A number of cortical regions are involved in processing pain-related information. The SI and SII somatosensory cortices process mainly sensory discriminative attributes but also play an important role in recognition and memory of painful events. Regions such as SII and the posterior insula appear to be the first stations that house processes by which attention profoundly shapes both behavioral responses and subjective pain experience. We investigated the influence of directed attention on pain-induced oscillations and synchronization processes using magnetoencephalogram in combination with an oddball paradigm in 20 healthy subjects. The subject's task was to count rare painful electrical stimuli applied to one finger, while ignoring frequent stimuli at a different finger. A high detection ratio was observed for all blocks and subjects. Early evoked oscillations in the ␦-band increased with higher stimulus intensity and directed attention, most prominently at contralateral sensorimotor sites. Furthermore, suppression and rebound of ␤ activity were observed after painful stimulation. Moreover, induced oscillatory activity in the high ␥-band increased with directed attention, an effect being significantly stronger for high compared with low stimulus intensity. Coupling analysis performed for this high ␥ response revealed stronger functional interactions between ipsilateral and contralateral sites during attention. We conclude that pain-induced high-frequency activity in sensorimotor areas may reflect an attentional augmentation of processing, leading to enhanced saliency of pain-related signals and thus to more efficient processing of this information by downstream cortical centers.

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A number of interspinous process devices have recently been introduced to the lumbar spinal market as an alternative to conventional surgical procedures in the treatment of symptomatic lumbar stenosis.

Attention is an important factor that is able to strongly modulate the experience of pain. In order to differentiate cortical mechanisms underlying subject-driven (i.e., top-down) and stimulus-driven (bottom-up) modes of attentional pain modulation, we recorded electric brain activity in healthy volunteers during painful laser stimulation while spatial attention and stimulus intensity were systematically varied. The subjects’ task was to evaluate the pain intensity at the attended finger, while ignoring laser stimuli delivered to the other finger. Top-down (attention) and bottom up (intensity) influences differed in their effects on oscillatory response components. Attention towards pain induced a decrease in alpha and an increase in gamma band power, localized in the insula. Pain intensity modulated delta, alpha, beta and gamma band power. Source localization revealed stimulus driven modulation in the cingulate gyrus (CG) and somatosensory areas for gamma power changes. Our results indicate that bottom-up and top-down modes of processing exert different effects on pain-induced slow and fast oscillatory activities. Future studies may examine pain-induced oscillations using this paradigm to test for altered attentional pain control in patients with chronic pain.

Modern forms of music therapy are clinically established for various therapeutic or rehabilitative goals, especially in the treatment of chronic pain. However, little is known about the neuronal mechanisms that underlie pain modulation by music. Therefore, we attempted to characterize the effects of music therapy on pain perception by comparing the effects of 2 different therapeutic concepts, referred to as receptive and entrainment methods, on cortical activity recorded by magnetencephalography in combination with laser heat pain. Listening to preferred music within the receptive method yielded a significant reduction of pain ratings associated with a significant power reduction of delta-band activity in the cingulate gyrus, which suggests that participants displaced their focus of attention away from the pain stimulus. On the other hand, listening to self-composed "pain music" and "healing music" within the entrainment method exerted major effects on gamma-band activity in primary and secondary somatosensory cortices. Pain music, in contrast to healing music, increased pain ratings in parallel with an increase in gamma-band activity in somatosensory brain structures. In conclusion, our data suggest that the 2 music therapy approaches operationalized in this study seem to modulate pain perception through at least 2 different mechanisms, involving changes of activity in the delta and gamma bands at different stages of the pain processing system.

Painful events in our environment are often accompanied by stimuli from other sensory modalities. These stimuli may influence the perception and processing of acute pain, in particular when they comprise emotional cues, like facial expressions of people surrounding us. In this whole-head magnetoencephalography (MEG) study, we examined the neuronal mechanisms underlying the influence of emotional (fearful, angry, or happy) compared to neutral facial expressions on the processing of pain in humans. Independent of their valence, subjective pain ratings for intracutaneous inputs were higher when pain stimuli were presented together with emotional facial expressions than when they were presented with a neutral facial expression. Source reconstruction using linear beamforming revealed pain-induced early (70 -270 ms) oscillatory beta-band activity (BBA; 15-25 Hz) and gamma-band activity (GBA; 60 -80 Hz) in the sensorimotor cortex. The presentation of faces with emotional expressions compared to faces with neutral expressions led to a stronger bilateral suppression of the pain-induced BBA, possibly reflecting enhanced response readiness of the sensorimotor system. Moreover, pain-induced GBA in the sensorimotor cortex was larger for faces expressing fear than for faces expressing anger, which might reflect the facilitation of avoidance-motivated behavior triggered by the concurrent presentation of faces with fearful expressions and painful stimuli. Thus, the presence of emotional cues, like facial expressions from people surrounding us, while receiving acute pain may facilitate neuronal processes involved in the preparation and execution of adequate protective motor responses.

The efficiency of distal needling acupuncture on immediate pain reduction was demonstrated in patients with AC and confirmed the applicability of press tack needles and press tack placebos for double-blind studies in acupuncture. Subsequent clinical application observation proved that results obtained with press tack needles/press tack placebos can be transferred to classical needle acupuncture. Integrating acupuncture with conservative therapy showed superior effectiveness with respect to the time course of the recovery process in AC compared with conservative therapy alone.