Cognition Workshop 02/09: Dr. Angela Radulescu
Towards naturalistic reinforcement learning in health and disease
Adaptive decision-making relies on our ability to organize experience into useful representations of the environment. This ability is critical in the real world: each person’s experience is dynamic and continuous, and no two situations we encounter are exactly the same. In this talk, I will first show that attention and memory contribute to inferring a set of features of the environment relevant for learning and decision-making (i.e. a “state representation”). I will then present results from ongoing work attempting to understand how such inference can take place in naturalistic environments. One line of work leverages virtual reality in combination with eye-tracking to study what features of naturalistic scenes guide goal-directed search. A second study examines the role of language in providing a prior for which features are relevant for decision-making. And a third thread focuses on how mood biases attention to different features of a decision. I will conclude with a discussion of the potential of naturalistic reinforcement learning as a model of mental health dynamics.
Cognition Workshop 1/26: Andrew Stier
Cognition Workshop 01/12: Dr. Mina Cikara
Causes and consequences of coalitional cognition
Cognition Workshop 12/01: Dr. Rebecca Keogh
Understanding and measuring visual imagery in congenital aphantasia (absent visual imagery) and it’s relation to other cognitive functions
Visual imagery is our ability to ‘see with the mind’s eye’ and the vividness with which people report being able to visualise varies substantially with some people reporting incredibly strong lifelike imagery while others report very weak imagery. A recently identified group (congenital aphantasia) report not experiencing any visual imagery at all. Due to its inherently private nature, one of the main hurdles to overcome in visual imagery research is objectively and reliably measuring individual differences in the ability to visualise. In my presentation I will report on some behavioural (binocular rivalry) and physiological (skin conductance and pupillometry) measures that can be used to index visual imagery strength in the general population, as well as the lack of visual imagery in congenital aphantasia. I will then also discuss how cortical excitability might drive individual differences in visual imagery strength, touching on our recent findings that show that a less excitable visual cortex produces the strongest visual imagery. Lastly, I will talk about how individual differences in visual imagery ability may influence a range of cognitive functions, specifically assessing the relationship between visual imagery and memory, in congenital aphantasia.
Cognition Workshop 11/17: Dr. Emily Cowan
How consolidation supports adaptive memories
We rely on our ability to recall the past to guide behavior in the present. However, since we cannot remember everything we encounter, it is adaptive for memory systems to prioritize retaining salient, goal-relevant information. Memories are thought to be stabilized in the brain as they become supported by distributed neocortical networks, facilitated by interactions between the hippocampus and cortex, particularly during periods of sleep. My research focuses on understanding the adaptive nature of consolidation processes, examining how consolidation not only prioritizes the retention of goal-relevant memories, but also reorganizes the way memories are represented within and across brain regions. Through such transformation, memories for related but distinct experiences can become integrated, leading to an abstracted trace that can be flexibly generalized to future experiences. In this talk I’ll present three studies examining how consolidation supports such adaptive prioritization and transformation processes, using behavioral measures and functional neuroimaging methods including task-based and resting-state functional connectivity and multivariate pattern analyses. I’ll present data showing sleep-dependent changes in the organization of memories in cortical regions and along the long-axis of the hippocampus, as well as work examining the scale of cortical regions that undergo such experience-dependent changes in service of selectively retaining novel information.
Cognition Workshop 11/3: Max Kramer & Andrew Savoy
What makes something memorable?: Analyzing the Memorability of Objects
Max Kramer
A growing body of research has demonstrated that certain stimuli are consistently remembered more often than others, even across large heterogeneous populations (Isola et al, 2011), leading many to ask, “what makes something memorable?” This consistency in what is remembered and what is forgotten has been hypothesized to reflect an intrinsic and measurable property of stimuli known as memorability (Bainbridge, 2019). In attempting to determine why we remember certain things and forget others, some researchers have hypothesized that the most memorable stimuli are the most atypical or distinctive (Valentine, 1991) while others suggest that the most typical items are most often remembered (Bainbridge, Dilks, & Oliva, 2017; Bainbridge & Rissman, 2018). Here, we examine THINGS, a hierarchical naturalistic object image database that systematically samples all concrete object concepts to determine whether the most typical or atypical items are most often remembered. We collect behavioral ratings of memorability from 13,946 AMT participants to compare to three different types of typicality ratings. We collect behavioral ratings of typicality to capture human intuition, similarity scores across the dimensions of an object space associated with THINGS, and similarities across features in a deep neural network. We find a spread of memorability that persists across all levels of THINGS and determine that there is a bias towards the most typical items being most often remembered, though there are counterexamples across the dataset. These results run counter to decades of research in memory, suggesting potential targets for future analyses.
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Perception and evaluation of courtship song in female songbirds during mate choice
Andrew Savoy
Mate choice is a complex psychological and behavioral process. It is also a central agent of the evolutionary theory of sexual selection. Insights from cognitive neuroscience are essential for understanding mate choice but are largely absent from studies of it. I study courtship display preferences and the corresponding neural signals of perception and evaluation. For this workshop I will present my rationale and methodology for testing two hypotheses pertaining female zebra finch responses to courtship song—one regarding temporal regularity in song and the other regarding song familiarity. This research has the potential to valuably extend the scope of our knowledge about sexual selection mechanisms while also deepening our neurobiological understanding of fundamental cognitive processes.
Cognition Workshop 10/20: Anna Corriveau
Connectome stability and typicality as markers of cognitive performance
Although sustained attention and working memory are essential to daily life, individual abilities vary. Whole-brain fMRI functional connectivity is a useful tool for building brain-based markers of cognition and has been used to identify network models of sustained attention (Rosenberg et al., 2016) and working memory (Avery et al., 2020). Further, there is evidence that features of whole-brain functional connectivity patterns, or connectomes, are related to brain function (Kaufmann et al., 2017; Vanderwal et al., 2021). Here, we define three connectome features—stability, typicality, and discriminability—that characterize connectome similarity with oneself and within a group. We then test the extent to which these features predict sustained attention and working memory task performance in three independent datasets (total N=421). Results suggest that individuals with more stable (i.e., similar to oneself across fMRI runs) and typical (i.e., similar to the group-average) connectomes perform better on these tasks. These results demonstrate the utility of including whole-brain connectome features in developing predictive models of cognitive abilities such as sustained attention and working memory.
Cognition Workshop 10/6: Dr. Michael A. Cohen
What is the bandwidth of perceptual experience? Evidence from virtual reality
How much information are we aware of in the visual world? While this question appears rather simple, answering it has been remarkably difficult and extremely controversial. Traditionally, researchers examine the limits of perceptual experience by changing individual items in a scene and seeing how often observers notice those changes (e.g., failing to notice a bowl disappearing/changing). Here, we took a different approach and asked how much we could alter an entire scene before observers noticed those global alterations. Specifically, we used a combination of standard psychophysics (i.e., computer displays) and gaze-contingent virtual reality (i.e., VR) to alter the scenes in one of two ways: 1) desaturating the periphery to render it entirely in black and white or 2) scrambling the periphery so much that no object could be detected or identified. Surprisingly, we found that observers routinely failed to notice drastic changes to that scene (e.g., presenting only 5% of the world in color while the rest was black and white, completely scrambling the periphery of a scene, etc.). Together, these results suggest that perceptual experience may be remarkably impoverished and that our intuitive sense of a detailed, colorful world is surprisingly incorrect.
Cognition Workshop 6/2: Dr. Jonathan Phillips
How we know what not to think