Rodents explore the world by palpating objects with their whiskers. Whiskers interact with objects, causing stresses in whisker follicles and spikes in sensory neurons, which are interpreted by the brain to produce tactile perception. The mechanics of the whisker thus couple self-movement and the structure of the world to sensation. Whiskers are elastic thin rods; hence, they tend to vibrate. W...

Recent advances in functional imaging and neuronal recording techniques demonstrate that the spatial spread and amplitude of whisker functional representation in the somatosensory cortex of the adult rodent is extensive, but subject to modulations. One of the strongest modulators is naturalistic whisker use. In the cortices of rodents that have been transferred from their home cage to live for ...

Tungsten powder mixed with an appropriate amount of nickel and iron powders is used as raw material to fabricate large-scale tungsten whisker-like structure. The morphology, microstructure and composition of the whisker-like tungsten are observed and tested by scanning electron microscope and FESEM, transmission electron microscopy, X-ray spectroscopy, and X-ray diffraction, respectively. The m...

Tactile information available to the rat vibrissal system begins as external forces that cause whisker deformations, which in turn excite mechanoreceptors in the follicle. Despite the fundamental mechanical origin of tactile information, primary sensory neurons in the trigeminal ganglion (Vg) have often been described as encoding the kinematics (geometry) of object contact. Here we aimed to det...

The role of facial vibrissae (whiskers) in the behavior of terrestrial mammals is principally as a supplement or substitute for short-distance vision. Each whisker in the array functions as a mechanical transducer, conveying forces applied along the shaft to mechanoreceptors in the follicle at the whisker base. Subsequent processing of mechanoreceptor output in the trigeminal nucleus and somato...

Knutsen, Per Magne, Dori Derdikman, and Ehud Ahissar. Tracking whisker and head movements in unrestrained behaving rodents. J Neurophysiol 93: 2294–2301, 2005. First published November 24, 2004; doi:10.1152/jn.00718.2004. Due to recent advances that enable real-time electrophysiological recordings in brains of awake behaving rodents, effective methods for analyzing the large amount of behaviora...

1. Extracellular single-unit recordings and controlled whisker stimuli were used to compare response properties of cells in the barreloids of the ventral posterior medial nucleus of the thalamus and the barrels in the rat primary somatosensory cortex. Whiskers were deflected alone or in combinations involving up to four immediately adjacent whiskers to assess their relative inhibitory and excit...

The need to better understand whisker growth has dramatically increased as component suppliers convert from tin-lead (SnPb) finishes to Pb-free finishes of Sn and low-alloy-content Sn-based finishes. Whiskers are spontaneous growth of metal filaments emanating from the finish surface. The issues with whiskers are they may grow long enough to cause short circuiting or break off and interfere wit...

Layer 5 (L5) pyramidal neurones constitute a major sub- and intracortical output of the somatosensory cortex. This layer 5 is segregated into layers 5A and 5B which receive and distribute relatively independent afferent and efferent pathways. We performed in vivo whole-cell recordings from L5 neurones of the somatosensory (barrel) cortex of urethane-anaesthetized rats (aged 27-31 days). By deli...

Characterization of neurovascular relationships is critical to accurate interpretation of functional neuroimaging data. We have previously observed spatial uncoupling of optical intrinsic signal imaging (OIS) and evoked potential (EP) responses in rodent barrel cortex following simultaneous whisker and forelimb stimulation, leading to changes in OIS response magnitude. To further test the hypot...