Typically, these connections are unable to drive neuronal activity25 (ie, independently generate spiking outputs) but have the ability to modulate information processing by enhancing (or decreasing) neural responses.26 Patterns of amygdala connectivity without closely examining the different components of the amygdala complex have been discussed. Yet, the connectivity pattern of the central

nucleus is quite distinct from the one observed for regions such as the Inhibitors,research,lifescience,medical anterior basolateral and lateral nuclei of the amygdala. The latter have been suggested to be part of a frontotemporal association system, in contrast to the central nucleus, which is more directly linked to autonomic structures.27 More generally, when discussing the functions of the amygdala, it is thus important to consider how distinct subregions of this structure are anatomically connected. Prefrontal monitoring and control Inhibitors,research,lifescience,medical of visceral and other bodily functions The idea that the prefrontal cortex is involved in the control of the autonomic nervous system is not new, dating to the turn of the 20th century (see the historical account by Neafsey28). Inhibitors,research,lifescience,medical More recently, the tight interrelation between prefrontal cortex and bodily

functions was refined by the work of Damasio, Bechara, and colleagues on the somatic marker hypothesis (ie, the idea that bodily Inhibitors,research,lifescience,medical PF-01367338 price states function as “marker” signals that influence reasoning and decision making), especially with respect to the orbitofrontal and ventromedial prefrontal cortices.29 Likewise, the notion that the anterior insula – a region that is here discussed in conjunction with prefrontal sites – is involved in complex bodily representations, has gained visibility30-32 Cingulate cortex The functions of the cingulate cortex, which may comprise more than 30 to 40 subareas, are complex.33 The anterior sector of the cingulate gyrus is involved in a broad array of functions,

including Inhibitors,research,lifescience,medical willed action, executive functions, and emotion. A remarkable property of this cortical tissue is that it probably has a more extensive descending projection system than any other cortical region,34 including major projections to autonomic regulatory structures, notably the lateral hypothalamus, periaqueductal gray, parabrachial nucleus, and the nucleus of the solitary tract.35 This connectivity Phosphatidylinositol diacylglycerol-lyase is consistent with stimulation studies that have documented effects of cingulate electrical stimulation on virtually all autonomic and many endocrine functions.33 Conversely, a range of brain stem projections influence cingulate responses.36 These include projections from the locus coeruleus to sites throughout the cingulate cortex, as well as from the nucleus of the solitary tract. Several nociceptive circuits also reach anterior- and mid-cingulate areas indirectly via thalamic nuclei.