Childhood neglect is associated with reduced corpus callosum area.

BACKGROUND: Childhood abuse has been associated with abnormalities in brain development, particularly corpus callosum (CC) morphology. The impact of neglect has not been assessed, though it is the most prevalent form of childhood maltreatment. METHODS: Regional CC area was measured from magnetic resonance imaging scans in 26 boys and 25 girls admitted for psychiatric evaluation (28 with abuse or neglect) and compared with CC area in 115 healthy control subjects. Data were analyzed by multivariate analysis of covariance, with age and midsagittal area as covariates. RESULTS: Total CC area of the abused/neglected patients was 17% smaller than in control subjects (p =.0001) and 11% smaller than in psychiatric patients who had not been abused or neglected (contrast group; p =.01). Control subjects and the contrast group did not differ in total CC area. Neglect was the strongest experiential factor and was associated with a 15%-18% reduction in CC regions 3, 4, 5, and 7 (all p <.02). In contrast, sexual abuse seemed to be the strongest factor associated with reduced CC size in girls. CONCLUSIONS: These data are consistent with animal research that demonstrated reduced CC size in nursery-reared compared with semi-naturally reared primates. Early experience might also affect the development of the human CC.

Transient dopamine synthesis modulation in prefrontal cortex: in vitro studies.

The present study provides further evidence for transient D1 autoreceptor-like synthesis modulation in prefrontal cortex, but not striatum, of developing rats. DOPA accumulation was attenuated in a concentration-dependent manner in slices from the prefrontal cortex and striatum at 15 days of age by the partial D1 agonist SKF 38393 (0.01-10 microM) and the full D1 agonist SKF-81297 (0.01-10 microM) following NSD-1015; the response was no longer apparent by 40 days. Both agonists had greater potency in prefrontal cortex than striatum, and SKF-81297 exerted greater maximal inhibitory effects than SKF-38393. The inhibitory effects of both agonists were antagonized by pre-incubation with the D1 antagonist SCH-23390 in cortex, but not in striatum.

Differences in behavior and monoamine laterality following neonatal clomipramine treatment.

Postnatal treatment between 8 to 21 days of age with clomipramine (15 mg/kg, twice daily) produces an animal model that has many of the behavioral hallmarks of depression. In this study, we investigated the enduring behavioral and neurochemical effects of this early treatment in adult animals. Locomotor activity was increased in clomipramine-treated males, but not females, relative to vehicle-treated subjects. Increases in anxiety-like behavior in the elevated plus maze also were observed in clomipramine-exposed adults, but no sex differences were detected. Clomipramine-treated animals had shifts in the laterality of monoamines in limbic regions with lower serotonin levels on the right side while vehicle-treated animals had lower serotonin on the left side. The lateralization of dopamine content demonstrated the same pattern. This decline in monoaminergic content is consistent with clinical studies demonstrating decrements in serotonin as well as alterations in the lateralization of function in individuals with major depressive order.