Biomedical subjects

Peter H Venables

Publications and source records attributed to Peter H Venables.

6 recordsLinked to original sources

PubMed2005

Reduced electrodermal activity in psychopathy-prone adolescents.

This study tests the hypothesis that psychopathy-prone adolescents show reduced anticipatory skin conductance responding. Electrodermal activity was recorded while participants anticipated and responded to a 105 dB signaled or unsignaled white-noise burst. Using an extreme groups design, the authors used Child Psychopathy Scale (D. R. Lynam, 1997) scores from a community sample of 335 male adolescents (age 16) to form control (n = 65) and psychopathy-prone (n = 65) groups. Significantly more psychopathy-prone participants were nonresponders in the signaled anticipatory (p = .014), signaled responsivity (p = .037), and unsignaled responsivity (p = .003) conditions compared with controls. Anticipatory hyporesponsivity of psychopathy-prone adolescents similar to the electrodermal hyporesponsivity found in psychopathic adults suggests that this autonomic impairment is present by adolescence and may predispose individuals to adult psychopathy.

Acoustic Stimulation↗

PubMed2004

Malnutrition at age 3 years and externalizing behavior problems at ages 8, 11, and 17 years.

OBJECTIVE: Poor nutrition is thought to predispose to externalizing behavior problems, but to date there appear to have been no prospective longitudinal studies testing this hypothesis. This study assessed whether 1) poor nutrition at age 3 years predisposes to antisocial behavior at ages 8, 11, and 17 years, 2) such relationships are independent of psychosocial adversity, and 3) IQ mediates the relationship between nutrition and externalizing behavior problems. METHOD: The participants were drawn from a birth cohort (N=1,795) in whom signs of malnutrition were assessed at age 3 years, cognitive measures were assessed at ages 3 and 11 years, and antisocial, aggressive, and hyperactive behavior was assessed at ages 8, 11, and 17 years. RESULTS: In relation to comparison subjects (N=1,206), the children with malnutrition signs at age 3 years (N=353) were more aggressive or hyperactive at age 8 years, had more externalizing problems at age 11, and had greater conduct disorder and excessive motor activity at age 17. The results were independent of psychosocial adversity and were not moderated by gender. There was a dose-response relationship between degree of malnutrition and degree of externalizing behavior at ages 8 and 17. Low IQ mediated the link between malnutrition and externalizing behavior at ages 8 and 11. CONCLUSIONS: These results indicate that malnutrition predisposes to neurocognitive deficits, which in turn predispose to persistent externalizing behavior problems throughout childhood and adolescence. The findings suggest that reducing early malnutrition may help reduce later antisocial and aggressive behavior.

Adolescent↗

PubMed2003

Malnutrition at age 3 years and lower cognitive ability at age 11 years: independence from psychosocial adversity.

BACKGROUND: Early malnutrition is linked to poor cognition, but long-term effects have not been extensively examined and psychosocial confounds have not always been controlled. OBJECTIVE: To test the hypothesis that malnutrition at age 3 years will be associated with poorer cognitive ability at age 11 years independent of psychosocial confounds. DESIGN: A prospective, longitudinal study of a birth cohort of 1559 children originally assessed at age 3 years for malnutrition (low hemoglobin level, angular stomatitis, kwashiorkor, and sparse, thin hair) and followed up to age 11 years. SETTING AND PARTICIPANTS: A community sample of 1559 children (51.4% boys and 48.6% girls) born between September 1, 1969, and August 31, 1970, in 2 towns in the island of Mauritius, with 68.7% Indians and 25.7% Creoles (African origin). MAIN OUTCOME MEASURES: Verbal and spatial ability measured at ages 3 and 11 years and reading, scholastic ability, and neuropsychologic performance measured at age 11 years. RESULTS: Malnourished children had poorer cognition at both ages. Deficits were stable across time, applied to all sex and ethnic groups, and remained after controlling for multiple measures of psychosocial adversity. Children with 3 indicators of malnutrition had a 15.3-point deficit in IQ at age 11 years. CONCLUSIONS: Malnutrition at age 3 years is associated with poor cognition at age 11 years independent of psychosocial adversity. Promoting early childhood nutrition could enhance long-term cognitive development and school performance, especially in children with multiple nutritional deficits.

Anemia↗

PubMed2002

Increased psychophysiological arousal and orienting at ages 3 and 11 years in persistently schizotypal adults.

Abnormalities of psychophysiological arousal and orienting are thought to predispose to schizophrenia, but there have been no prior studies of early psychophysiological functioning in "persistent schizotypals" who remain stably schizotypal across time. This study assessed skin conductance (SC) arousal and orienting at ages 3 and 11 years, electroencephalography (EEG) at age 11 years, and behavior problems at age 17 years in 52 individuals who were stably schizotypal from ages 17 to 23 years, and 104 normal controls. Schizotypy was assessed at age 17 with the Schizophrenism scale, and at age 23 with the Schizotypal Personality Questionnaire (SPQ). Schizotypals had significantly increased SC arousal and increased SC amplitudes to neutral and aversive stimuli at both ages 3 and 11, and also reduced slow-wave left hemisphere EEG power at the beginning of the Continuous Performance Task (CPT) at age 11. Group differences in SC were greater for aversive than neutral stimuli. Schizotypals also had higher age 17 behavior ratings on psychotic behavior, anxiety-withdrawal, and conduct disorder. Findings indicate that heightened SC arousal and orienting in early childhood is a significant risk factor for later schizotypal personality, support a left hemisphere overactivation hypothesis of schizotypy, and illustrate the potential value of a longitudinal definition of persistent schizotypy.

Adolescent↗

PubMed2002

Spatial but not verbal cognitive deficits at age 3 years in persistently antisocial individuals.

Previous studies have repeatedly shown verbal intelligence deficits in adolescent antisocial individuals, but it is not known whether these deficits are in place prior to kindergarten or, alternatively, whether they are acquired throughout childhood. This study assesses whether cognitive deficits occur as early as age 3 years and whether they are specific to persistently antisocial individuals. Verbal and spatial abilities were assessed at ages 3 and 11 years in 330 male and female children, while antisocial behavior was assessed at ages 8 and 17 years. Persistently antisocial individuals (N = 47) had spatial deficits in the absence of verbal deficits at age 3 years compared to comparisons (N = 133), and also spatial and verbal deficits at age 11 years. Age 3 spatial deficits were independent of social adversity, early hyperactivity, poor test motivation, poor test comprehension, and social discomfort during testing, and they were found in females as well as males. Findings suggest that early spatial deficits contribute to persistent antisocial behavior whereas verbal deficits are developmentally acquired. An early-starter model is proposed whereby early spatial impairments interfere with early bonding and attachment, reflect disrupted right hemisphere affect regulation and expression, and predispose to later persistent antisocial behavior.

Adolescent↗

PubMed2002

Stimulation seeking and intelligence: a prospective longitudinal study.

The prediction that high stimulation seeking 3-year-olds would have higher IQs by 11 years old was tested in 1,795 children on whom behavioral measures of stimulation seeking were taken at 3 years, together with cognitive ability at 11 years. High 3-year-old stimulation seekers scored 12 points higher on total IQ at age 11 compared with low stimulation seekers and also had superior scholastic and reading ability. Results replicated across independent samples and were found for all gender and ethnic groups. Effect sizes for the relationship between age 3 stimulation seeking and age 11 IQ ranged from 0.52 to 0.87. Findings appear to be the first to show a prospective link between stimulation seeking and intelligence. It is hypothesized that young stimulation seekers create for themselves an enriched environment that stimulates cognitive development.

Achievement↗