As the result of the global movement to lead-free electronics, companies which assemble semiconductor devices are switching from finishes incorporating lead to pure tin or high tin lead-free alloys. This transition has resulted in a reliability issue, concerning the formation of conductive tin whiskers which can grow across leads of a package and cause current leakage or short circuits. This pa...

In an attempt to understand how the brain encodes tactile stimuli, neuroscientists commonly investigate how rodents translate whisker motion into a sensory percept. Analysis of whisker dynamics is a challenging task. Rats, have about 30 whiskers per side and in single-viewing angle experiments, occlusion and intersection occur frequently. In this paper we present an unsupervised method for whis...

The tactile somatosensory pathway from whisker to cortex in rodents provides a well-defined system for exploring the link between molecular mechanisms, synaptic circuits, and behavior. The primary somatosensory cortex has an exquisite somatotopic map where each individual whisker is represented in a discrete anatomical unit, the "barrel," allowing precise delineation of functional organization,...

− Many studies address how neurons in the barrel cortex of rats react to stimulation of the rat’s whiskers. In this study we analyse how the statistical properties of whisker deflections from typical surfaces relate to the properties of neurons in the somatosensory system. We built an artificial whisker system to record realistic natural tactile data. An artificial whisker is moved about a set ...

We have extended the previous model [1,2] of experience-dependent plasticity in the rat cortical representation of the whiskers (the barrel cortex) to include excitatory and inhibitory interactions within a barrel-column. Recent experimental observations [3] indicate that after trimming all but one whisker on one side of the rat snout, the spared and deprived whisker dominance distribution was ...

The murine vibrissae sensorimotor system has been scrutinized as a target of motor learning through trace classical conditioning. Conditioned eyelid responses were acquired by using weak electrical whisker-pad stimulation as conditioned stimulus (CS) and strong electrical periorbital stimulation as unconditioned stimulus (US). In addition, conditioned vibrissal protraction was obtained pairing ...

In whiskered animals, activity is evoked in the primary sensory afferent cells (trigeminal nerve) by mechanical stimulation of the whiskers. In some cell populations this activity is correlated well with continuous stimulus parameters such as whisker deflection magnitude, but in others it is observed to represent events such as whisker-stimulator contact or detachment. The transduction process ...

Rodent whisker input consists of dense microvibration sequences that are often temporally integrated for perceptual discrimination. Whether primary somatosensory cortex (S1) participates in temporal integration is unknown. We trained rats to discriminate whisker impulse sequences that varied in single-impulse kinematics (5-20-ms time scale) and mean speed (150-ms time scale). Rats appeared to u...

Spike timing-dependent plasticity (STDP) is a computationally powerful form of plasticity in which synapses are strengthened or weakened according to the temporal order and precise millisecond-scale delay between presynaptic and postsynaptic spiking activity. STDP is readily observed in vitro, but evidence for STDP in vivo is scarce. Here, we studied spike timing-dependent synaptic depression i...

The current view of whisker movement is that approximately 25 whiskers on each side of the face move in synchrony. To determine whether whiskers are constrained to move together, we trained rats to use two whiskers on the same side of the face in simple behavioral tasks and videotaped the whiskers during the task. Here we report that the movement of adjacent whiskers is usually synchronous but ...