Precision rodent whisker stimulator with integrated servo-locked control and displacement measurement

Abstract

We developed a high speed voice coil based whisker stimulator that delivers precise deflections of a single whisker or group of whiskers in a repeatable manner. The device is miniature, quiet, and inexpensive to build. Multiple stimulators fit together for independent stimulation of four or more whiskers. The system can be used with animals under anesthesia as well as awake animals with head-restraint, and does not require trimming the whiskers. The system can deliver 1–2 mm deflections in 2 ms resulting in velocities up to 900 mm/s to attain a wide range of evoked responses. Since auditory artifacts can influence behavioral studies using whisker stimulation, we tested potential effects of auditory noise by recording somatosensory evoked potentials (SEP) with varying auditory click levels, and with/without 80 dBa background white noise. We found that auditory clicks as low as 40 dBa significantly influence the SEP. With background white noise, auditory clicks as low as 50 dBa were still detected in components of the SEP. For behavioral studies where animals must learn to respond to whisker stimulation, these sounds must be minimized. Together, the stimulator and data system can be used for psychometric vigilance tasks, mapping of the barrel cortex and other electrophysiological paradigms.

Spiral laser scanning photoacoustic microscopy for functional brain imaging in rats

“…9(b)–9(e). By stimulating the rat’s whiskers, we anticipated a functional change in the somatosensory cortex 69 (because of the light illumination used in PAI, the visual cortex may have been stimulated as well). Because left nose whiskers were stimulated and nerves cross upon entering the brain (decussation), we expected to see functional changes in the right side of the rat’s brain.…”

A novel vibrotactile system for stimulating the glabrous skin of awake freely behaving rats during operant conditioning

“…Rodents can be trained for behavioral tasks based on sensory inputs from different modalities, such as olfaction (Rajan et al, 2006), vision (Horner et al, 2013), hearing (Talwar and Gerstein, 1999) and touch (Adibi and Arabzadeh, 2011;Harris et al, 1999;Tahon et al, 2011;Walker et al, 2011;Wiest et al, 2010). They can also be conditioned by electrical microstimulation in the cortex (Xu et al, 2004) and drug self-administration (Ikemoto and Sharpe, 2001).…”

“…Moreover, the sinus hair follicle includes striated muscle fibers which enable voluntary movement. Due to the highly magnified cortical representation in rats, the mechanoreceptive fibers and the associated pathways for the vibrissae have been extensively studied in the literature (Adibi and Arabzadeh, 2011;Diamond et al, 2008;Harris et al, 1999;Prigg et al, 2002;Tahon et al, 2011;Walker et al, 2011;Wiest et al, 2010). Additionally, because the afferent and efferent innervation form a closed loop of the sensorimotor pathways, rat vibrissal system is an ideal model for studying active touch (Ahissar, 2008;Kleinfeld et al, 2006).…”