Wednesday, october 21, 2009: all rapidly adapting receptors are associated with connective tissue. 6 different touch receptors (therefore touch is a hugely important sensation/stimulus) Some slowly adapting (free nerve ending, merkel"s, ruffini) Can detect vibrations of stimuli (fast adapting receptors) very accurately: free nerve endings part of the sensation of many modalities; different sensation mechanisms between. Touch receptors have axons that conduct signals at about 80m/s; pain receptors (at the fastest) have axons that conduct signals at about 20m/s. May reflect an increased need for tactile sensation in mammals compared with lower-order modalities: touch faster than pain organisms, pain: two types. Slow pain/ache: goes through the c pathway. Fast/sharp pain: goes through alpha-delta pathway: clusters of axons in a nerve: classification by conduction velocity. Alpha conduct signals faster than beta axons; different diameters produce different conduction velocities; larger diameter = faster conduction; all of these fibres are a fibres.