” 64 Table I Summary of neuroanatomical progressions within paleocortical and archicortical trends and their putative functional characteristics. Key elements from each of these suggestions should probably be accounted for in a mature model of frontal lobe function. In prior work it was suggested that integrating the evolutionary cytoarchitectonic trends model with the Pribram and McGuinness theory of attentlonal
control might have merit.70,71,77-83 Specifically, it has been argued that the dorsal and medial archicortical systems Inhibitors,research,lifescience,medical may emphasize the stabilization of behavioral programs, thus subserving what Pribram and McGuinness referred to as “tonic activation” – and this would be consistent particularly with roles in mediating “projectional control,” “willed intentions,” “monitoring of information in working memory,” and “expectation” as invoked above. In contrast, it was suggested that the ventral and lateral paleocortical system is biased towards flexibility and is engaged in mediation and moderation of “phasic Inhibitors,research,lifescience,medical arousal”—and this would be compatible with the ideas espoused above regarding
“responsive control,” “stimulus intentions,” and elements of “retrieval and encoding” particularly those that demand or are triggered by perceptual “classification” processes. This functional distinction Inhibitors,research,lifescience,medical is also likely linked to both Inhibitors,research,lifescience,medical neurochemical distinctions and differences in cellular signaling pathways that are under strong genetic regulation. For example, this distinction between maintaining the stability (through tonic dopaminergic activation) or introducing more flexibility (through phasic dopaminergic arousal) in corticostriatal networks was seen as a key mechanism through which genetic variation in the catechol-O-methyltransferase (COMT) gene may impact diverse cognitive functions.83 The putative identification of these features and characteristics with paleocortical Inhibitors,research,lifescience,medical and archicortical trends is summarized in Table I. Future directions
Modern neuroimaging studies, particularly those usinctional magnetic resonance imaging (fMRI), have already produced an enormous amount of evidence that remains to be well integrated with our understanding of connectional anatomy and with functional anatomic hypotheses that are constrained by structural anatomic architecture. Oxymatrine It is hoped that data emerging from the human connectome project will help advance application of these anatomic constraints to functional models.84 Surging interest in the “default mode network”85 may also help by increasing understanding of functional network Adriamycin clinical trial activation free of the constraints of specific cognitive hypotheses that may lead to reification of certain functional networks because these are dictated by the experiments.