Figure 1 - uploaded by Johannes Mayrhofer
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Brain, neocortex and microcircuits. (A) Anatomical subdivision of the mammalian brain (sagittal section through the human brain, taken from (Drake, 2010)): medulla, pons, cerebellum, midbrain, diencephalon (thalamus and hypothalamus), and cerebral hemispheres (or telencephalon: cerebral cortex, basal ganglia, the amygdala, and the hippocampal formation and corpus callosum). (B) A series of mammalian brains (taken from (Roth and Dicke, 2005)). Humans do not have the largest brain in absolute terms and are exceeded in size by many cetaceans (whales, dolphins, porpoises and the elephants). They also do not have the most convoluted cortex. (C) The neurons of the cerebral cortex are organized in characteristic layers (adapted from (Kandel, 2000)). Left subpanel: The Golgi stain shows neuronal cell bodies and dendritic trees. The Nissl method displays cell bodies and proximal dendrites. A Weigert stain for myelinated fibers reveals the pattern of axonal distribution. Right subpanel: Different types of GABA-ergic neurons (dark gray) and putative GABA-ergic neurons (light gray) have different connections with pyramidal (P) and spiny non-pyramidal (SNP) cells in the neocortex. The GABA-ergic cells include chandelier cells (C), which terminate exclusively on the axons of other neurons, and the large and small basket cells (LB, SB), whose axons terminate mainly on other cell bodies. Double bouquet (DB) and neurogliaform cells (NG) may also be GABA-ergic. (D) Representation of the major connections in the canonical microcircuit (adapted from (da Costa and Martin, 2010)). Excitatory connections are represented by arrows and inhibitory ones as lines with round ends. Neurons from different cortical layers or brain structures are represented as circles. "Lx" labels the cortical layer where the cell body is located, "Thal" labels the thalamus and "Sub" labels other subcortical structures.
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... In line with experimental investigations, theoretical models of somatosensory function and algorithmic computation are crucial for understanding brain function (Bernardi et al., 2021;Brecht, 2017;Maravall and Diamond, 2014;Marr, 1982). Indeed theoretical and experimental neuroscience benefit greatly from cooperation, and together will play an integral role in finally cracking the somatosensory neural code (Panzeri et al., 2017 (Mayrhofer, 2013;O'Connor et al., 2010), visual (Burgess et al., 2017), auditory (Sanders and Kepecs, 2012), olfactory (Abraham et al., 2012;Resulaj and Rinberg, 2015) and even gustatory (Vincis et al., 2020) modalities. In many of these studies it is advantageous to restrict movement through head-fixation, which allows for controlled stimulus presentation, quantification of motor output and stability for sensitive neurophysiological recordings (Guo et al., 2014c). ...
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