His research focuses on blindness, which is both a limiting condition affecting many millions worldwide, and constitutes a unique model for answering fundamental questions in cognitive neuroscience. His lab's work ranges from basic science, querying brain plasticity and sensory integration, to technological developments, allowing the blind to be more independent and even “see” using sounds and touch similar to bats and dolphins (a.k.a. Sensory Substitution Devices, SSDs), and back to applying these devices in research.
The central hypothesis of the work is that visual areas can process sound and touch to a similar extent as they process vision, but only when subjects learn to fully extract the relevant information encoded by these alternative senses. He proposes that, with proper training, many (if not all) visual brain areas or network can change the type of sensory input it uses to retrieve behaviorally (task)-relevant information within a matter of weeks/months. He also suggest that visual-like selectivity might develop without any visual experience. If this is true, it can have far reaching implications also for clinical rehabilitation, which is the second major aim of his lab.
The main goal of his 'Neuronal Oscillations' research group is to understand how oscillatory activity shapes the functional architecture of the working brain during cognitive processing. While modulations of alpha band oscillations (8-13 Hz) reflect anticipatory top-down modulation, bottom-up processing is reflected by gamma band synchronization (30-100 Hz). Specifically, the core hypothesize states that neuronal communication is gated by inhibitory alpha oscillations in task-irrelevant regions, thus routing information to task-relevant regions. According to this framework the brain can be studied as a network by investigating cross-frequency interactions between gamma and alpha activity.
The research tools applied by the group include computational modeling, MEG, EEG combined with fMRI, EEG combined with TMS and intracranial recordings. These tools are applied to investigate and interpret data from humans and animals performing attention and memory tasks. Furthermore, the group investigates these mechanisms to understand the basis of attention problems in ADHD patients and the aging population.
His research is focused on the implementation of flexible adaptive behavior in the human brain, in particular on performance monitoring, learning from action outcomes and decision making. His work has contributed to the understanding of the functional roles of the posterior mesial frontal cortex in monitoring for changes in task demands and informative action outcomes, and in driving necessary adjustments.
This research is done in a multimodal fashion, including EEG, functional, structural and diffusion MRI, pharmacological challenges, imaging genetics, peripheral psychophysiology and computational modeling applied in healthy participants and patients with selected neurological and psychiatric disorders.
The work has great societal importance as it helps to understand how people detect their errors and unsuccessful actions, and how they compensate and remediate failures. Furthermore, it contributes to the understanding why and when errors are made.
His research focuses on the physiological, pharmacological and anatomical bases of synaptic transmission, with a particular emphasis on cellular substrates of pathological conditions in the Central Nervous System (CNS). Recent work focuses on the synaptic mechanisms in the sensory spinal cord and their plasticity during development and in experimental models of chronic pain, on the synaptic changes in the neocortex during ageing and Alzheimer’s disease, and on the impact of synaptic activity on the computational properties of neurons.
This research is done using a wide array of approaches, including electrophysiological recording in vivo (micro-optrodes) and in vitro (patch clamp in slices), multiphoton and other non-linear imaging techniques, time-resolved fluorescence microscopy, in vivo optogenetics, tissue-based biochemical analysis, neural tracing and immunocytochemistry, and computational approaches.
His work is aimed at understanding the molecular mechanisms of synaptic transmission, mainly focusing on presynaptic nerve terminals, employing a multidisciplinary approach ranging from molecules to behavior: molecular perturbation, viral gene transfer, genetically encoded indicators, high-resolution fluorescence microscopy, electron microscopy, 3D analyses, quantitative fluorescence imaging, electrophysiology and behavior.
His current projects are related to (1) the molecular structure and function of central nerve terminals (to explore protein function in the context of synaptic vesicle translocation to, and priming at, the active zones of synaptic terminals), (2) neuronal chloride signaling imaged with a genetically encoded indicator (to study the spatial and temporal distribution of Cl- in hippocampal neurons and the impact of Cl- gradients and local accumulation on GABAergic synaptic transmission), and (3) neuronal mechanisms of odor discrimination (to investigate lateral inhibition mechanism in the olfactory system).