Pain captures our attention instantaneously, and makes it hard to pay attention to anything else. But is it possible to direct attention to pain voluntarily and in a specific manner? Which brain mechanisms would drive voluntary direction of attention to pain? Why is this important?
It is likely that chronic pain patients have exaggerated attentional mechanisms (at least those that serve attention to pain) that keep circuits implicated in chronic pain alive and functioning long after the noxious trigger is gone or diminished. On the other hand, studies indicate that attention paid in a particular way may diminish pain: for example, when subjects are told to separately rate two painful stimuli delivered simultaneously (but at different locations), perceived pain decreases. Also, training in tactile discrimination, where one has to focus attention on the location of applied stimuli, results in pain reductions in patients with complex regional pain syndrome.
We decided to identify the brain mechanisms involved in voluntary direction of attention to pain. To do this, we cued healthy volunteers to pay attention to pain location or to pain intensity, and we scanned their brain with functional magnetic resonance imaging before and during painful stimulations.
Interestingly, a set of frontoparietal brain areas (specifically, frontal eye fields and posterior parietal cortex) that mediate attention in other sensory modalities – visual, auditory, somatosensory – mediated attention to pain as well. In addition, attention to location produced greater activity in one particular brain area, called the intraparietal sulcus. Importantly, this area is one of the brain regions that is heavily involved in spatial processing.
Another interesting finding was that the primary somatosensory cortex became activated before the experience of pain. The primary somatosensory cortex is one of the first cortical areas that receives pain-related information. However, classically, pain (or nonpainful somatosensory stimulation) has to be actually present for this area to light up. Thus its activation AFTER subjects learned that pain is coming but BEFORE they ever experienced it, points to the mechanisms by which attention tunes sensory pain processing.
In the future one would hope that by selective stimulation of areas responsible for attention to pain, we could encourage productive forms of attention (for example, attention to location), and discourage counterproductive ones (attention to intensity), to find another weapon in the battle with chronic pain.
About Oleg Lobanov
Dr. Oleg V. Lobanov did his PhD work in the Laboratory of Pain and Cognition under the guidance and supervision of Dr. Robert C. Coghill. Oleg is in his final year of MD/PhD program at Wake Forest School of Medicine, and is applying for residency programs in Child Neurology.
Oleg’s research interests include higher cognitive brain functions (attention, expectation) in pain, their brain mechanisms and their influence on experience of pain. He hopes to find another angle in chronic pain treatment through manipulations of attention and expectation.
Lobanov OV, Quevedo AS, Hadsel MS, Kraft RA, & Coghill RC (2013). Frontoparietal mechanisms supporting attention to location and intensity of painful stimuli. Pain, 154 (9), 1758-68 PMID: 23711484