relatives also show lateral ventricular enlargement, cortical volume decrease and possibly loss of the normal cerebral asymmetry; these findings suggest that certain families transmit a genetic defect in the control of neurodevelopment. On the contrary, decrement in left hippocampal volume appears to be secondary to perinatal hypoxia. High risk, follow-back and cohort studies all demonstrate that preschizophrenics as a group show deviant development; delayed milestones, lower IQ, solitary play, excessive anxiety, and minor neurological problems are all common. It seems likely, but not proven, that these are a manifestation of underlying neurodevelopmental disorder.

Premorbid IQ in patients with functional psychosis and their first-degree relatives

Numerous studies have found deficits in premorbid IQ in schizophrenic patients, but it is not clear whether this deficit is shared by (a) patients with other functional psychoses, and (b) relatives of these patients. Ninety-one schizophrenic patients, 66 affective psychotic patients (29 schizoaffective and 37 manic or depressed), and 50 normal control subjects were administered the National Adult Reading Test (NART) which provides an estimate of premorbid IQ. The NART was also completed by 85 first-degree relatives of schizophrenic patients and by 65 first-degree relatives of affective psychotic patients. After adjustments were made for sex, social class, ethnicity and years of education, schizophrenic patients had significantly lower premorbid IQ than their relatives, the affective psychotic patients and controls. Manic and depressed patients had significantly lower NART scores than their first-degree relatives, but schizoaffective patients did not, and neither group differed significantly from controls. There was no significant difference in premorbid IQ between patients who had experienced obstetric complications (OC+) and those who had not (OC-). Both OC+ and OC- schizophrenic patients differed significantly from their relatives, but the disparity was greatest between OC+ patients and their relatives. Relatives of OC+ schizophrenic patients had significantly higher IQ than relatives of OC- schizophrenic patients.

The influence of life events on the subsequent course of psychotic illness: A prospective follow-up of the Camberwell Collaborative Psychosis Study

Fifty-nine psychotic patients with acute onset of illness, who had been interviewed about their experience of stressful life events before the episode, were followed up for an average of 42 months. Thirty patients (51%) had experienced a stressful life event in the 3 months immediately before onset (EV+), 29 had not (EV-). In patients with an RDC diagnosis of affective disorder or unspecified functional psychosis, the presence of stressful life events was associated subsequently with milder symptom severity, less time spent in hospital, more treatment for depressive symptoms and less for psychotic symptoms. In schizophrenia, differences were less apparent, but patients with event associated episodes had less need of anti-psychotic maintenance medication over the follow-up period and tended to have spent more time in complete remission. EV+ schizophrenic subjects also had higher morbid risk for schizophrenia in their first degree relatives, and tended to be female and to have less typical symptoms than EV- schizophrenic patients.

High functioning autism spectrum disorders: an investigation of psychological vulnerabilities during interrogative interview

Forensic psychologists and psychiatrists are commonly asked to ascertain the reliability of statements made by suspects to the police during questioning and to assess an individuals vulnerability to providing information which is inaccurate, unreliable, and misleading during police interview. Autism spectrum disorders (ASD) are characterised by qualitative impairments in social communication and interaction, and a restricted or repetitive pattern of behaviours, interests, and activities. It is not clear whether people with ASD are more vulnerable at interview, or more prone to respond negatively to interrogative pressure, when compared with the general population. In the present study, 26 individuals with high functioning ASD, and 27 gender- and IQ-matched controls, were compared on measures of interrogative suggestibility and compliance as well as on measures of anxiety, depression, the extent to which they feared negative evaluation by others, and whether they had a suspicious outlook. There were no significant between-group differences on the measures of suggestibility, but the group with ASD were rated as significantly more compliant than the controls in terms of both parental and self-report, and also had higher scores on measures of depression, anxiety, fear of negative social evaluation and paranoia. Bi-modal distribution of suggestibility scores within the ASD group indicates that individual characteristics should be taken into account when considering an assessment. Individuals with ASD may be more eager to please or to avoid conflict and confrontation than controls, and may be more prone to respond compliantly to requests and demands.

IQ in childhood psychiatric attendees predicts outcome of later schizophrenia at 21 year follow-up.

Objective: Preschizophrenic children who merit psychiatric referral are claimed to have a particularly malevolent illness when the psychosis develops later. The 21 years outcome of a sample of such children was investigated.

The mental health of individuals referred for assessment of autism spectrum disorder in adulthood: A clinic report

Growing awareness of autism spectrum disorders has increased the demand for diagnostic services in adulthood. High rates of mental health problems have been reported in young people and adults with autism spectrum disorder. However, sampling and methodological issues mean prevalence estimates and conclusions about specificity in psychiatric co-morbidity in autism spectrum disorder remain unclear. A retrospective case review of 859 adults referred for assessment of autism spectrum disorder compares International Classification of Diseases, Tenth Revision diagnoses in those that met criteria for autism spectrum disorder (n = 474) with those that did not (n = 385). Rates of psychiatric diagnosis (>57%) were equivalent across both groups and exceeded general population rates for a number of conditions. The prevalence of anxiety disorders, particularly obsessive compulsive disorder, was significantly higher in adults with autism spectrum disorder than adults without autism spectrum disorder. Limitations of this observational clinic study, which may impact generalisability of the findings, include the lack of standardised structured psychiatric diagnostic assessments by assessors blind to autism spectrum disorder diagnosis and inter-rater reliability. The implications of this study highlight the need for careful consideration of mental health needs in all adults referred for autism spectrum disorder diagnosis.