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- Ackerley, Rochelle, 1980, et al.
(författare)
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The touch landscape
- 2016
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Ingår i: Affective Touch and the Neurophysiology of CT Afferents. Olausson H., Wessberg J., Morrison I., McGlone F. (eds.). - New York, NY : Springer. - 9781493964185 ; , s. 85-109
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Somatic sensation comprises four main modalities relaying tactile, thermal, painful, or pruritic (itch) information to the central nervous system. These input channels can be further classified as sub-serving sensory functions, such as spatial and temporal discrimination, and the provision of essential information for controlling and guiding exploratory manual behaviours, or affective functions that include the provision of the subjective experience of affective or emotional pleasurable touch. Signalling in fast-conducting myelinated peripheral nerve fibres (Aβ afferents) is important for the discriminative properties of tactile sensations, whereas signalling in unmyelinated peripheral nerve fibres, C-tactile (CT) afferents seems to be important for the rewarding, emotional properties of touch. CT afferents have specific biophysical, electrophysiological, neurobiological and anatomical properties to drive the temporally delayed affective somatic system. This chapter explores step by step the differences between the discriminative and affective touch systems, from the first stage of encoding touch in the skin to the neural pathways in the brain. The below quote from Bentley (Am J Psychol 11:405-425, 1900) reiterates the complexity of the skin and the wonder in the phenomenon of somatosensation: ‘The skin is burdened with offices. One of the surprises of physiology is the revelation of the multitude of functions performed by this apparently simple organ. As a rind it is not only the container, but the warder-off, and also the go-between for the organism and its world; tegument, buckler, interagent. It is small wonder that its work is represented in mental process; that many of our most worn and useful perceptions are made up of cutaneous sensations.'. © 2016 Springer Science+Business Media New York.
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| 2. |
- Björnsdotter, Malin
(författare)
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Brain Processing of CT-Targeted Stimulation
- 2016
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Ingår i: Affective Touch and the Neurophysiology of CT Afferents. Olausson, H., Wessberg, J., Morrison, I., McGlone, F. (Eds.). - New York, NY : Springer. - 9781493964185 ; , s. 187-194
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Bokkapitel (refereegranskat)
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| 3. |
- Cole, J., et al.
(författare)
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Insights from A-beta or C-fibre denervated subjects
- 2016
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Ingår i: Affective Touch and the Neurophysiology of CT Afferents. Olausson H., Wessberg J., Morrison I., McGlone F. (eds.). - New York, NY : Springer. - 9781493964185 ; , s. 175-185
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- CT afferents have been known for years, since 1939 when Zotterman suggested they might contribute to itch. But their study has been hampered because any low threshold tactile stimulus will also activate large numbers of Aβ afferents. To investigate the psychophysics of CT afferents has recently become possible through microneurography, allowing selective recording from groups of these nerves, (Löken et al., Nat Neurosci 12(5):547-548, 2009 and this volume), and through the study of two rare cohorts of people who have lost either large fibre afferents due to disease or have selective loss of C afferents themselves due to hereditary neuropathy. This chapter details this latter work, and though comparisons between those with neurological conditions and control subjects must always be done with caution, such work can allow some insights into the normal functioning of the CT system. Slow stroking on the hairy skin of deafferented subjects is poorly localised, but described, during forced choice experiments, as pleasant, and leads to activations in insula cortex but not sensory cortex. Since Ct activation is perceived poorly, if at all in deafferented subjects this suggests that a role for CT afferents may be to-in some way-set, or prime, information through Aβ pathways with affective valence. © 2016 Springer Science+Business Media New York.
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| 4. |
- Liljencrantz, J., et al.
(författare)
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Pain and touch: Roles for c-tactile afferents in pain inhibition and tactile allodynia
- 2016
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Ingår i: Affective Touch and the Neurophysiology of CT Afferents. Olausson H., Wessberg J., Morrison I., McGlone F. (eds.). - New York : Springer. - 9781493964185 ; , s. 409-420
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- In humans there is a positive correlation between the pleasantness perception of soft skin stroking and the firing rate of unmyelinated C-low-threshold mechanoreceptive afferents (often abbreviated C-LTMR in animals and C-tactile and CT afferents in humans). CT-targeted touch reduces heat pain in humans suggesting that activation of the CT system modulates pain perception. This finding is supported by animal work which has shown that C-LTMRs inhibit nociceptive signaling at the spinal cord level, release a protein (TAFA4) with analgesic effects, and have positively reinforcing and anxiolytic behavioral effects. However, under pathophysiological conditions, research in mice and humans instead suggests a role for CLTMRs and CTs in tactile allodynia. There is a divergence in results with some studies pointing to CLTMRs/CTs driving tactile allodynia, whereas others suggest a modulatory role. © 2016 Springer Science+Business Media New York.
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| 5. |
- McGlone, F., et al.
(författare)
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Affective touch and human grooming behaviours: Feeling good and looking good
- 2016
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Ingår i: Affective Touch and the Neurophysiology of CT Afferents. Olausson H., Wessberg J., Morrison I., McGlone F. (eds.). - New York : Springer. - 9781493964185 ; , s. 265-282
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Grooming behaviours, whether directed at the self or at others, are ubiquitous within the animal kingdom-from bees to bonobos. Having evolved for hygienic purposes, it is in primates that grooming behaviours supersede their original role to one in which there is a clear social element: nurture, control of dominance relationships, facilitating group cohesion, etc. In humans, grooming has been seen traditionally as providing a functional, plus an aesthetic, benefit-we keep clean and we look good. However, there may be another factor driving these impulses to groom ourselves: one which is less overt and a consequence of grooming that actually makes us feel good as well. It is axiomatic that grooming involves touching and, as the previous chapters in this book have described, there exists in the skin of the body a population of unmyelinated mechanosensory nerves that respond optimally to precisely the kinds of touch that typify many grooming behaviours-gentle moving touch. © 2016 Springer Science+Business Media New York.
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| 6. |
- Norrsell, Ulf, 1937
(författare)
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Some historical aspects of cutaneous psychophysics
- 2016
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Ingår i: Affective Touch and the Neurophysiology of CT Afferents. Olausson H., Wessberg J., Morrison I., McGlone F. (eds.). - New York : Springer. - 9781493964185 ; , s. 111-128
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The subject called psychophysics reflects an ambition to explore the mostly human characteristics of neurophysiology for both theoretical and medical purposes. It may be traced from the first half of the nineteenth century, starting with advocates like Johannes Müller and Ernst Weber. The historical development of the issue’s cutaneous subdivision may be followed through publications of a restricted series of findings. Their authors as well as their messages are still recalled in many instances. The development followed the creation of new techniques. Nevertheless, it was not always the case. Some important observations were overlooked in the beginning and thus some possible developmental strategies were delayed for decades. © 2016 Springer Science+Business Media New York.
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