Cognition seminars

Over 60 years of research has established that medial temporal lobe structures, including the hippocampus and entorhinal cortex, are necessary for the formation of episodic memories (i.e. memories of specific personal events that occur in spatial and temporal context). While prior work to establish the neural mechanisms underlying episodic memory has largely focused on questions related spatial context, recently we have begun to investigate how these brain structures could be involved in encoding aspects of temporal context. In particular, we have focused on how medial entorhinal cortex, a structure well known for its role in spatial memory, may also be involved in encoding interval time. To answer this question we have developed an instrumental paradigm for head-fixed mice that requires both immobile interval timing and locomotion-dependent navigation behavior. By combining this behavioral paradigm with large-scale cellular resolution functional imaging and optogenetic-mediated inactivation, our results suggest that MEC is required for learning of interval timing behavior and that interval timing could be mediated through regular, sequential neural activity of a distinct subpopulation of neurons in MEC that encode elapsed time during periods of immobility (Heys and Dombeck, 2018; Heys et al, 2020; Issa et al., 2020). In this talk, I will discuss these findings and discuss our on-going work to investigate the principles underlying the role of medial temporal lobe structures in timing behavior and episodic memory.

How flexible are association cortices? I will present a series of fMRI experiments addressing this question by investigating individuals born without hands, who use their feet as effectors to perform everyday actions. These results suggest that computations in association cortices are abstracted from visuomotor features and experience, similarly to the visual -independence of the association networks in people born blind, highlighting these regions’ ability to compensate for experience in any specific modality. These findings also open new avenues to utilize effector-independence in the action system for motor rehabilitation.

Using Systems Neuroscience Approaches to Understand Motor Learning & Recovery Post-Stroke

Bilingualism and its link to cognition

I will discuss our recent evidence showing that information about abstract rules can be decoded from neuronal activity in primate visual cortex even in the absence of sensory stimulation. Furthermore, that rule information is greatest among neurons with the least visual activity and the weakest coupling to local neuronal networks. In addition, I will talk about recent developments in large-scale neurophysiological techniques in nonhuman primates.

Deciding whether two different face photographs or voice samples are from the same person represent fundamental challenges within applied settings. To date, most research has focussed on average performance in these tests, failing to consider individual differences and within-person consistency in responses. In the current studies, participants completed the same face or voice matching test on two separate occasions, allowing comparison of overall accuracy across the two timepoints as well as consistency in trial-level responses. In both experiments, participants were highly consistent in their performances. In addition, we demonstrated a large association between consistency and accuracy, with the most accurate participants also tending to be the most consistent. This is an important result for applied settings in which organisational groups of super-matchers are deployed in real-world contexts. Being able to reliably identify these high performers based upon only a single test informs regarding recruitment for law enforcement agencies worldwide.

My research uses a range of methods to better understand how the brain’s natural chemicals control complex behaviours, thoughts and perceptions. I also have a particular fascination about the factors that determine the contents of an individual’s conscious experience. In this talk I will present work that sits at the intersection of these two research areas looking at the role of different neurotransmitter systems in driving changes in conscious state. Specifically, I will discuss a series of studies using ambiguous stimuli to explore the neuropharmacological processes that underly alternations in perceptual awareness. By comparing different methods and neurotransmitter systems including: serotonin (psychedelics), noradrenaline (pupillometry) and Glutamate/GABA (Magnetic Resonance Spectroscopy MRS) we can start to tease apart the distinct role that different neurotransmitter systems play in coordinating conscious experience across time.

The cellular representations and computations that allow rodents to navigate in space have been described with beautiful precision. In this talk, I will show that some of these same computations can be found in humans doing tasks that appear very different from spatial navigation. I will describe some theory that allows us to think about spatial and non-spatial problems in the same framework, and I will try to use this theory to give a new perspective on the beautiful spatial computations that inspired it. The overall goal of this work is to find a framework where we can talk about complicated non-spatial inference problems with the same precision that is only currently available in space.

Behaviourism is dead. But what did the 'cognitive revolution' do with the leftover - the idea of 'mind' that nobody seems to want anything to do with, even philosophers. Is studying the brain the same as studying the mind ? Do you need to 'see' inside the brain to study the brain ? Or mind ? How does the tools of behaviourism help ?

Join us for a conversation on the neuroscience of music, composition and song writing!

Working memory (WM) is a fundamental human cognitive capacity that allows us to maintain and manipulate information stored for a short period of time in an active form. Thanks to a unique opportunity to record activity of neurons in humans during epilepsy monitoring we could test neuronal mechanisms of this cognitive capacity. We showed that firing rate of image selective neurons in Medial Temporal Lobe persists through maintenance periods of working memory task. This activity was behaviorally relevant and formed attractors in its state-space. Furthermore, we showed that firing rate of those neurons phase lock to ongoing slow-frequency oscillations. The properties of phase locking are dependent on memory content and load. During high memory loads, the phase of the oscillatory activity to which neurons phase lock provides information about memory content not available in the firing rate of the neurons.

The Brain Awareness Week by the Centre for Cognitive and Brain Sciences, IIT Gandhinagar spans across 7 days and invites you for a series of talks, panel discussions, competitions and workshops on topics ranging from 'Using songbirds to understand how the brain initiates movements' to 'Cognitive Science and UX in Game Design' by speakers from prestigious Indian and International institutes. Explore the marvels of the brain by joining us on 15th March. Free Registration.

I will present field experiments on vervet monkeys testing physical and social cognition, with a focus on social learning. The understanding of the emergence of cultural behaviours in animals has advanced significantly with contributions from complementary approaches: natural observations and controlled field experiments. Experiments with wild vervet monkeys highlight that monkeys are selective about ‘who’ they learn from socially and that they will abandon personal foraging preferences in favour of group norms new to them. The reported findings highlight the feasibility to study cognition under field conditions.

Initial social perceptions are often thought to reflect direct “read outs” of facial features. Instead, we outline a perspective whereby initial perceptions emerge from an automatic yet gradual process of negotiation between the perceptual cues inherent to a person (e.g., facial cues) and top-down social cognitive processes harbored within perceivers. This perspective argues that perceivers’ social-conceptual knowledge in particular can have a fundamental structuring role in perceptions, and thus how we think about social groups, emotions, or personality traits helps determine how we visually perceive them in other people. Integrative evidence from real-time behavioral paradigms (e.g., mouse-tracking), multivariate fMRI, and computational modeling will be discussed. Together, this work shows that the way we use facial cues to categorize other people into social groups (e.g., gender, race), perceive their emotion (e.g., anger), or infer their personality (e.g., trustworthiness) are all fundamentally shaped by prior social-conceptual knowledge and stereotypical assumptions. We find that these top-down impacts on initial perceptions are driven by the interplay of higher-order prefrontal regions involved in top-down predictions and lower-level fusiform regions involved in face processing. We argue that the perception of social categories, emotions, and traits from faces can all be conceived as resulting from an integrated system relying on domain-general cognitive properties. In this system, both visual and social cognitive processes are in a close exchange, and initial social perceptions emerge in part out of the structure of social-conceptual knowledge.