Beliefs profoundly affect people's lives, but their cognitive and neural pathways are poorly understood. Although previous research has identified the ventromedial prefrontal cortex (vmPFC) as critical to representing religious beliefs, the means by which vmPFC enables religious belief is uncertain. We hypothesized that the vmPFC represents diverse religious beliefs and that a vmPFC lesion would be associated with religious fundamentalism, or the narrowing ofreligious beliefs. To test this prediction, we assessed religious adherence with a widely-used religious fundamentalism scale in a large sample of 119 patients with penetrating traumatic brain injury (pTBI). If the vmPFC is crucial to modulating diverse personal religious beliefs, we predicted that pTBI patients with lesions to the vmPFC would exhibit greater fundamentalism, and that this would be modulated by cognitive flexibility and trait openness. Instead, we found that participants with dorsolateral prefrontal cortex (dlPFC) lesions have fundamentalist beliefs similar to patients with vmPFC lesions and that the effect of a dlPFC lesion on fundamentalism was significantly mediated by decreased cognitive flexibility and openness. These findings indicate that cognitive flexibility and openness are necessary for flexible and adaptive religious commitment, and that such diversity of religious thought is dependent on dlPFC functionality.

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Objective: We investigated the association between regional white and gray matter volume loss and performance on executive functions (EFs) in patients with penetrating traumatic brain injury (pTBI). Methods:We studied 164 pTBI patients and 43 healthy controls from the Vietnam Head Injury Study. We acquired CT scans for pTBI patients and divided them according to lesion localization (left and right prefrontal cortex [PFC]). We administered EF tests (Verbal Fluency, Trail Making, Twenty Questions) and used voxel-based lesion symptom mapping (VLSM) and group-based correlational and multiple regression analyses to examine the relative influence of gray and white matter lesions on EF recovery. Results:The VLSM analysis revealed that white and gray white matter lesions were associated with impaired EFs. In the left PFC lesion group, damage to the PFC gray matter, anterior corona radiata, and superior longitudinal fasciculus (SLF) were most correlated with functional recovery. Verbal Fluency, which involves a broad fronto-temporo-parietal network, was best predicted by SLF lesion volume. Trail Making and Twenty Questions, which is associated with more focal left frontal damage, was better predicted by PFC lesions. Conclusions:Our results indicated that white matter volume loss can be a superior predictor of recovery and a crucial factor driving clinical outcome in functions involving a broad network such as Verbal Fluency. White matter damage may place additional burden on recovery by deteriorating signal transmission between cortical areas within a functional network. Neurology ® 2015;84:1394-1401 GLOSSARY ACR 5 anterior corona radiata; ANOVA 5 analysis of variance; D-KEFS 5 Delis-Kaplan Executive Function System; EF 5 executive function; HC 5 healthy control; IFG 5 inferior frontal gyrus; IPG 5 inferior parietal gyrus; LACR 5 left anterior corona radiata; LPFC 5 left prefrontal cortex lesions; LSLF 5 left superior longitudinal fasciculus; MFG 5 middle frontal gyrus; PFC 5 prefrontal cortex; pTBI 5 penetrating traumatic brain injury; RPFC 5 right prefrontal cortex lesions; SCR 5 superior corona radiata; SFG 5 superior frontal gyrus; SLF 5 superior longitudinal fasciculus; SPG 5 superior parietal gyrus; TBI 5 traumatic brain injury; VLSM 5 voxel-based lesion system mapping. Traumatic brain injury (TBI) is a major public health problem worldwide.1 While physical deficits following TBI generally improve over time, cognitive impairments can persist 2,3 and cause permanent disability. 1,4 Some of the most persistent deficits after TBI involve executive functions (EFs), resulting in impaired mental flexibility and planning. 5,6 Extensive functional neuroimaging and lesionmapping evidence indicates that the prefrontal cortex (PFC) plays a central role in EFs. [6][7][8] EFs also involve interactions between frontal and posterior brain regions. 9,10 To date, the majority of lesion-mapping studies have focused on the cortical gray matter correlates of functional impairment, yet white matter involvement has rarely been q...