In Vivo Neurophysiology
We study how individual cortical neurons encode sensory stimuli and how sensory representation is affected by behavior. The rodent barrel cortex is an excellent system to study these questions since the individual sensory organs (facial whiskers) are represented by easily identifiable cortical columns. Additionally, our group is part of an international effort to understand human brain function at (sub)cellular resolution.
Sensory processing during behavioral paradigms
During animal behavior, there is a constant interplay between brain areas involved in sensory processing, decision making and motor output. The whisker system is an obvious example of a sensorimotor system where motor output (movement of the sensory organs (i.e. the whiskers)) has to be integrated with incoming sensory information. In turn, the sensorimotor information guides cognitive behaviour. Our research question focusses on the organisational principles of the cortical microcircuit across distinct areas of the sensorimotor system. Techniques used are behavioral training, (in vivo) electrophysiology in awake, behaving animals and post-hoc 3D Neurolucida reconstructions.
Sensory processing in prefrontal cortex
Sensory information can induce shifts in attention and guide decision making and this cognitive behavior critically depends on prefrontal cortex. In this project we study how cognitive behaviour is represented in the prefrontal cortical microcircuit. Techniques used are behavioural training (sensory based decision making), (in vivo) single- and multi-unit electrophysiology in behaving animals and post-hoc 3D Neurolucida reconstructions.
3D reconstruction of labeled neurons
Computer models can be helpful tools to design and direct future experiments and predict possible outcomes. Using 3D reconstructions from in vivo recordings, the first goal is to anatomically reconstruct the cortical column. Then, physiological data will be used to model (and playback) the electrical activity of the cortical column. This project is a collaboration with Marcel Oberlaender and Bert Sakmann from the Max-Planck Institute of Neurobiology, Germany. Techniques used are 3D Neurolucida reconstructions and computer modeling of morphological and physiological properties.
Structure-function relationship of individual neurons in human cortex
Extremely little is known about the morphological and physiological properties of adult human neurons. Together with the labs of Huibert Mansvelder, Idan Segev and Henry Markram, our lab is investigating the relationship between structure and function of individual neurons across all layers in adult human cortex, obtained during resection surgery in the VU medical center (Amsterdam, the Netherlands).
We developed a novel pipeline to handle living brain tissue and preserve resected human brain material for the study of fundamental neurophysiological properties such as passive and active membrane properties, synaptic transmission, spike-timing-dependent (associative) plasticity and action potential back propagation.
Berg*, J., Sorensen*, S., ….. , Segev, I., de Kock, C.P.J., Mansvelder, H.D., Tamas, G., Zeng, H., Koch, C., Lein, E.S., Human neocortical expansion involves glutamatergic neuron diversification. Nature. 2021 Oct;598(7879):151-158. doi: 10.1038/s41586-021-03813-8. Epub 2021 Oct 6.
Douw, L. Nissen, I.A., Fitzsimmons, S.M.D.D., Santos, F.A.N., Hillebrand, A., van Straaten, E.C.W., Stam, C.J., De Witt Hamer, P.C., Baayen, J.C., Klein, M., Reijneveld, J.C., Heyer, D.B., Verhoog, M.B., Wilbers, R., Hunt, S., Mansvelder, H.D., Geurts, J.J.G., de Kock, C.P.J.*, Goriounova, N.A.* Cellular substrates of functional network integration and memory in temporal lobe epilepsy. CerebCtx, 2021 Sep 25; bhab349. doi: 10.1093/cercor/bhab349.
de Kock, C.P.J., Pie, J., Pieneman, A.W., Mease, R.A., Bast, A., Guest, J.M., Oberlaender, M., Mansvelder, H.D., Sakmann, B., High-frequency burst spiking in layer 5 thick-tufted pyramids of rat primary somatosensory cortex encodes exploratory touch. Comms Biol 2021 4:709. doi: 10.1038/s42003-021-02241-8
Yuste*, R., Hawrylycz*, M., …. de Kock, C.P.J., …., Zeng#, H., Lein#, E.S., A community-based transcriptomics classification and nomenclature of neocortical cell types Nat Neurosci 2020 Dec;23(12):1456-1468. doi: 10.1038/s41593-020-0685-8.
Egger, R., Narayanan, R.T., Guest, J.M., Bast, A., Udvary, D., Messore, L.F., Das, S., de Kock, C.P.J., Oberlaender, M., Cortical output is gated by horizontally projecting neurons 1 in the deep layers. Neuron 2020 Jan 8;105(1):122-137.e8. doi: 10.1016/j.neuron.2019.10.011. Epub 2019 Nov 26.
March 2022 (standing, from left to right): René Wilbers, Jean Pie, Tamara Versluis, Eline Mertens, Amber van Mierlo, Christiaan de Kock, Kimlyll Toelen, Femke Waleboer. Front row: Julia Meijer, Patrik Pollack.