Abstract
It remains elusive how and why some people born with profound brain structure abnormalities develop high levels of intellect and near normal behaviour, while others with what appears to be the same or similar structural abnormalities experience far more concerning phenotypical outcomes. To begin to address this issue, a high-functioning female (aged 17 years at testing) born with complete callosal agenesis (ACC1) was tested on a series of psychophysical tests requiring unimanual-sequential or bimanual object weight discrimination; the latter of which is believed to depend on the integrity of the corpus callosum. In all five variants of the weight-discrimination task, ACC1’s performance was well within two standard deviations of the sample distribution mean. Arguably within the normal range, her performance warrants further investigation. Results suggest that individuals like ACC1 hold the secret to future understanding of the elusive neuro-compensatory processes of the human brain.