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CLINICAL NEUROANATOMY SEMINARS
Engage | Connect | Communicate
Primary progressive aphasia: a window into language neurobiology
Dr Stefano Cappa
31 May 2023
#CNStalk
Stefano F. Cappa received his M.D. at the University of Milano, where he completed his neurology training. He has held assistant professor and associate professor positions in Neurology and Neurological Rehabilitation at the University of Brescia. Since 1999 he has been a Professor of Neuropsychology at the Vita Salute S. Raffaele University in Milano, Italy and, from Nov 2000 to Nov 2009, Dean of Psychology. He is also the Director of the Neurology Department of S. Raffaele Turro Hospital, Milano, Italy. He has spent research periods at Boston University, at the Massachusetts Institute of Technology, at the University of California San Diego, the Medical Research Council Cyclotron Unit of Hammersmith Hospital in London and at the Max Planck Institut for Cognitive Neuroscience in Leipzig.
Zarin Machanda's research revolves around understanding the factors that shape the quality and development of social relationships among wild chimpanzees. Her work so far has focused mostly on the evolution of male-female relationships, male-male cooperation (especially cooperative hunting), and how chimpanzees use communication to mediate social relationships. Most recently, she has started a long-term project to study infant and juvenile chimpanzees and how they develop sex-typed adult behaviors. Zarin is the Director of Long-term Research at the Kibale Chimpanzee Project, an organization that for the last 30 years has conserved and protected the Kanyawara community of chimpanzees living in Kibale National Park, Uganda. She is also on the Board of the Kasiisi Project, a community development organization in Uganda that works with over 9000 school children living around Kibale National Park. Zarin holds a secondary appointment in the Department of Biology.
Visual hallucinations are a common and often distressing feature of Parkinson's disease; they are ephemeral and capricious, making them difficult to study but tend to be more prominent in dim illumination. Dr Angeliki Zarkali is a specialist registrar in Neurology with an interest in cognitive neurology and movement disorders. Her clinical and research interest is the aetiology, diagnosis and treatment of Parkinson's disease dementia and Dementia with Lewy Bodies.
Finding the network balance in Parkinson’s hallucinations
Dr Angeliki Zarkali
24 November 2022
#CNStalk
Involvement of the cerebellum in motor and emotional learning
Dr Dagmar Timmann-Braun
29 September 2022
#CNStalk
A major interest is the involvement of the human cerebellum in different forms of motor learning. We are interested in the cerebellum's contribution to acquisition and extinction processes. Questions addressed are whether the cerebellum is involved in particular forms of learning, which cerebellar areas are involved and what the mechanisms of cerebellar involvement are. Another interest is the role of the cerebellum in cognition. The main focus is the study of patients with defined cerebellar pathology. Localization of focal cerebellar lesions and extent of atrophy in cerebellar degeneration is defined based on high-resolution structural MRI. Lesion data is correlated with findings in neurophysiological and psychological experiments. In addition, functional MRI studies are performed using 3T and 7T MR scanners. Transcranial direct current Non-invasive brain stimulation (tDCS) modulates cerebellar function in healthy subjects and patients with cerebellar disease.
Magnetic Resonance Imaging (MRI) had brought about a revolution in the study of human brain function. Nowadays, hundreds of functional MRI studies are being published daily. In this talk, I will discuss the importance of the magnetic field strength of the MRI system for functional MRI specifically. I will give examples of what can be achieved with ultra-high field scanners, which are those that use magnets of 7 Tesla or higher, and I will discuss the possible clinical applications of these technological improvements.
The emergence of High order Hubs in the Human Connectome
Dr Fernando Santos
#CNStalk
Functional brain networks are often constructed by quantifying correlations between time series of activity of brain regions. Their topological structure includes nodes, edges, triangles, and even higher-dimensional objects. Topological data analysis (TDA) is the emerging framework to process data sets under this perspective. In parallel, topology has proven essential for understanding fundamental questions in physics. We report the discovery of topological phase transitions in functional brain networks by merging concepts from TDA, topology, geometry, physics, and network theory. We show that topological phase transitions occur when the Euler entropy has a singularity, which remarkably coincides with the emergence of multidimensional topological holes in the brain network. The geometric nature of the transitions can be interpreted, under certain hypotheses, as an extension of percolation to high-dimensional objects. Due to the universal character of phase transitions and noise robustness of TDA, our findings open perspectives toward establishing reliable topological and geometrical markers for group and possibly individual differences in functional brain network organisation.
Beyond group averages: using machine learning and big data to chart individual variability in mental disorders
Dr André Marquand @amarquand
#CNStalk
Neuroscience has truly transitioned into the era of big data, yet most analytical approaches still focus principally on detecting group level differences between clinical cohorts. Dr Marquand describes a series of machine learning techniques we have developed to move the field beyond this impasse, including normative modeling or ‘brain growth charting’ techniques that allow us to chart variability at the level of each individual person, providing a platform for precision stratification of mental disorders. Dr Marquand illustrates this discussion by showing applications in schizophrenia, autism, ADHD and bipolar disorder.
From the many who died from it, to those who suffered from it, to those who didn't even know they had it, and to those who never caught it, Covid-19 and its spread has impacted all of our lives. With the flurry of information floating around on the internet and on the television, let's take stock and hear from the experts and clinicians.
COVID-19 & the Brain: Insights from the Clinic
What we know and what we don't know
Dr Hamid Merdji (France) & Dr Harith Akram @HarithAkram (UK)
#CNStalk
Anatomo-functional organisation of the grasping network in the primate brain
Dr Elena BORRA @ElenaBorra1
#CNStalk
Cortical functions result from the conjoint activity of different, reciprocally connected areas working together as large-scale functionally specialized networks. In the macaque brain, neural tracers and functional data have provided evidence for functionally specialized large-scale cortical networks involving temporal, parietal, and frontal areas. One of these networks, the lateral grasping network, appears to play a primary role in controlling hand action organization and recognition. Available functional and tractograpy data suggest the existence of a human counterpart of this network.
Hedonia and eudaimonia:
Brain systems for thriving and surviving
Dr Morten L. Kringelbach
#CNStalk
For Aristotle, the goal of human life was to live well, to flourish, and to ultimately have a good life. These goals can be conceptualised as “eudaimonia”, a concept distinct from “hedonia” (pleasure). Many people would argue that the arts play a large role in their well-being and eudaimonia. Music in particular is a culturally ubiquitous phenomenon which brings joy and social bonding to listeners. Research has given insights into how the ‘sweet anticipation’ of music and other art forms can lead to pleasure, but a full understanding of their role in eudaimonia is still missing. What is clear is that anticipation and prediction are important for extracting meaning from our environment. In fleeting moments this may translate into both pleasure and pain, which over longer timescales can give rise to flourishing and suffering, providing meaning and purpose to life. I will discuss some of the evidence from neuroimaging and whole-brain modelling for the role of sex, drugs and music in helping orchestrating eudaimonia, and propose future strategies for exploring the deep remaining questions
There's an Elephant in the Room: What it takes to Imagine Something
Dr Alfredo Spagna @SpagnaPhD
#CNStalk
The dominant model of visual mental imagery stipulates that memories from the medial temporal lobe acquire sensory features in early visual areas. Yet, there is an elephant in the room. Well, actually, if we look carefully, there are multiple elephants in this room. The neuropsychological, neuroimaging (both PET and FMRI), and stimulation literature from the past thirty years has consistently refuted this model, and showed that high-level visual areas in the ventral pathways seem to be critical for mental imagery. I will share a brief overview of the imagery literature, starting with Penfield - 1938, and moving onto Levine and Farah - 1985 - then touching upon the early fMRI study of Mark D’Esposito - 1999 - and sequent neuroimaging evidence, and ending with a striking lesion study of an architect who lost the ability to imagine - Thorudottir et al., 2020. A common thread will arise: a node in the inferior temporal gyrus - i.e., the Fusiform Imagery Node - stands out as a key area for mental imagery. To conclude, a new model of mental imagery is delineated, one that attempts to fully reconcile the literature on visual mental imagery in humans and in nonhuman animals.
Shaping brain structure and function
Dr Sofie Valk @sofievalk
25 March 2021
#CNStalk
The organisation of the cerebral cortex has been proposed to be an important prerequisite for human cognition. We looked at how the genetic and environmental factors shape large-scale brain organisation in healthy adults. In the first study we evaluated the genetic basis of large-scale cortical organisation of thickness covariance using twin-models (Human Connectome Project) as well as cross-species comparisons (PRIME-DE). We found two organisational axes reflecting functional and evolutionary patterning. In a second study we assess the functional organisation and plasticity of the social brain. Whereas attention was associated with external, focused, functional processes, we found that theory of mind related to internal, ongoing, cognitive processes. Conversely, affective skills related to both processing modes. Next we studied longitudinal changes following 3-months of training (i) mindfulness-based attention and interoception, (ii) socio-affective skills, and (iii) socio-cognitive skills respectively (ReSource study). Contrasting the effect of each training module, we found diverging patterns of functional network reorganisation. Together, these studies establish the genetic basis and functional plasticity of natural axes in the cerebral cortex and so provide important insights into the organisation of human cognition.
The thalamus integrates the macro systems of the brain to facilitate complex adaptive brain dynamics
Dr James M Shine @jmacshine
#CNStalk
The thalamus is well-placed to arbitrate the interactions between distributed neural assemblies in the cerebral cortex. Different classes of thalamocortical connections are hypothesized to promote either feed-forward or feedback processing modes in the cerebral cortex. This activity can be conceptualized as emerging dynamically from an evolving attractor landscape, with the relative engagement of distinctly distributed circuits providing differing constraints over the manner in which brain state trajectories change over time. In addition, inputs to the distinct thalamic populations from the cerebellum and basal ganglia, respectively, are proposed to differentially shape the attractor landscape, and hence, the temporal evolution of cortical assemblies. The coordinated engagement of these neural macrosystems is then shown to share key characteristics with prominent models of cognition, attention and conscious awareness. In this way, the crucial role of the thalamus in mediating the distributed, multi-scale network organization of the central nervous system can be related to higher brain function.
Development of subject-specific representations of neuroanatomy via a domain-specific language
Dr. Antonia Machlouzarides-Shalit
#CNSPhDViva
Watch Antonia Machlouzarides-Shalit become a PhD whilst she defends her thesis before a panel of judges. In the field of brain mapping, she identified the need for a tool that is grounded in the detailed knowledge of individual variability of sulci. As such, she developed a new brain mapping tool called NeuroLang, which utilises the spatial geometry of the brain. By bridging classical neuroanatomy with computational brain mapping, she identifies and labels subject-specific sets of sulci, examines individual and group-level morphologies, and establishes a data-driven approach to quantifying sulcal stability.
Atlasing white matter connections in the living human brain
Dr. Katrine Rojkova
#CNSPhDViva
Watch Katrine Rojkova become a PhD whilst she defends her thesis before a panel of judges. Presenting on the mapping of white matter connections, Rojkova's atlas will strengthen the capacity of clinicians to further understand the mechanisms involved in brain recovery and plasticity, and assist in the diagnosis of disconnection or abnormality within specific tracts of individual patients with various brain disease.
Structural Connectivity of the Cerebral Cortex
Co-hosted by: Dr Hiromasa Takemura (Japan),
Dr Stephanie Forkel & Dr Michel Thiebaut de Schotten (France)
#CNScomms
CNSeminars joined forces with the journal, Brain Structure and Function (BSAF), and the Springer Neuroscience Network to host the first BSAF 'Structural Connectivity of the Cerebral Cortex' Special Issue symposium. Co-hosted by Dr Hiromasa Takamura, Dr Stephanie Forkel and Dr Michel Thiebaut de Schotten, this 2-day event featured 10 different experts who presented various topics related to structural connectivity followed by a brief Q&A.
The 5th Dementia - a documentary
Serene Meshel-Dillman
#CNSmovie
Serene Meshel-Dillman delivers a documentary on The 5th Dementia, a diverse band featuring former professionals who now struggle to remember anything at all due to illnesses: Alzheimer's, Dementia, Parkinson's. When the music starts, these men and women, leading lives with almost no social interaction, dive right into songs from their generation without a single page of sheet music. Memories otherwise entirely unreachable are unlocked. Through uniquely personal stories, from inspiring daily triumphs to the sobering toll of slow mental decline, viewers of The 5th Dementia Documentary will see an emotional, revealing look at this inexplicable phenomena. See the film's trailer and watch the Q&A with the filmmaker on the CNSeminars YouTube Channel.
More info here: www.the5thdementiadocumentary.com/ or on Twitter twitter.com/5thDementiaDoc
The use & misuse of in silico lesion-deficit mapping
Parashkev Nachev, University College London
#CNStalk
Once thought to require nothing more sophisticated than mass-univariate statistics, lesion-deficit mapping is increasingly recognized to be amongst the most complex problems in neuroscience. Its distinctive strength, inference to neural necessity, is paradoxically the source of its greatest vulnerability: dependence on the parameterisation of the lesioned brain as a whole, at least whereas nearly everywhere- the lesions are large in proportion to the mapped substrate. Such dependence violates the foundational assumptions of mass-univariate analysis, voiding its conclusions of all force. First demonstrated by combining simulated functional ground truths with real lesion data, it is a vulnerability some have tried to rectify through the same in silico approach, retaining the mass-univariate framework it has revealed to be critically deficient. Dr Nachev discusses what simulations can and cannot licitly do here, and sketches out a path to evaluating the high-dimensional multivariate models that lesion-deficit mapping will always require, whether we like it or not.
My Love Affair with the Brain: The Life and Science of Dr Marian Diamond
Gary Weimberg & Catherine Ryan
#CNSmovie
How can you not fall in love with a woman who carries around a preserved human brain inside a giant flowery hat box? Meet Dr Marian Diamond, a renowned academic and research scientist, and prepare to be smitten. Catherine Ryan and Gary Weimberg’s film follows this remarkable woman over a 5-year period and introduces the viewer to both her many scientific accomplishments and the warm, funny, and thoroughly charming woman herself, who describes her 60-year career researching the human brain as “pure joy.” See the film's trailer and watch the Q&A with the filmmakers on the CNSeminars YouTube Channel.
More info here: www.myloveaffairwiththebrain.com/RSMTp/ or https://lunaproductions.com/brain/
Study guides - From 5th grade to Nobel prize winner: https://lunaproductions.com/study-guide-brain/
SciAm on this film: https://blogs.scientificamerican.com/guest-blog/whats-the-best-way-to-talk-about-science/
This House believes that Russia has contributed the most to Asphasiology
For: Dr Olga Dragoy, Moscow, Russia
Against: Dr Leo Bonilha, South Carolina, USA
#CNSdebate
Hear two asphasiology experts, Dr Olga Dragoy and Dr Leo Bonilha, debate on whether Russia has contributed the most to this field of research. See which expert you believe won the debate.