Almost all mammals use their mystacial vibrissae (whiskers) as important tactile sensors. There are no sensors along the length of a whisker: all sensing is performed by mechanoreceptors at the whisker base. To use artificial whiskers as a sensing tool in robotics, it is essential to be able to determine the three-dimensional (3D) location at which a whisker has made contact with an object. Wit...

This study addresses the origins of multi-whisker receptive fields of neurons in the thalamic ventral posterior medial (VPM) nucleus of the rat. We sought to determine whether multi-whisker receptive field synthesis occurs in VPM through convergent projections from the principalis (PrV) and interpolaris (SpVi) nuclei, or in PrV via intersubnuclear projections from the spinal trigeminal complex....

BACKGROUND AND PURPOSE Using a rodent model of ischemia (permanent middle cerebral artery occlusion), our laboratory previously demonstrated that 4.27 minutes of patterned single-whisker stimulation delivered over 120 minutes can fully protect from impending damage when initiated within 2 hours of permanent middle cerebral artery occlusion ("early"). When initiated 3 hours postpermanent middle ...

N-methyl-d-aspartate receptor (NMDAR)-mediated activity is required for whisker-related neural patterning in the rodent brain. Deletion of the essential NMDAR subunit NR1 gene in excitatory cortical neurons prevents whisker-specific barrel formation and impairs thalamocortical afferent patterning. We used electrophysiological and voltage-sensitive dye imaging methods to assess synaptic and sens...

Roughly 20 years ago Valentino Braitenberg published a book on vehicles—a treatment of the amazingly complex behavior of a variety of very simple machines (Braitenberg 1984). This approach was inspired by the “law of uphill analysis and downhill invention.” Accordingly it is easier to design a mechanism to do something from scratch than to figure out just how nature has contrived to do it. Alth...

previous studies have shown that the receptive field properties, spontaneous activity and spatio-temporal interactions of low-threshold mechanical somatosensory cells in the barrel cortex are influenced by c-fibers. in this study, we examined the effect of c-fiber depletion on response properties of barrel cortex neurons following experience dependent plasticity. methods: in this study, exterac...

The isomorphic representation of the contralateral whisker pad in the rodent cerebral cortex has served as a canonical example in primary somatosensory areas that the contralateral body surface is spatially represented as a topographic map. By characterizing responses evoked by multiwhisker stimuli, we provide direct evidence that the whisker region of the rat primary somatosensory cortex (SI) ...

The role of inhibition in sensory cortical map plasticity is not well understood. Here we tested whether inhibition contributes to expression of receptive field plasticity in developing rat somatosensory (S1) cortex. In normal rats, microiontophoresis of gabazine (SR 95531), a competitive gamma-aminobutyric acid (GABA)-A receptor antagonist, preferentially disinhibited surround whisker response...

The somatosensory barrel cortex in rodents contains a topographic map of the facial whiskers where each cortical barrel is tuned to a corresponding whisker. However, exactly when this correspondence is established during development and how precise the functional topography of the whisker protomap is at birth, before the anatomical formation of barrels, are questions that remain unresolved. Her...

Rodent whisking is an exploratory behavior that can be modified by sensory feedback. Consistent with this, many whisker-sensitive cortical regions project to agranular motor [motor cortex (MI)] cortex, but the relative topography of these afferent projections has not been established. Intracortical microstimulation (ICMS) evokes whisker movements that are used to map the functional organization...