Tactile roughness discrimination of the finger pad relies primarily on vibration sensitive afferents not necessarily located in the hand

摘要: This study aims to investigate the relative contribution of remote mechanoreceptors perception roughness and spatial acuity. We examined two unilateral pathological conditions affecting differently innervation index finger: carpal tunnel syndrome (n=12) surgically repaired complete traumatic median nerve section at wrist following surgical repair (n=4). employed a control condition consisting ring-block anesthesia entire in 10 healthy subjects model denervation fingertip. Spatial acuity ability discern were assessed using grating orientation task discrimination task, respectively. In patients with syndrome, we observed significant reduction resolution but an intact discriminate For there was no recovery up 20 months post surgery progressive full between 6 9 months. Finally, anesthetic ring bloc group, block completely disrupted performances unexpectedly left unaffected task. Taken together, these lines evidence support view that neural mechanisms underlying tactile differ from those involved Vibrotaction is necessary sufficient for fine textures and, when fingerpad compromised, information about can be captured encoded by located more proximal tissues where intact.