While the interhemispheric connectivity for the ACC and the DLPFC was significantly lower among patients than controls, the correlation between degree of connectivity in these regions and outcome only trended toward significance with outcome. Though the associations between interheispheric functional connectivity and outcome observed in the current study do not fully support the hypothesis that frontal lobe functional brain synchronicity is associated with executive functions post-TBI, the results are not entirely surprising, as resting state interhemispheric connectivity should not be assumed to have a strong association with functional or neurocognitive outcome in this clinical population. Patients with TBI, even TAI present with very heterogeneous injury profiles including mechanism of injury, injury severity, and most importantly location of brain lesions. Although every patient in this sample was selected based on having a head injury consistent with traumatic axonal injury, the degree of injury to particular white matter structures undoubtedly varied widely. For example, Benson et al. (2007)10 examined the integrity of whole-brain white matter of twenty patients with TAI using a histogram analysis and demonstrated that the distribution of white matter
