Advances in Cytoarchitectonic Mapping of the Human Amygdala and the Hippocampus
Olga Kedo1*, Karl Zilles1,2,3 and Katrin Amunts1,2,4
1Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, Germany
2JARA-BRAIN, Jülich-Aachen Research Alliance, Germany
3Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Germany
4C. and O. Vogt-Institute for Brain Research, Heinrich-Heine-University Düsseldorf, Germany
*Corresponding author: Olga Kedo, Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, 52425 Jülich, Germany, E-mail: firstname.lastname@example.org
Clin Med Img Lib, CMIL-2-034, (Volume 2, Issue 3); ISSN: 2474-3682
Published Date: March 23, 2016
Citation: Kedo O, Zilles K, Amunts K (2016) Advances in Cytoarchitectonic Mapping of the Human Amygdala and the Hippocampus. Clin Med Img Lib 2:034.
Copyright: © 2016 Kedo O, et al. This is an open-access content distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Amygdala, Hippocampus, Cytoarchitecture
The human amygdala and hippocampus are key structures for emotion and memory processing. They are involved in various neurological and psychiatric disorders. Since each of both brain regions is structurally and functionally extremely segregated , their numerous subdivisions are implicated to different degrees in specific pathological processes, e.g. epilepsy [2,3].
Although modern functional imaging techniques can assign dysfunctions to the whole amygdala or hippocampus after specific impairments , the disorder- or lesion-specific involvement of the clearly defineable, and functionally as well as structurally diverse cytoarchitectonic subdivisions remains to be elucidated. Therefore, cytoarchitectonic probability maps are a prerequisite for an anatomically sufficiently precise localization of functional imaging data . This was realized by registration of probability maps of the subdivisions of the amygdala and hippocampus to a stereotaxic reference space, which is also used for the localization of functional imaging data. E.g., a prevailing contribution of the basolateral amygdala was revealed by using this combined approach in impaired acquisition of conditioned fear in patients with Urbach-Wiethe disease .
Here we present further advanced cytoarchitectonic parcellations of the amygdala (Figure 1) and the hippocampal formation (Figure 2). The cytoarchitectonic identification of the subdivisions of the hippocampus and amygdala in histological sections is the basis of the fine-grained probability maps, as well as of volumetric measurements.
Figure 1: Cytoarchitecture of the amygdala and neighboring cortical and subcortical structures in a coronal section of a human postmortem brain. The centromedial nucleus is labelled by an orange line and the basolateral complex by a red line. The VCo belongs to the superficially located part of the amygdala. AAA anterior amygdaloid area, APir amygdalopiriform transition area, BL basolateral nucleus, BM basomedial nucleus, BV basoventral nucleus, Ce central nucleus, f fiber bundles, i intercalated islands, La lateral nucleus, Me medial nucleus, PL paralaminar nucleus, VCo (ventral) cortical nucleus. Neighbouring structures: Cl Claustrum, Ent entorhinal cortex, F endorhinal sulcus, Hi hippocampus, NbM Nucleus basalis of Meynert, TrO Tractus opticus, V lateral ventricle.
Source: Figure 1 (minimally altered) "Springer Anat Embryol, Cytoarchitectonic mapping of the human amygdala, hippocampal region and entorhinal cortex: Inter subject variability and probability maps, 210, 2005, 343-352, Amunts K, Kedo O, Kindler M, Pieperhoff P, Mohlberg H, Shah NJ, Habel U, Schneider F, Zilles K ©Springer Verlag, "With permission of Springer".
Figure 2: Cytoarchitecture of the mesial temporal lobe at the level of the body of the hippocampus (a), and its head (b). The hippocampus proper with its subdivisions Cornu ammonis, dentate gyrus, the HATA, the subicular complex and the entorhinal cortex are labelled by different colours. Note that cytoarchitectonic borders of the different subdivisions do not coincide with sulci in most cases.
Source: Figure 2 (minimally altered) "Springer Anat Embryol, Cytoarchitectonic mapping of the human amygdala, hippocampal region and entorhinal cortex: Intersubject variability and probability maps, 210, 2005, 343-352, Amunts K, Kedo O, Kindler M, Pieperhoff P, Mohlberg H, Shah NJ, Habel U, Schneider F, Zilles K ©Springer Verlag, "With permission of Springer".
Amunts K, Kedo O, Kindler M, Pieperhoff P, Mohlberg H, et al. (2005) Cytoarchitectonic mapping of the human amygdala, hippocampal region and entorhinal cortex: Intersubject variability and probability maps. Anat Embryol 210: 343-352.
Yilmazer-Hanke DM, Wolf HK, Schramm J, Elger CE, Wiestler OD, et al. (2000) Subregional pathology of the amygdala complex and entorhinal region in surgical specimens from patients with pharmacoresistant temporal lobe epilepsy. J Neuropathol Exp Neurol 59: 907-920.
Graebenitz S, Kedo O, Speckmann EJ, Gorji A, Panneck H, et al. (2011) Interictal-like network activity and receptor expression in the epileptic human lateral amygdala. Brain 134: 2929-2947.
Adolphs R, Tranel D, Buchanan TW (2005) Amygdala damage impairs emotional memory for gist but not details of complex stimuli. Nat Neurosci 8: 512-518.
Klumpers F, Morgan B, Terburg D, Stein DJ, van Honk J (2015) Impaired acquisition of classically conditioned fear-potentiated startle reflexes in humans with focal bilateral basolateral amygdala damage. Soc Cogn Affect Neurosci 10: 1161-1168.