Somatosensation and body perception: the integration of afferent signals in multisensory cognitive processes
authors
keywords
- Touch
- Tactile
- Body
- Human
- Perception
- Temperature
- Nociception
- Mechanoreception
document type
COUVabstract
Humans have evolved to interact smoothly with their environment and with others. There are highly complex processes that enable these interactions and many systems are engaged, from the peripheral somatosensory system to a distributed network of cortical regions. This chapter will address the pathway from the peripheral receptors to the brain, including steps where there is the potential for the processing and integration of information, as well as why these have occurred in our evolution. We have a vast system of somatosensory afferents that are distributed over our skin and in our bodies to capture precise signals about our interactions with the world. Somatosensory afference comes from mechanical, thermal, and chemical stimuli, where numerous different types of somatosensory afferent, namely those that respond to mechanoreceptive, thermoreceptive, and/or nociceptive signals respectively, register specific contact and behavior. These signals are persistent and there is considerable integration of this information even before it reaches the brain. Once the input reaches sub-cortical structures and is passed on to the cerebral cortex, there is again a wealth of processes that interact smoothly, to produce the awareness of our body in space and its interactions. These include principal somatosensory targets, such as the primary (S1) and secondary (S2) somatosensory cortices, and the insula. In the integration of information, many other regions are involved, including the activation of a range of cognitive (e.g. attention, memory, learning) and emotional/affective mechanisms, as well as multisensory processing. This chapter will consider the intricacies of these processes, by exploring the sensory origin of body perception.
