The Amygdaloid Nuclear Complex: Anatomic Study of the Human Amygdala

158 Pages·2016·20.85 MB·English

by  Vincent Di Marino

Vincent Di Marino
Yves Etienne
Maurice Niddam
The Amygdaloid
Nuclear Complex
Anatomic Study of
the Human Amygdala
123
The Amygdaloid Nuclear Complex

Vincent Di Marino
Yves Etienne (cid:129) Maurice Niddam
The Amygdaloid Nuclear
Complex
Anatomic Study of the Human Amygdala
Vincent Di Marino Maurice Niddam
Faculté de médecine Unité SAMU 13, Centre 15
Marseille Hôpital de la Timone
France Marseille
France
Yves Etienne
Unité de médecine légale
Hôpital de la Timone
Marseille
France
ISBN 978-3-319-23242-3 ISBN 978-3-319-23243-0 (eBook)
DOI 10.1007/978-3-319-23243-0
Library of Congress Control Number: 2015953156
Springer Cham Heidelberg New York Dordrecht London
© Springer International Publishing Switzerland 2016
This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is
concerned, specifi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction
on microfi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation,
computer software, or by similar or dissimilar methodology now known or hereafter developed.
T he use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not
imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and
regulations and therefore free for general use.
The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed
to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty,
express or implied, with respect to the material contained herein or for any errors or omissions that may have been
made.
Printed on acid-free paper
Springer International Publishing AG Switzerland is part of Springer Science+Business Media (www.springer.com)
To our beloved wives, our dear children and our adorable grandchildren
To all the neuroscientists and neuroanatomists of the world

Auth ors
Vincent Di Marino is emeritus professor of anatomy at the Aix Marseille University (AMU),
Faculty of Medicine; former director of the Kidney Transplantation Center of the Sainte-
Marguerite Hospital; and former director of the Laboratory of Anatomy at the Faculty of
Medicine, Marseille, France. Currently, his research topics are focused on the central nervous
system and the pelvis.
Faculté de Médecine de Marseille
27 Boulevard Jean Moulin
13385 Marseille Cedex 5
France
([email protected]).
Yves Etienne is forensic scientist, doctor of medicine, former assistant of anatomy, former
house physician in the hospitals of sanitary region and consulting practitioner in the Unit of
Forensic Medicine in the Timone Hospital (Marseille, France).
Unité de Médecine Légale
Hôpital de la Timone
264 Rue Saint-Pierre
13385 Marseille Cedex 5
Maurice Niddam is forensic scientist, doctor of medicine, former assistant of anatomy, coordi-
nating doctor of a medical center and regulating doctor of the Emergency Medical Service
(SAMU 13, Center 15) in the Timone Hospital (Marseille, France).
Unité SAMU 13, Centre 15
Hôpital de la Timone
264 Rue Saint Pierre
13385 Marseille Cedex 5
vii

Foreword
The amygdala is a small distinct brain structure, located in the anteromedial part of the tempo-
ral lobe. Variably designated as a “corpus”, a “complex” or a “nucleus”, depending on the
degree of importance its particular structure has inspired, this, admittedly small quantity of
brain tissue, is made up of islets of gray matter and weighs 1 g. It is a basal brain nucleus that
came to “glide” along the limbic cortex and appears to have perched on top of the hippocam-
pus. In contrast to other structures comprising the limbic system, the functional identity of the
amygdala is clear. It is the nodal point of our emotional life, it controls autonomic functions
and their expression and plays a role in the processing of olfactory and auditory stimuli.
T he physiology of the amygdala was initially studied in animals, mainly rats. Until the
advent of functional imaging, there was no data available allowing to conclude that it had a
similar function in humans, all the more since its size varies between species. The role that the
amygdala plays in temporal epilepsy was discovered during the fi rst studies with intracerebral
electrodes, performed by Talairach and Bancaud on patients with seizures, in the context of
operative management. From the outset, the amygdala was proven to be very closely linked to
the hippocampus, both during the interictal state, as well as at the outset of epileptic activity.
The bidirectional character of these connections has also become a marker of epileptogenic
foci in cases of medial temporal epilepsy (studies of Buser and Bancaud in 1983). The spec-
trum of clinical signs related to the involvement of the amygdala was identifi ed later. The
group of Talairach and Bancaud fi rst demonstrated the correlation with oro-alimentary autom-
atisms, then Gloor (this particular neurophysiologist, working at the Neurologic Institute of
Montreal, presented his thesis regarding the connections of the amygdala in 1957) demon-
strated the association with experiences of “déjà vu” and paroxysmal memory recollections.
Autonomic manifestations (heart rhythm acceleration, piloerection) and also emotional ones
(anxiety, fear) have been clearly associated with paroxysmal discharges from the amygdala.
Electrical stimulation of the amygdala results in reproduction of these same symptoms, espe-
cially “déjà vu” experiences. This last fact illustrates its importance in the mechanisms of
memory, in combination with the anterior hippocampus and the entorhinal cortex, especially
with regard to emotional memory or the infl uence of emotions in memory encoding.
Functional imaging has majestically demonstrated the role of the amygdala in encoding
negative emotions and especially its specifi city in deciphering the emotional expression of the
human face (Dolan). The team of Joseph Ledoux, having elucidated the functional circuitry of
fear and its storage in memory (consolidation and extinction of fearful memories, studies by
the Quirk team) in the rat, was also the one to demonstrate in humans, by means of functional
MRI, the interactions between the median prefrontal cortex of the cingulate gyrus and the
amygdala in regulating the response to a menace. All actual studies in the area of “affective”
neurosciences report activation of the amygdala, which has become the cerebral “center of
fear”. However, just as all sorts of amygdalar stimulations do not result in emotional modifi ca-
tions, all patients with Urbach-Wiethe disease (a genetic disease characterized by calcifi ca-
tions of the amygdala bilaterally) do not manifest with behavioral alterations, nor do they
exhibit a much different judgement as regards emotionally charged facial expressions, com-
pared to a control population (Siebert et al. 2003). These observations underline a certain
ix