ABSTRACT
This investigation assessed the hypothesis that conduct disordered juveniles may suffer from a maturational lag in the development of behaviors believed associated with the frontal cortex. Twenty conduct disorder (CD) juveniles and 20 normal comparison subjects were compared on nine Lurian tasks that measure behavior attributed to frontal lobe functioning. A three-way ANOVA, with gender, race, and group as factors of interest, revealed significant differences on the verbal conflict task, verbal retroactive inhibition task, and on a measure of receptive vocabulary. Using receptive vocabulary as a covariate, an ANCOVA showed no significant differences between the groups on any of the tasks. These findings appear to support the potential impact that language dysfunction can have in the development of disinhibitory behavior. Other interpretations of the findings are presented.
ABSTRACT
Heilman and Valenstein (Clinical Neuropsychology, 1979, Oxford University Press, New York) have hypothesized a right hemispheric mechanism which mediates attention bilaterally. Shapiro and Hynd ("The development of functional lateralization in visual hemifield attention." Developmental Neuropsychology, Vol. 1, pp 67-80, 1985) examined the developmental validity of this model and their findings did not provide evidence for a lateralized mechanism for visual hemifield attention in 9, 13, and 18 year olds. However, length of foreperiod and gender effects were noted. This study attempted to compare these groups with a group of normal adults (ages 25-35) using the same reaction time paradigm. The study demonstrated support for the length of foreperiod effect found by Shapiro and Hynd. Hand effects were also found. However, these results do not lend support to either the model proposed by Heilman and Valenstein (1979) or Shapiro and Hynd's (1985) notion of developmental differences across age groups with respect to right hemisphere dominance for mediating attention.
