Human 8-to 10-Hz pulsatile motor output during active exploration of textured surfaces reflects the textures' frictional properties

• Active sensing in biological system consists of emitting/receiving a periodic signal to explore the environment. The signal can be emitted toward distant objects. as in echolocation, or in direct contact with the object. for example, whisking in rodents. We explored the hypothesis that a similar mechanism exists in humans. Humans generate periodic signals at similar to 10 Hz during voluntary finger movements, which reflects a pulsatile motor command in the central nervous system. In the present study, we tested whether the similar to 10-Hz signal persists during the active exploration of textures and whether the textures' features can modulate the signal. Our results confirm our assumptions. The similar to 10-Ilz signal persisted during active touch, and its amplitude increased with textures of higher friction. These findings support the idea that the similar to 10-Hz periodic signal generated during voluntary finger movements is part of an active sensing mechanism acting in a pulse-amplitude modulation fashion to convey relevant tactile information to the brain. NEW & NOTEWORTHY For the first time, we show that pulsatile motor output during voluntary movement of a finger persists during active exploration of a surface. We propose that this is part of an active sensing system in humans, with generation of an similar to 10-Hz signal during active touch that reinforces extraction of information about features of the touched surface.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Fysiologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Physiology (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Neurovetenskaper (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Neurosciences (hsv//eng)

Keyword

movement discontinuities

muscle vibrations

pulsatile motor output

tremor

ballistic movement

discharge patterns

muscle activation

finger

movements

40 hz

tremor

slow

contraction

instability

frequency

Neurosciences & Neurology

Physiology

Publication and Content Type

ref (subject category)

art (subject category)