Ch7 - Somatosenses

Question 1

Receptors

Answer 1

Merkel’s disk (small, sharp, hairy & glabrous) - form, roughness, especially by fingertips

Ruffini corpuscles (large, diffuse, hairy & glabrous) - static, skin stretching, proprioception

Meissner’s corpuscles (small, sharp, glabrous) - edge contours, especially by fingertips

Pacinian corpuscles (large, diffuse, hairy & glabrous) - vibration, info from end of held elongated object

Question 2

Temperature

Answer 2

Temperature response to warmth (deep) or coolness (beneath epidermis) (mammalian thermal receptors table/graph?)

Question 3

Pain - 3 components

Answer 3

Sensory - pure perception of intensity of painful stimuli (Spinal cord → ventral posterolateral thalamus → primary & secondary somatosensory cortex)

Immediate emotional consequences - unpleasantness (anterior cingulate cortex (decreased by hypnosis) & insular cortex)

Long-term emotional implications of chronic - threat to future comfort well-being (prefrontal cortex - phantom limb)