Keywords: neurodevelopment, neuronal communication, oscillations, neuronal architectures, multisensory integration, behavioral states, attention.
The concept of Multisensory Integration (MSI) refers to the brain's ability to generate a unified perceptual representation from a myriad of incoming sensory signals from the outside world. MSI mechanisms are essential in the construction of outside world representations and are thought to play a crucial role in higher cognitive functions, such as memory, attention, and consciousness. In cortical microcircuits, MSI mechanisms encompass complex relationships between unicellular, ensembles, and mass-action responses that allow sensory integration, sensory discrimination, and perceptual inferences among different sensory channels.
This new framework is being actively investigated in our lab. We want to understand how MSI arise during neurodevelopment, and what are the mechanisms involved in the generation of this unitary percepts.
How do mammals develop multimodal processing capabilities?
One might imagine two extreme scenarios able to explain the emergence of MSI capabilities during development. On the one hand, the statistical regularities imposed by the environment might determine, through evolution and natural selection, the emergence of specific MSI mechanisms. As such, MSI capabilities might be the result of genetically determined interactions. On the other hand, developing mammals undergo an extended period of experience-dependent development, which would enable the acquisition of sufficient sensory experience before adulthood. Multisensory regularities might raise during postnatal brain development through the accumulation of sensory experience. Which of these two scenarios might explain the emergence of MSI capabilities? How does MSI arise during early postnatal development? Does MSI arise from early experience or intrinsic brain wiring? What are the developmental mechanisms that have a direct influence on the expression of MSI? Under these general questions, we attempt to address the role of early experience during neurodevelopment.
How do different organizational brain levels (from single cells to neuronal populations) interact to generate a subjectively unitary multisensory percept?
Usually, we study sensory perception focusing on one modality at a time. However, our behavior is much more driven by the integration of information obtained through multiple sensory sources. For example, when we eat a piece of chocolate, we see, feel, smell, and taste the chocolate at the same time. We experience these multiple sensations as an integrated perceptual whole. How is our brain able to effortlessly integrate these different sensory modalities? What are the neuronal mechanisms underlying multisensory integration?
Multisensory integration can be subserved by coordinated oscillatory responses through different brain regions. By using state-of-the-art analytical tools, we aim to characterize these coordinated dynamics.
We want to determine whether modifications of the oscillatory activity of sensory cortical networks can coordinate and amplify neuronal responses during multisensory integration through neuronal entrainment to rhythmic oscillations.
Our lab is part of the Cognitive and Systems Neuroscience Group (CSN). We contribute to the understanding of the role of neuronal oscillations during multimodal processing and perception. Our lab specializes in high-density laminar recordings and techniques to study the coordination between neuronal circuits and mass-neuronal recording signals during development. In this context, we use the ferret as a model of cognitive neurodevelopment. Also, together with professor Pennartz and our colleagues at UMC, we study EEG oscillatory markers of neurological deficits. Other active collaborations are with Dr Umberto Olcese (FLAG-ERA projects CANON and DOMINO) and Dr Jorge Mejías (computational models of hierarchical oscillations).
I am the coordinator of the Master track “Cognitive Neurobiology and Clinical Neurophysiology (CN2)”. CN2 is part of the Neurobiology tracks of the Master in Biomedical Sciences. We focus on the challenge to connect different levels at which we can study brain functions: from single neurons, via circuits and networks, to behavior and cognition. Within this master’s track, I teach in different courses a wide range of contents, from basic neuronal neurophysiology to advanced analytical techniques of brain connectivity. I also teach and coordinate the “MATLAB Applied to Neuronal Data” (MAND) course. Here, we give the students an overview of the advanced analytical techniques currently used in cognitive neuroscience and their implementation in MATLAB.
Starting in 2021, I will co-coordinate the course “The Integrated Brain” (TIB) in collaboration with Prof. Victor Lamme, from the Psychology Faculty at the UvA. TIB is a third-year Bachelor in Psychobiology course. Here, we aim to integrate the knowledge of the brain function obtained at different levels. From cellular level approach, focused on neuronal physiology and neuronal interactions, to a cognitive and systems neuroscientific view, aiming to understand how the brain implements behavior. Examples of topics are perception, decision-making, and attention.
I coordinate different internship positions offered within the CNS group and their different labs. Our selection process usually starts during October-November of each year to fill in internship positions between January to July. Occasionally, we also offer internship positions for the second semester of the year. If you are interested, please send an email with your CV and motivation to me (email can be found on top of the page).
I am an Assistant Professor at the CSN group within the Swammerdam Institute for Life Sciences since 2011. I received my Medical Doctorate Degree (M.D.) from the University of Chile in 2000 and my Ph.D., under the supervision of Francisco Aboitiz, from the Catholic University of Chile in 2005. During my Ph.D., I studied EEG oscillatory dynamics in Schizophrenia patients.
In 2005, I moved to Nijmegen to work at the Donders Institute for Brain, Behaviour, and Cognition. I focused on the role of long-range neuronal synchronization and visual attention. At the Donders Institute, we developed a 252–channel electrocorticogram (ECoG)–array, which we used to record LFPs responses in several areas simultaneously. Using Granger causality analyses, we demonstrated that gamma synchronization between V1 and V4 is essentially feedforward (bottom-up). Conversely, beta (14—18 Hz) oscillations convey synchronous feedback relationships between brain areas, distributed to the entire visual hierarchy. These contributions helped to understand the mesoscale mechanisms contributing to cognitive functions and perception.
My current research interests are manifold: I aim to understand what the mechanisms underlying long-range neuronal communication and multisensory integration during neurodevelopment are, how neurodevelopment shapes cortical microcircuits and make them suitable to perform cognitive computations, how the cortical column organization supports multimodal integration across different brain areas, and whether such architecture is conserved across species and specialized brain regions.