In Vivo Anatomical Segmentation of the Human Amygdala and Parcellation of Emotional Processing

147 Pages·2012·4.04 MB·English

Eugenia Solano-Castiella: In Vivo Anatomical Segmentation of the
Human Amygdala and Parcellation of Emotional Processing. Leipzig:
Max Planck Institute for Human Cognitive and Brain Sciences, 2011
(MPI Series in Human Cognitive and Brain Sciences; 135)
In vivo anatomical segmentation of the human amygdala and
parcellation of emotional processing
Impressum
Max Planck Institute for Human Cognitive and Brain Sciences, 2012
Diese Arbeit ist unter folgender Creative Commons-Lizenz lizenziert:
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ISBN 978-3-941504-19-6
In vivo anatomical segmentation of the human amygdala and
parcellation of emotional processing

Der Fakultät für Biowissenschaften, Pharmazie und Psychologie
der Universität Leipzig
genehmigte

D I S S E R T A T I O N

zur Erlangung des akademischen Grades

doctor rerum naturalium
(Dr. rer. nat.)

vorgelegt von

Eugenia Solano-Castiella, M.A.

geboren am 29. Dezember 1981 in Bilbao, Spain

Dekan: Prof. Dr. Matthias Müller

Gutachter: Prof. Dr. Robert Turner

Prof. Dr. Angela D. Friederici

Leipzig, den 11.08.2011

To my mentor Prof. Robert Turner who taught me everything about neurophysics.

To my family who taught me everything else:
To my grandmother Maria Gloria Castiella Acha, my grandmother, for her modern mind.
To my father, Eugenio Solano, for his sensitivity.
To my sister Begoña Solano for her support during critical situations and for her creativity.
To my sister Maria Solano for fantastic intellectual conversations.
To my sister Teresa Solano, for being a solid family bond, for her tireless listening, humility,
optimism and generosity.
To my brother Carlos Solano, for his incredible trust, practical mind and creativity.

To my great friends and colleagues having big brains and big hearts Robert Trampel, Bibek Dhital
and Markus Streicher for all their support, advice, guidance, care and sense of humor.

To Felix von Zwehl, for the wholehearted support, generosity and sense of humor.

This thesis is especially dedicated to my mother, Marian Castiella, who is the biggest fan of all her
children and has managed to understand them individually. None of us would be who we are now
without your wholehearted support. Thank you.
Acknowledgments

I would like to briefly thank those who have most influenced and contributed to my scientific
development in my time at the Max Planck Institute. First of all, I want to thank Prof. Robert Turner
for the trust he has put into me especially considering my background as a non physicist and also his
never ending guidance, support and encouragement he has given not only to me, but to all the
members of his group. I also want to thank Prof. Angela Friederici for her expert advice and support
and Prof. Gabriele Lohmann for her kindness and her expertise in clustering algorithms. Also, I
would like to thank Dr Hubertus Axer, who with his expertise and knowledge has helped me very
much, especially with the polarized light imaging study. Also, I very much appreciate Dr Torsten
Bullmann's efforts to provide the lab with fetal brains and the large contribution of Dr Martina
Brueckner with the studies.

I had the honor of working in a very collaborative working environment being surrounded by superb
scientist. Especially grateful I am to Dr Alfred Anwander, without whom the DTI technique for me
would still be a puzzle to me, and to Enrico Reimer, who in moments of panic always found ways to
getting the computer systems work. I am greatful to Dr. Robin Heidemann for helping me understand
DTI at 7 T as well as to Bibek Dithal who also had a remarkable contribution to the functional study
conducted in this thesis. In addition, I want to thank Markus Streicher for his help with phantoms and
his catching positive attitude and Dr Tom Fritz for helping me with the auditory stimuli used and for
unforgettable musical performances. I appreciate very much the help of Marcel Weiss on
segmentation tools. I am thankful to Dr Deborah Rivera and Rosie Wallis for proofreading on short
notice. I would also like to mention Dr Waltraud Stadler and Dr Andreja Bubic with whom I share
many memorable moments. I really appreciate the generous kindness of Borja Sicre in the last years.
I can´t forget to thank my school teacher Maria Robledo who found great potential in me as well as
my university teacher Dr Imanol Arregui, who has been an inspiration for me in neurology and
research. I also have to thank the good heart and work from Ziggi and Chris Becker. I am greatful to
Dr Mestres for helping me with the fMRI analysis. I would also like to thank Liane Voigt for all the
patience and help with the thesis university paper work. Thanks to the great help of Dr Andreas
Schäfer who is a fantastic person to work with I was able to develop the structural parcellation of the
amygdala. Also it has been fantastic to work with Dr Robert Trampel, whom I thank for his great
contribution during the different projects. Both scientists helped me have a better understanding of
MRI and the different MR sequences used.
Bibliographic details
Eugenia Solano-Castiella
In vivo anatomical segmentation of the human amygdala and parcellation of emotional
processing
Fakultät für Biowissenschaften, Pharmazie und Psychologie
Universität Leipzig
Dissertation
112 pages, 191 references 37 figures, 3 tables

The goal of this thesis is to parcellate the human amygdala in vivo and correlate its subregions with
their functional properties. Since the amygdala is involved in a range of emotions, their anatomical
specificity within the amygdala has become a target of functional imaging. Diffusion tensor imaging
(DTI) was used to robustly segment this grey matter area, enabling the consequent creation of
probabilistic maps. Polarized light imaging validated the DTI results ex vivo, demonstrating similar
regional orientations as those obtained with DTI. DTI of non-myelinated structures is atypical.
Therefore, DTI of non-myelinated fetal brain was performed to confirm that anisotropic water
diffusion can take place in brain areas even in the absence of myelin. These three studies have
revealed intrinsic tissue properties within the amygdala and have been able to provide, for the first
time in vivo, a segmentation of amygdala subregions. Using the high signal to noise ratio offered by
ultra-high field MRI at 7 Tesla, the combination of two conventional anatomical MR contrasts
enabled additional robust probabilistic maps of the amygdala to be formed. Finally, this work
explored the distribution of emotional functions within the amygdala with the aide of the
connectivity-based segmentations and the structural-based segmentations. This last work directly
correlated function with its anatomical substrate. In conclusion, this thesis provides the first
probabilistic maps of the amygdala in vivo, and has identified different emotional valences related to
the probabilistic maps achieved.
Contents
Preface...………………………………………………………………………………… 2
I Theoretical Background
Chapter 1. The amygdala: Anatomy, connectivity and function………………………… 3
Chapter 2. Magnetic resonance imaging (MRI) principles………………………………. 11
Chapter 3. Diffusion tensor imaging (DTI) principles…………………………………… 21
Chapter 4. Polarized Light Imaging (PLI).………………………………………………. 31
II Materials and Methods
Chapter 5 Experiment 1…………………………………………………………………. 37
Diffusion tensor imaging segments the human amygdala in vivo
Chapter 6. Experiment 2………………………………………………………………… 43
Polarized light imaging (PLI) of the human amygdala
Chapter 7. Experiment 3………………………………………………………………… 47
Diffusion tensor imaging (DTI) with a non-myelinated fetal brain
using ultra-high field MRI
Chapter 8. Experiment 4………………………………………………………………… 49
Parcellation of the human amygdala in vivo using ultra-high field MRI
Chapter 9. Experiment 5..……………………………………………………………….. 53
fMRI of the human amygdala using ultra-high field MRI.
Parcellation of emotional human non-linguistic sounds
III Results
Chapter 10. Experiment 1………………………………………………………………. 61
Experiment 2……………………………………………………………….. 70
Experiment 3……………………………………………………………….. 74
Experiment 4……………………………………………………………….. 79
Experiment 5……………………………………………………………….. 86
IV Final Conclusions……………………………………………………………………. 100
References……………………………………………………………………………….. 104