Amygdala pathology in Parkinson's disease

Abstract

The amygdala undergoes severe pathological changes during the course of Parkinson's disease (PD). Lewy bodies and Lewy neurites are distributed in a specific manner throughout the nuclear complex. The lesional pattern displays only minor interindividual variation. The most prominent changes occur in the accessory cortical and central nuclei. The cortical, accessory basal and granular nuclei show less severe alterations, while the basal and lateral nuclei, as well as the intercalated cell masses, generally remain uninvolved. The amygdala receives a broad range of afferents, allowing integration of exteroceptive information with interoceptive data. It generates major projections to the isocortex (the prefrontal cortex in particular), limbic system (hippocampus and entorhinal region) and centers regulating endocrine and autonomic functions. The specific lesional pattern seen in PD destroys part of the nuclear gray matter and its connections and, thus, may likely contribute to the development of behavioral changes and autonomic dysfunctions.

Longitudinal evaluation of cerebral morphological changes in Parkinson's disease with and without dementia

“…This is consistent with post-mortem data showing neuronal loss and Lewy body pathology in insular cortex and cingulate gyrus in PD [5,7]. Moreover, hypoperfusion of insular region in a group of non-demented advanced PD has been re- * Each reported anatomical location exceeds a voxelwise statistical threshold of p < 0.001 uncorrected level.…”

Early diagnosis of Parkinson's disease

“…SPECT examinations in these relatives show a reduced DAT tracer uptake in some of the subjects (4 out of 25 relatives), indicating a premotor alteration of the dopaminergic system [74]. These results are in line with the neuropathological findings of Braak et al revealing that the emergence of Lewy bodies at the olfactory system and related areas may pre-date Lewy body formation at the substantia nigra [74][75][76].…”

Stages in the development of Parkinson’s disease-related pathology

“…The central subnucleus sends a major descending and poorly myelinated fiber tract both to the nuclei of the gain setting system and the dorsal motor nucleus of the vagal nerve; in so doing, it exerts a superordinate "limbic" influence on both of these modulatory lower brain stem regions and regulates them ( Fig. 4; Amaral et al 1987;Sims and Williams 1990;Braak et al 1994;Bohus et al 1996). Additional brain regions that become involved in stage 3 include the cholinergic tegmental pedunculopontine nucleus (GarciaRill 1991; Inglis and Winn 1995;Rye 1997;Pahapill and Lozano 2000), the oral raphe nuclei, the cholinergic magnocellular nuclei of the basal forebrain (Candy et al 1983;Whitehouse et al 1983;Mesulam et al 1992), and the hypothalamic tuberomamillary nucleus (Del .…”