However, such post-synaptic effects are short-lived, so this explanation would require that CVS produces prolonged firing in vestibular afferents, and thus prolonged excitatory or inhibitory influence on bimodal neurons, throughout the time course of our experiment. An alternative explanation would involve a longer-lasting effect of the transient stimulation of vestibular peripheral organs on the cortical
targets of somatosensory pathways. Such enduring interactions are suggested by the lack of reduction of the modulatory effect observed across our five blocks of testing. CVS might perhaps produce long-lasting modulation of somatosensory synaptic strength by long term potentiation (LTP) of tactile pathways, and long term depression (LTD) of pain pathways. Further research is necessary to investigate these possible mechanisms of vestibular-somatosensory Cobimetinib concentration interaction. What could be the adaptive function of these vestibular modulations
of touch and pain? CVS is a very unnatural stimulus, so we can only speculate on this point. Outside the laboratory, vestibular canal input normally occurs during head rotation, as when an animal re-orients towards a new part of the external environment (Klam and Graf, 2006). We suggest that such reorienting may involve a rebalancing of sensory processing to provide an appropriate Pifithrin-�� in vitro new balance of inputs. For example, pickup of information from novel environments may become urgently important following reorienting (Fecteau et al., 2004). Thus, vestibular signalling of head rotation during orienting movements could trigger increased sensitivity to tactile stimuli. Interestingly,
our data suggest that vestibular input causes a complementary tweaking of the sensitivity of the two main submodalities of somatosensation, buy C59 rather than a general reduction or increase in sensitivity of them. Interestingly, the observation that vestibular input has an analgesic effect is reminiscent of the notion that novel environments are themselves mildly analgesic (Siegfried et al., 1987). The observed tweaking of the sensitivity of the two somatosensory submodalities may reflect a multisensory mechanism for adjusting sensory processing following reorientation to novel environments, thus ensuring efficient perception and motivating exploratory behaviour (Cohen et al., 2007). This work was supported by EU FP7 project VERE and by a Leverhulme Trust Major Research Fellowship to P.H., E.R.F. was supported by a PhD program of the University of Pavia, and by a BIAL Foundation Bursary (215/10) awarded to PH. G.B was supported by PRIN 2007. G.D.I. is University Research Fellow of The Royal Society and is supported by the BBSRC and El.En. “
“Luigi A. Vignolo, M.D. passed away peacefully at home, surrounded by his family, on December 21st, 2011.