Sensory input

…that brains continuously anticipate sensory input and update internal models based on prediction errors. In this talk, I will present converging evidence for the computational mechanisms underlying this framework across human neuroscience and deep neural networks. I will begin with recent work showing that large-scale distributed prediction-error encoding in the human brain directly predicts how sensory representations reorganize through predictive learning. I will then turn to PredNet, a popular predictive coding in

The relationship between vergence and accommodation remains relatively unexplored. The frequent co-occurrence of non-strabismic accommodation and vergence disorders suggests a link between the two processes. Experimental data also reveal that vergence and accommodation have reciprocal effects, where their reflexes influence each other mutually. According to previous findings, chromatic aberration (CA) plays a key role in the learning of accommodation, with the magnitude and direction of defocus being indicated by the relative contrasts detected by the long, medium, and short wavelength cones i

Behaviourally relevant sensory input is routinely transmitted and processed in biological networks, despite perpetual perceptually unrelated external, and spontaneously generated internal activity. Such activity has traditionally been understood as noise. In feed-forward networks, such noise can pose a challenge, because disambiguating stimulus-evoked activity and noise in deeper layers becomes increasingly difficult, for example in pattern classification tasks. On the other hand, the beneficial effects of noise for stochastic regularization and preventing co-adaptation were recognized in deep

…nervous system on multiple levels from sensory input to activity to motion: (1) projection patterns, connectivity, and muscle innervation within and across muscle segments; (2) swimming behavio

Despite decades of meticulous classification of spinal subtypes involved in central pattern generation (CPG), the synaptic architecture and mechanisms underlying locomotion remain elusive. We recently proposed a random network model, based on balanced excitation/inhibition, termed the Balanced Sequence Generator (BSG). This model recapitulated the rhythmic sequences observed in the cord and accommodated multi-functionality critical to CPGs. However, it did not include or address the diversity of spinal cell types. Here, we present a new approach that expands the BSG-framework to reconcile netw

…This involves integrating sensory input, managing competing motivational states, and drawing on past experiences to anticipate future outcomes. While traditional models attribute this complexity to interactions between the mesocorticolimbic system and hypothalamic centers, the specific nodes of integration have remained elusive. Recent research, including our own, sheds light on the midline thalamus's overlooked role in this process. We propose that the midline t

…motor actions directly influence sensory input on short timescales, and higher level information about goals and i

…of agency can affect the intensity of sensory input because we predict the input from our motor intention. However, my research has found that the sense of agency plays more roles than just predictions. It enhances perceptual processes of sensory input and potentially helps to harvest more information about the link between the external wo

Neurons in the rodent hippocampus appear to encode the position of the animal in physical space during movement. Individual ``place cells'' fire in restricted sub-regions of an environment, a feature often taken as evidence that the hippocampus encodes a map of space that subserves navigation. But these same neurons exhibit complex responses to many other variables that defy explanation by position alone, and the hippocampus is known to be more broadly critical for memory formation. Here we elaborate and test a theory of hippocampal coding which produces place cells as a general consequence of

The availability and scale of synapse-resolution connectomes containing the wiring of neural systems has grown rapidly in recent years. In order to exploit these rich datasets and extract neural circuit mechanisms underlying behavior, scalable connectome analysis tools capable of predicting information routing principles in circuit pathways are necessary. Current methods to extract neurons mediating information flow only consider a limited set of pathway lengths and do not scale to large connectome datasets. Here, we develop an efficient framework to identify such bottlenecks in pathways betwe

We hardly notice when there is a speck on our glasses, the obstructed visual information seems to be magically filled in. The mechanistic basis for this fundamental perceptual phenomenon has, however, remained obscure. What enables neurons in the visual system to respond to context when the stimulus is not available? While feedforward information drives the activity in cortex, feedback information is thought to provide contextual signals that are merely modulatory. We have made the discovery that mouse primary visual cortical neurons are strongly driven by feedback projections from higher visu

…continuously inhibits predictable sensory input, ensuring a preferential processing of surprising elements. A central aspect of this view on cortical computation is its hierarchical connectivity, involving recurrent message passing between excitatory bottom-up signals and inhibitory top-down feedback. Here we use computational modelling to demonstrate that such architectural hard-wiring is not necessary. Rather, predictive coding is shown to emerge as a consequence of energy efficien

…nuclei, are essential for receiving sensory input and for transmitting motor outputs to the body. These nucelii are critical relay stations which process incoming information and convert these signals to outgoing action potentials which regulate immune system functions. Thus, reflex neural circuits maintain parameters of immunological physiology within a narrow range optimal for health. Advances in neuroscience and immunology using optogenetics, pharm

…structure, can be modulated by sensory input and behaviour, and bears critical signatures of the underlying network dynamics and computations. However, current methods for characterising neural variability are primarily geared towards sensory coding in the laboratory: they require trials with repeatable experimental stimuli and behavioural covariates. In additi

Perception of object motion is fundamentally multisensory, yet little is known about similarities and differences in the computations that give rise to our experience across senses. Insight can be provided by examining auditory motion processing in early blind individuals. In those who become blind early in life, the ‘visual’ motion area hMT+ responds to auditory motion. Meanwhile, the planum temporale, associated with auditory motion in sighted individuals, shows reduced selectivity for auditory motion, suggesting competition between cortical areas for functional role. According to the metamo

…Impaired sensory input or abnormal experiences can have long-term negative consequences on brain health. We seek to define the precise synaptic aberrations caused by abnormal visual experiences early in life, and how these can be remedied through viral, genetic and environmental approaches. Resulting knowledge will contribute to the development of new approaches to mitigate nervous system damage caused by abnormal early life experience.

…understand how the timing precision of sensory input structures locomotor output. My lab studies the flight behavior of the fruit fly, Drosophila melanogaster, combining powerful genetic tools available for labeling and manipulating neural circuits with cutting-edge imaging in awake, behaving animals. This work has the potential to fundamentally reshape understanding of the evolution of insect flight, as well as highlight the tremendous importance of timing in the context of locomotion. Timing is crucial to the n