Orbitofrontal Function and Educational Attainment
Orbitofrontal cortex (OFC) plays important roles in processes of reward and self-regulation. Lesions of OFC induce changes in personality and social conduct characterized by behavioral disinhibition, impulsivity, reduced autonomy, lack of concern with negative consequences, and mood lability. Many of these processes relate to aspects of education, so this study examined relationships between educational attainment and behavioral measures sensitive to OFC function (go/no-go, antisaccades, delayed alternation, and smell identification) in a sample of healthy adults. Results indicate that response inhibition errors relate inversely to educational attainment, while correct alternations and left nostril smell identification correlate positively. These relationships were independent of age and sex. These results are consistent the notion that OFC allows one to better pursue long-term goals with delayed rewards. Reciprocally, the process of education may also foster the development of such functions by reinforcing goal-directed behaviors and impulse control. ********** Prefrontal cortex (PFC) and associated subcortical structures play an important role in directing behavior, allowing it to be less dependent on immediate situational demands, and instead more autonomous and goal-directed (Cummings, 1995). Orbitofrontal cortex is a subdivision of prefrontal systems that play a role in various processes of reward and self-regulation. People with lesions of orbitofrontal cortex exhibit a profound change in personality and social conduct, characterized by behavioral disinhibition, jocularity, impulsivity, reduced autonomy, lack of concern with negative consequences, and mood lability (Malloy, Bihrle, & Duffy, 1993). Many exhibit impairments in judgement and decision making, exhibiting short-sighted and irresponsible behavior, with disastrous personal consequences (Eslinger & Damasio, 1985). Anosmia is another common consequence of orbitofrontal injury, due to localization of olfactory association cortex in OFC (Malloy et al., 1993). Orbitofrontal cortex is also critical for reward processes, and humans with orbitofrontal damage have impairments in the learning and reversal of reward associations (Rolls, 1994). The behavioral characteristics of OFC damage are arguably explainable by an underlying deficit in directing behavior based on reinforcement contingencies. Several tasks have been identified as sensitive to orbitofrontal function. Smell identification is one such measure, as evidenced by activation of OFC during olfactory identification tasks, and the presence of anosmia in individuals with orbitofrontal dysfunction (Savic, Bookheimer, Fried, & Engel, 1997; Savic, & Gulyas, 2000). As might be anticipated, emotional and personality characteristics are reflected in olfactory performance (Pause, Ferstl, & Fehm-Wolfsdorf 1998; Postolache, Doty, Wehr et al., 1999). Alternation tests are also sensitive to OFC function as demonstrated by animal and human lesion studies, as well as by functional neuroimaging studies in normal controls (Freedman, Black, Ebert, & Binns, 1998; Gold, Berman, & Randolph, 1996; Curtis, Zald, Lee, & Pardo, 2000; Zald, Curtis, Folley, & Pardo 2002). Motor inhibition measures (e.g. go/no-go tapping, antisaccades) are also sensitive to OFC function as indicated by lesion and electrophysiological studies in animals and humans (Drewe, 1975; Malloy, Rasmussen, Braden, & Haier, 1989; Ikeda, Luders, Collura, et al., 1996; Schoenbaum, Chiba, & Gallagher, 2000). These putative measures of OFC function intercorrelate, supporting the notion of common neural substrates (Spinella, 2002a). OFC dysfunction is associated with drug use, and these measures correlate with tobacco use (Spinella, 2002b). Motor inhibition (go/no-go tapping and antisaccades) and delayed alternation correlate with a subjective measure of impulsivity, the Barratt Impulsiveness Scale (Spinella, 2004) OFC functions would logically apply to several aspects of academic function. …