Giandomenico Iannetti "Dolore e difesa: meccanismi corticali di identificazione dei pericoli ambientali" - 19 Febbraio 2015 ore 13.00

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Prof. Giandomenico Iannetti,   Full Professor of Neuroscience, Department of Neuroscience, Physiology and Pharmacology University College London (UK)

 

"Dolore e difesa: meccanismi corticali di identificazione dei pericoli ambientali"

"Avoiding pain: cortical responses to nociceptive stimuli and defensive movements"

 

Neuroimaging and neurophysiological studies in humans have shown that transient nociceptive stimuli causing pain elicit responses in an extensive network of cortical structures. This network, often referred to as the "pain matrix", has been assumed to be specifically reflecting nociceptive processing, and extensively used in the past 30 years to gain knowledge about the cortical mechanisms underlying nociception and pain perception in humans.

In the first part of this talk I will provide evidence that, in contrast with this dominant view, these brain responses are not specific for the perception of pain. These results indicate that it is incorrect to refer to these responses as originating from a "pain matrix", and question the appropriateness of relying on them to infer that in individual is in pain, or to build models of where and how nociceptive input is processed in the human brain to generate painful percepts.

Instead, I will suggest that the largest part of pain-evoked brain responses are related to detection of environmental threats – they represent a basic mechanism through which the individual detects, reorients attention and reacts to sensory events threatening the integrity of the body, regardless of the sensory channel conveying this information.

In the second part of this talk I will illustrate the rules that the nervous system obeys to identify threatening changes in the sensory environment, and provide evidence that the brain responses elicited by a salient stimuli are sensitive to behaviourally relevant changes in the location of a potential threat with respect to the body.

I will finally show that the brain responses elicited by transient nociceptive stimuli are related to the execution of defensive movements, aimed to protect the body from threats in the sensory environment. Furthermore, by exploring the dependence of such responses on the position of the threatening stimulus in space, I will show evidence supporting the existence of a part of space surrounding the body (a "defensive" peripersonal space, DPPS) representing a safety margin advantageous for survival.

References

Iannetti GD, Salomons TV, Moayedi M, Mouraux A, Davis KD.

Beyond metaphor: contrasting mechanisms of social and physical pain.

Trends in Cognitive Sciences, 2013 Aug; 17(8):371-8.

Liang M, Mouraux A, Hu L, Iannetti GD.

Primary Sensory Cortices Contain Distinguishable Spatial Patterns of Activity for Each Sense.

Nature Communications, 2013; 4:1979. doi: 10.1038/ncomms2979

Mouraux A, Diukova A, Lee MC, Wise RG, Iannetti GD.

A multisensory investigation of the functional significance of the "pain matrix".

NeuroImage 2011; 54:2237-49.

Sambo CF, Forster T, Williams S, Iannetti GD.

To Blink or Not to Blink: Fine Cognitive Tuning of the Defensive Peripersonal Space.

Journal of Neuroscience 2012; 32:12921-7.

Sambo C, Iannetti GD.

Better safe than sorry? The safety margin surrounding the body is increased by anxiety.

Journal of Neuroscience, 2013; 33:14225-30.

Zhang ZG, Hu L, Hung YS, Mouraux A, Iannetti GD.

Gamma-band oscillations in the primary somatosensory cortex--a direct and obligatory correlate of subjective pain intensity.

Journal of Neuroscience 2012; 32(22):7429-38.