Peter A. Fried
Carleton University
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Neurotoxicology and Teratology | 2003
Peter A. Fried; Barbara Watkinson; Robert Gray
Cognitive performance was examined in 145 thirteen- to sixteen-year-old adolescents for whom prenatal exposure to marihuana and cigarettes had been ascertained. The subjects were from a low-risk, predominantly middle-class sample participating in an ongoing, longitudinal study. The assessment battery included tests of general intelligence, achievement, memory, and aspects of executive functioning (EF). Consistent with results obtained at earlier ages, the strongest relationship between prenatal maternal cigarette smoking and cognitive variables was seen with overall intelligence and aspects of auditory functioning whereas prenatal exposure to marihuana was negatively associated with tasks that required visual memory, analysis, and integration. The interpretation of the results is discussed in terms of the differential observations related to in utero exposure to cigarettes and marihuana and the nature of the cognitive variables associated with the two drugs.
Journal of Developmental and Behavioral Pediatrics | 1990
Peter A. Fried; Barbara Watkinson
Aspects of neurobehavioral development were examined in 133 36-month- and 130 48-month-old children for whom prenatal exposure to marijuana, cigarettes, and alcohol had been previously ascertained and who have been assessed since birth. Parallelling earlier observations made with this sample at 12 and 24 months, prenatal exposure to cigarette smoking was significantly associated with poorer language development and lower cognitive scores at both 36 and 48 months after statistically controlling for confounding factors. Relatively low levels of maternal alcohol consumption, which had measurable effects at 24 and 36 months, no longer had significant relationships with outcome variables at 48 months of age. At 48 months, significantly lower scores in verbal and memory domains were associated with maternal marijuana use after adjusting for confounding variables. This negative relationship is the first reported association beyond the neonatal stage, and may represent a long-term effect of the drug upon complex behavior that, at a younger age, had not developed and/or could not be assessed.
Neurotoxicology and Teratology | 2001
Peter A. Fried; Andra M. Smith
In spite of marihuana being the most widely used illegal drug among women of reproductive age, there is a relative paucity of literature dealing with the neurobehavioral consequences in offspring--particularly the longer-term effects. However, there is a degree of consistency in the limited data, both across cross-sectional reports and longitudinally, where offspring have been followed for a number of years. Two cohort studies fall into the latter category; one involving a low-risk sample and, the other, a high-risk sample. Global IQ is not impacted by prenatal marihuana exposure but aspects of executive function (EF)--in particular, attentional behavior and visual analysis/hypothesis testing--appear to be negatively associated with in utero cannabis exposure in children beyond the toddler stage. This hypothesized influence of prenatal marihuana on EF is examined and discussed relative to effects (or lack of effects) across different ages in the offspring, cannabinoid receptors, and the extant general marihuana and prefrontal literature.
Journal of Developmental and Behavioral Pediatrics | 1992
Peter A. Fried; O'Connell Cm; Watkinson B
Cognitive and receptive language development were examined in 135 60-month-old and 137 72-month-old children for whom prenatal exposure to marijuana, cigarettes, and alcohol had been ascertained. Discriminant Function analysis revealed an association between prenatal cigarette exposure and lower cognitive and receptive language scores at 60 and 72 months. This paralleled and extended observations made with this sample at annual assessments at 12 to 48 months of age. Unlike observations made at 48 months, prenatal exposure to marijuana was not associated with the cognitive and verbal outcomes. Relatively low levels of maternal alcohol consumption did not have significant relationships with the outcome variables. The importance of assessing subtle components rather than global cognitive and language skills to detect potential behavioral teratogenic effects of the drugs being examined is discussed.
Neurotoxicology and Teratology | 1988
Peter A. Fried; Barbara Watkinson
The motor, mental, and language development plus the home environment was examined in 217 twelve-month and 153 twenty-four-month-old children for whom prenatal exposure to marijuana, alcohol and cigarettes was previously ascertained. With this low-risk sample multiple regression analysis was used to assess the association between outcome measures and prenatal drug exposure while adjusting for potential confounding factors. Prenatal exposure to marijuana was uniquely positively associated with a series of items evaluating the childs attitudes and interests that reflect a cognitive factor. Moderate levels of alcohol were significantly associated with lower mental scores at 24 months of age. Prenatal maternal cigarette smoking was significantly associated with lower mental scores at 12 months of age and altered responses on auditory items at 12 and 24 months. However, at 24 months, the strong relationship of postnatal environmental factors with cognitive outcomes and with prenatal maternal smoking resulted in loss of significant, unique predictive power for maternal smoking. Based on the present work and supplemented by previously reported data pertaining to maternal attitudes during pregnancy and neonatal behaviour, a transactional interpretation is presented.
Neurotoxicology and Teratology | 1987
Peter A. Fried; C.M. O'Connell
Maternal use of cigarettes, alcohol, cannabis, and caffeine was established for four time periods; prepregnancy, first trimester, third trimester and average use over pregnancy. The relationship between such usage and growth parameters of offspring followed up from birth to 12 and 24 months of age were examined. Of the soft drugs used, nicotine had the most pronounced effect. After adjustment for other relevant variables, nicotine use prior to and during pregnancy was negatively related to weight and head circumference at birth. Furthermore, third trimester nicotine use was a stronger predictor of decreased weight and head circumference at birth than was first trimester use. The results obtained are consistent with ponderal index (PI) literature suggesting a recovery of growth retardation in infants with a lowered PI. Average consumption of greater than one ounce of absolute alcohol per day was negatively related to birth weight and length. Neither cannabis nor caffeine use had a significant negative effect on any growth parameter.
Neurotoxicology and Teratology | 1987
Peter A. Fried; J.E. Makin
Infant neonatal behaviour is significantly and differentially related to maternal marihuana, cigarette and alcohol use during pregnancy. Data on 250 babies born to healthy, predominantly middle-class women were analyzed using canonical analysis and multiple regression adjusting for potentially confounding variables. Prenatal marihuana exposure was associated with increased tremors and startles and poorer habituation to visual stimuli, prenatal cigarette exposure with increased tremors and poorer auditory habituation, whereas a relatively low level of alcohol consumption was marginally related to increased neonatal irritability.
Neurotoxicology and Teratology | 1991
Judy Makin; Peter A. Fried; Barbara Watkinson
Previous research has determined that maternal smoking during pregnancy is associated with negative effects for the child at birth and throughout childhood. Much less is known about the consequences of exposure to secondary smoke during fetal development. The present study investigates and compares the long-term consequences of active and passive smoking during pregnancy. Ninety-one children between the ages of six and nine years were tested using a comprehensive neuropsychological test battery. After considering potential confounds, children of nonsmoking mothers generally were found to perform better than the two smoking groups on tests of speech and language skills, intelligence, visual/spatial abilities and on the mothers rating of behavior. The performance of children of passive smokers was found, in most areas, to be between that of the active smoking and nonsmoking groups. It was concluded that there is a continuum of long-term smoking effects and that, although active maternal smoking is associated with effects of greater breadth and magnitude than passive maternal smoking, children of passive smokers are also at risk for a pattern of negative developmental outcomes.
Neurotoxicology and Teratology | 1997
Peter A. Fried; Barbara Watkinson; Linda S. Siegel
Facets of reading and language were examined in 131 9- to 12-year-old children for whom prenatal exposure to marijuana and cigarettes had been ascertained. The subjects were from a low-risk, predominantly middle class sample who are participants in an ongoing longitudinal study. Discriminant Function Analysis revealed a dose-dependent association that remained after controlling for potential confounds, between prenatal cigarette exposure and lower language and lower reading scores, particularly on auditory-related aspects of this latter measure. The findings are interpreted as consistent with earlier observations of an association between cigarette smoking during pregnancy and altered auditory functioning in the offspring. Similarities and differences between the reading observations and dyslexia are discussed. Maternal prenatal passive smoke exposure did not appear to contribute to either the language or reading outcomes at this age but postnatal secondhand smoke exposure by the child was associated with poorer language scores. Prenatal marijuana exposure was not significantly related to either the reading or language outcomes.
Journal of Developmental and Behavioral Pediatrics | 1987
Peter A. Fried; Barbara Watkinson; Richard F. Dillon; Corinne S. Dulberg
The neurological status of 9− and 30-day-old infants, as assessed by the Prechtl neurological examination, was significantly and differentially related to prenatal exposure of cigarettes, marijuana, and alcohol. Data on approximately 250 babies, born to healthy, white, predominantly middle-class women, were analyzed using discriminant function analyses controlling for potentially confounding variables. Prenatal cigarette exposure was associated with hypertonicity and increased nervous system excitation, particularly at 30 days, prenatal marijuana exposure was associated with symptoms similar to mild narcotic withdrawal, and prenatal exposure to relatively low levels of alcohol was associated with slightly lowered nervous system arousal at 9 days of age. The results were related to behavioral observations on neonates exposed to drugs prenatally. J Dev Behav Pediatr 8:318–326, 1987. Index terms: cigarettes, marijuana, alcohol, neonatal neurological status, withdrawal.