The temporal structure of perceptual experience
The perception of dynamically changing signals, the very basis of listening to language or music, or seeing naturalistic visual scenes, requires an analysis of the temporal information that forms (part of) the basis of such signals. What are the temporal primitives that underlie their perceptual analysis? How is incoming information temporally “sampled”? What type of temporal information is necessary to experience, say, rhythm, or syllable duration, or temporal intervals, or change in a sequence? Previous research suggests that human perceptual systems may optimize their processing by operating within specific temporal ranges, instead of in a unitary way across a continuum of temporal variation. We aim to identify the temporal building blocks that underlie perception and cognition, from the perspective that these building blocks are part of the operating system of the mind/brain that is provided by neurophysiological principles.
Projects
Are you in sync with yourself? Coordination of speech production and perception
In this project we test the influence of rhythmic speech production on speech perception. Auditory perception has been shown to utilize temporal predictions from the motor system to increase its performance (Arnal, & Giraud, 2012; Merchant, & Yarrow, 2016).
Computational Trajectories in artificial and human audition
Audition involves a deep temporal hierarchy of transformations supporting capacities such as speech and music perception. How are representations structured throughout the auditory system?
Metric biases in body and object size representations
The body is our primary interface with the world: it allows us to gather inputs from the outside, to build a representation of the world, to act and directly manipulate the environment. However, we do not perceive our body accurately.
Neural basis of memory for temporal order
Remembering the order of events is critical for everyday functioning. For instance, during a traffic accident it is important to know and to remember whether the traffic light turned from red to green or from green to red. Our ability to track temporal order generally declines with age, and is impaired in patients with neurodegenerative diseases, such as Alzheimer disease. What brain mechanisms support the capacity to encode temporal order?
The Persistence of Time
The processing of temporal information ranging from tens to hundreds of milliseconds is essential for surviving and for daily behaviors such as speech perception, music appreciation, dancing, performing sports, driving a car, etc. In this project my goal is to understand how the central nervous system tracks time. By using a combination of Electroencephalography, Psychophysics, and Eye-Tracking I aim at gaining new insights on how the human brain perceives time.
Apparent Motion
As early as 1912, Max Wertheimer reported in his famous paper on Gestalt psychology that two individual shapes may be perceived as a moving object if they are presented one after the other within a short time span. This phenomenon is called apparent motion.
Body perception
The body is our primary interface with the world: it allows us to gather inputs from the outside, to build a representation of the world, to act and directly manipulate the environment. However, we do not perceive our body accurately.
Cortical hierarchy of memories
“Perception is never purely in the present–it has to draw on experience of the past.” O. Sacks illustrates a grounding principle in cognitive neuroscience: Eyes are not vision. Instead, seeing is an inferential process, with the brain integrating incoming with past sensory information.
Beautiful sounds across species: How do birdsong and human music drive their listeners’ emotions?
For thousands of years people have admired the beauty of birdsong. But scientific understanding of this phenomenon is still restricted to studying learning and production mechanisms, as well as ecological function (how songs are used to attract mates and to defend territories).
Studying the neurocognitive processes behind the flow of consciousness
To create a continuous conscious percept, our brain is concurrently carrying out multiple tasks: sampling sensory information, predicting upcoming events, storing long-term memories, maintaining and reactivating information from the past, etc.
How space and perceived size are implemented in the brain
Visual perception is subjective and varies across individuals e.g., the physical size of an object is perceived differently across subjects. Where does this variability come from? We are investigating the role that short-range structural and functional connections plays in our subjective experience of space and perceived size.
Visual and somatosensory influence on metric biases in body representation
We do not perceive our body, and in particular our hands, accurately i.e., hands are distorted in their width and length. This phenomenon is observed in healthy individuals as well as in neurological and psychiatric disorders. What explains those distortions in the body representation?
The effect of implicit segmentation on perceived rate of continuous speech
Humans are able to spontaneously and rapidly extract information about the temporal structure of event sequences (Maheu et al. 2019). Statistical learning is one mechanism by which the brain is able to segment structured sequences, such as continuous speech, into meaningful units – even when the only cues to locating word boundaries lie in the transitional probabilities between individual syllables (Saffran et al. 1996, Aslin et al. 1998). We set out to investigate the perceptual consequences of this automatic and implicit segmentation process.
Uncertainty parameters in temporal expectancy
In everyday life, the human brain is confronted with information that implies certainty but that is in fact probabilistic by nature. For example, a train scheduled to arrive at a remote station at 12:15 might be canceled, and even if it reaches the station, it may arrive too early or too late. At a shorter timescale, in sports, a boxer's jab illustrates the point: is the puch coming at all? And if it is coming, when will it hit?
Visual space perception
How and why space ‘feels’ the way it does i.e., extended and structured? What is the neural process that supports this experience? In collaboration with Andrew Haun and Giulio Tononi (University of Wisconsin-Madison), we are investigating the neural mechanisms underlying our subjective experience of visual space.
Brain inspired consciousness
Recent developments in artificial intelligence (AI) have revived the possibility that we could endow machines with all the higher-order cognitive functions that characterize the mind of non-human and human primates. Much of this optimism derives from the achievements of contemporary artificial neural networks, which are equal to or even outperform humans in mundane and computationally demanding tasks like image classification