All Neural Dynamics Forum talks during Winter 2021 will take place online through Zoom, details as below.
Meeting ID: 932 7630 6396
Password: 815933
https://zoom.us/s/93276306396
1PM March 26th – Steve Brown (University of Zurich)
Cellular and circuit-based mechanisms underlying the daily regulation of sleep
“Mammalian sleep and wake follows a complex daily pattern influenced by both a circadian clock controlling vigilance according to time of day, and a sleep homeostat controlling vigilance according to prior wake history. In this lecture, we shall consider mechanisms underlying both central and local control of these processes, and how they in turn intimately control global metabolism.”
1PM March 19th – Yaara Erez (University of Cambridge)
Towards personalised neuroimaging in neurosurgery: linking brain structure and function
The importance of quality of life of patients following neurosurgery for brain tumors has been increasingly recognized in recent years. Emphasizing the balance between oncological and functional outcome, an emerging discipline at the forefront of research and patient care focuses on cognitive function. In current surgical standard practice, focal electrical stimulation on the exposed brain while patients are awake is used for mapping areas critical for motor function as well as language to prevent irreversible damage as a result of tissue removal. However, some cognitive functions are harder to map with standard stimulation alone. In the talk, I will present my work aimed at developing techniques and tools for mapping cognitive function in neurosurgery. I will focus on a particularly challenging aspect of cognition – executive functions – how we set and achieve goals, make plans, and prioritize tasks, which are essential to all aspects of our everyday life. Because of the complex nature of these functions and the distributed neural systems that support them, there are currently no established techniques for their functional mapping in neurosurgery. I will introduce a novel method for mapping executive function during awake neurosurgery using electrocorticography (ECOG) – recording directly from the surface of the brain – while patients perform cognitive tasks. I will show evidence for the feasibility and utility of this method as a first step towards establishing its foundations. Critical to bridging the translational gap and bringing neuroimaging into use in neurosurgery is our understanding of the functional role of the neural networks associated with cognitive functions and our ability to identify them in individuals. I will therefore present supporting findings for these using functional MRI (fMRI) data in healthy human volunteers. Finally, I will discuss some open questions related to developing neuroimaging tools for personalised medicine in neurosurgery.
1PM March 12th – Alexandra Constantinescu (UCL)
How do our brains form maps of the world?
Navigating our mental world is thought to be similar to navigating in the real world. In this talk, I will present behavioural and fMRI studies investigating how spatial and non-spatial memories are organized into 2D cognitive maps using grid cell-like codes in the entorhinal and medial prefrontal cortices. First, I will show a paradigm for navigation in an abstract “bird space”. Second, I will present how humans can learn long lists of words using the memory palace technique and a virtual reality task inspired by Harry Potter. And third, I will talk about a new method we’re developing for analysing human grid-like codes in more detail, using a big data approach and 7T submillimeter fMRI. Our findings have implications in understanding the remarkable capacity of humans to generalize experiences to novel situations.
1PM March 5th – Narender Ramnani (Royal Holloway)
Cerebellum and Cognition
The cerebellum is well-known for its contribution to the control of skilled movement. The mechanisms include connectivity with the motor system and the ability of it’s remarkable circuitry to store motor memories, including those relating to simple conditioned motor responses acquired through Pavlovian conditioning. However, some cerebellar circuitry communicates with the prefrontal cortex – including areas of that have important roles in cognitive function but little to do with motor control. In this lecture I draw from theoretical neurobiology, anatomy, brain evolution and neuroimaging to address the ways in which cerebellar circuits might contribute to the skilled execution of cognitive operations, such as the instrumental learning of contingencies that link decisions with their antecedents and consequences.
2PM February 26th – Keith Doelling (Institut Pasteur in Paris)
Temporal prediction of natural rhythms in speech and music
The ability to predict the onset of future events is a critical feature for survival. Knowing in advance when some stimulus might occur improves our ability to detect, process and react to it. The neuroscientific field has broken down temporal prediction into two separate and distinct mechanisms: interval timing, the measurement and prediction of single time intervals, and rhythmic timing, the synchronization with repeated sequential intervals. This talk will probe this formulation by asking how far it can get us when dealing with realistic stimuli. Rarely in the natural world (even in music) are rhythms perfectly isochronous and rarer still are temporal intervals presented in isolation. Here we test the extension, particularly, of rhythmic processing models into more naturalistic settings in two parts. First, I will show in a series of studies that neural responses to naturalistic stimuli like speech and music are well modeled as an oscillator synchronized to quasi-rhythmic input. Second, I will present work comparing such a model with behavioral responses of participants to ambiguous rhythms, suggesting that a neural oscillator may act as a kind of rhythmic prior to improve sensory perception of quasi-rhythmic stimuli. Together, the work will present a clear direction for the study of temporal prediction in more realistic environments. It will highlight computational modeling as well as behavioral research as a critical avenue for the elucidation of neural mechanisms underlying the temporal prediction of music and of the environment at-large.
12 PM February 12th – Oliver J Robinson (UCL)
The translational cognitive neuroscience of anxiety.
Anxiety can be a normal adaptive process, but it can also become a clinical state. At both ends of the spectrum anxiety significantly alters the ways individuals make decisions and behave. However, our understanding of the mechanisms underlying such symptoms is at present limited and does not contribute to treatment development or clinical decision-making. In this talk I will outline our recent work which attempts to better understand anxiety through a combination of computational modelling of behaviour and neuroimaging of adaptive and pathological anxiety.
1PM January 29th – Anil Seth (University of Sussex)
Consciousness, complexity, and hallucination
What happens in the brain during hallucination, and how can the study of hallucination shed light on ‘normal’ conscious perception. I will describe a number of research projects applying neurodynamical analyses (e.g., complexity, Granger causality) and computational models to shed light on the brain basis of hallucinatory perception. These projects include analyses of human neuroimaging data recorded during the psychedelic state, stroboscopic-induced hallucinations, and the use of computational models of predictive perception to model diverse hallucinatory forms. I will contextualise these analyses within the framework of ‘computational neurophenomenology’ – the attempt to account for phenomenological properties of perceptual experience in terms of (models) of their underlying neural mechanisms.
1PM January 22nd – Daniel Bush (UCL)
Theta Oscillations and Phase Coding in the Mammalian Hippocampus
The mammalian hippocampus is implicated in spatial and episodic memory function. In the rodent, hippocampal network dynamics can be characterised by oscillatory activity in the 6-12Hz theta band during active behaviour, and in the 150-250Hz ripple band during quiescent waking and sleep. During these periods, hippocampal place cells encode behavioural trajectories on a compressed timescale as theta sweeps and replay events, respectively. I will present a series of MEG and intracranial EEG experiments showing that human hippocampal theta oscillations also play a role in spatial coding, functional connectivity and memory. Next, I will present theoretical work that describes how oscillatory activity can support the phase coding of information in the central nervous system. Finally, using rodent place cell recordings, I will demonstrate that the temporal code for location within a place field is preserved across different network states. In sum, these results indicate that the mammalian hippocampus consistently uses phase coding in the service of memory encoding and retrieval.
2PM January 15th – Robb Rutledge (Yale University)
A Computational and Neural Model for Mood Dynamics
The happiness of individuals is an important metric for societies, but we know little about how daily life events are aggregated into subjective feelings. We have shown that happiness depends on the history of rewards and expectations, a result we have now replicated in thousands of individuals using smartphone-based data collection and quantified in relation to major depression (including in our new smartphone app https://thehappinessproject.app). Using fMRI, we show how happiness relates to neural activity in the ventral striatum and ventromedial prefrontal cortex. Computational modelling shows precisely how feelings vary across individuals in relation to a wide variety of factors including expectations, intrinsic reward, social comparison, and reinforcement learning.