The influence of pubertal maturation on antisaccade performance.

Adolescence is a period characterized by continued improvements in inhibitory control, and this persisting immaturity is believed to interact with affective/motivational behavior to generate the impulsive and risk-taking behavior evidenced at this time. Puberty is a central event of adolescence that has been shown to influence affective/motivational behavior. However, despite plausible mechanisms by which puberty might influence inhibitory control, researchers have yet to test this possibility rigorously. Thus, we designed a study to examine the unique role of pubertal maturation, independent of age, in the development of inhibitory control. In order to minimize age-related variability while maximizing pubertal status variability, we recruited 78 participants (34 F) whose ages narrowly spanned the mean age of gonadarche for each sex (F: ages 11-13, M: ages 12-14). Two complementary measures were used to assess pubertal status: (1) circulating blood serum testosterone and estradiol levels reflecting internal manifestations of pubertal maturation, and (2) Tanner staging by a trained nurse reflecting pubertal maturation's external manifestations. Inhibitory control was assessed using the antisaccade task, and findings were adjusted for the potential effect of age. Results revealed no association between testosterone levels and error rates or response latencies in either sex. In girls, estradiol levels were not associated with error rates, but were associated with faster response latencies. There was similarly no association between Tanner status and error rates, although girls in more advanced pubertal stages showed faster response latencies. Power analyses indicate that findings of a lack of association did not reflect limited statistical power. Thus, in a study designed to isolate the effects of pubertal maturation independent of age, both external and internal indices of pubertal maturation converged to indicate that age-related improvements in cold antisaccade performance are independent of pubertal maturation.

Oculomotor assessments of executive function in preterm children.

OBJECTIVE: To use objective, nonverbal oculomotor tasks to assess executive function and infer the neural basis of impairments in preterm children. STUDY DESIGN: Cross-sectional study of preterm children age 9-16 years (n = 69; mean gestational age 29 weeks) and full-term controls (n = 43). Tasks assessed sensorimotor function (reflexive prosaccades); resistance to peripheral distracters (fixation); response inhibition, response preparation, and execution of a voluntary saccade (antisaccades); and spatial working memory (memory-guided saccades). Group differences were analyzed using ANOVA. We used linear regression to analyze the contributions of age, sex, gestational age, and white matter category to task performance. RESULTS: Preterm children did not differ from controls on basic sensorimotor function, response inhibition, and working memory. Compared with controls, preterm children showed greater susceptibility to peripheral distracters (P = .008) and were slower to initiate an inhibitory response (P = .003). Regression models showed contributions of age and white matter category to task performance. CONCLUSIONS: Preterm children show intact basic sensorimotor function and demonstrate difficulties in processes underlying executive control, including increased distractibility and prolonged response preparation. These limitations may reflect specific neural abnormalities in fronto-subcortical executive control of behavior.