Peripheral neural correlates of temperature sensations in man

The present paper describes recent advances in our knowledge on human sensations as correlated to neural activity in specific (thermal) and non-specific (mechanothermal) skin afferents. In this respect, considerable progress has been achieved by technical developments of microelectrodes that allow the percutaneous recording of single fiber activity of myelinated and of unmyelinated skin afferents from conscious human subjects. Psychophysical and neurophysiological measurements have been performed to identify possible neural correlates of static and dynamic temperature sensations, heat sensation and paradoxical thermal sensations. The functional role of temperature sensitive mechanoreceptors is discussed. These correlations between thermal sensations and neural events in man may be regarded as first approximations since, at the present time, quantitative neural data are based only on small populations of primary thermal afferents.