- Email: [email protected]
214 THE EFFECT OF PERSONALITY ON CENTRAL PAIN PROCESSING
Poster Sessions / European Journal of Pain 13 (2009) S55–S285
Methods: We performed a randomized controlled study in 12 healthy volunteers aged 21–54 (Md = 25.5) yrs. and paralleled with respect to gender. The study protocol comprised the assessment of dynamic mechanical and thermal pain sensitivity (perceptual wind-up) before and after an IWP (15 N) or hot water immersion trial (HIT; 47.5º C) of 2 min duration. Wind-up was induced either by 10 repetitive (1 Hz) contact heat (49ºC) or ballistic impact stimuli (9 m/s) on the phalanges of the non-dominant hand. Cardiovascular and respiratory activity as well as pain experience were continuously monitored (Biopac Systems, Inc.). Results: The HIT but not the IWP reliably produced a significant mean blood pressure increase of 5% (p = .04). While prominent reductions of ratings for heterotopically applied mechanical and thermal noxious stimuli could be observed during the HIT, this was only the case for thermal test stimuli in the IWP condition. Conclusions: The IWP proved to be a valid paradigm for DNIC induction, unconfounded by BRS-related hypoalgesia. The data also indicate a modality specificity of DNIC in man. The study was supported by grants from the Luxembourg University and the Ministry of Research (AFR TR-PHD BFR07–102). 211 PRELIMINARY EXPERIMENTAL DATA REGARDING THE EFFECTS OF TWO 5HT1 RECEPTOR AGONISTS IN NOCICEPTION L. Tartau *. Gr.T. Popa University of Medicine and Pharmacy, Iasi, Romania Abstract: Serotonin is a major component of the inflammatory chemical milieu and contributes to the pain of tissue injury via an action on multiple receptor subtypes. Buspirone, is a partial 5-HT1 A receptor agonist buspirone which is widely used for treating anxiety. Sumatriptan is a 5HT 1B/1D serotonin receptor agonist use used to treat severe migraine headaches. The aim of the present study was to establish the effects of two 5HT1 serotonine receptor subtype agonists in cutaneous and visceral pain models in mice. Material and method: The experiment was carried out, with white male mice (20–25 g), distributed into 3 groups of 7 animals each, treated intraperitoneally as follows: Group I: saline solution 0.3 ml (Control); Group II (BUS): buspirone 8 mg/kbw; Group III (SUM): sumatriptan 30 mg/kbw. The nociceptive cutaneous testing was performed using hot plate assay. The model of visceral pain consists of inflammatory cystitis after intraperitoneal injection of cyclophosphamide (200 mg/kbw). Data were statistically analyzed using SPSS program. Results: Buspirone significantly increased the response latency in the mouse hot plate test and markedly decreased the nociceptive behavioral manifestations in experimental chemical cystitis model. Sumatriptan increased pain threshold in the model of thermal noxious stimulation, but do not influence painful behavioral manifestations in the visceral pain test. Conclusions: Using the mouse model of acute pain hot plate analgesia meter, we found antinociceptive properties of both buspirone and sumatriptan. Buspirone is antinociceptor, while sumatriptan possesses no analgesic properties, in visceral pain model. 212 BOTH VISCERAL AND SOMATIC ENDOGENOUS PAIN MODULATION ARE ABNORMAL IN IRRITABLE BOWEL SYNDROME (IBS) PATIENTS: A META-ANALYSIS ACROSS DIFFERENT RACES C. Wilder-Smith1,2 *. 1 Brain-Gut Research Group, Bern, Switzerland; 2 Dept Medicine, National University Singapore, Singapore, Singapore Recent psychophysical and brain fMRI studies have shown abnormal endogenous visceral or somatic pain modulation in smaller numbers of IBS patients of different races. In this meta-analysis visceral and somatic pain modulation, specifically diffuse noxious inhibitory controls (DNIC), were compared across different races in a large number of IBS and healthy subjects. DNIC was examined
S69
by heterotopic stimulation using rectal distension (visceral DNIC) or electrical hand stimulation (somatic DNIC) applied alone and together with cold foot stimulation as the conditioning stimulation. DNIC is the change in primary pain during simultaneous application of the conditioning pain. Stimulation intensities were between 50–70 on 0–100 VAS. Mean somatic and visceral DNIC (95%CI) were similar in the 84 IBS patients (decrease in primary pain intensity −0.5 (−5.4–4.4) and −2.6 (−5.9–1.0), resp.) and in the 69 matched healthy controls (−13.4 (−18–−9) and −8.6 (−15–−3), resp., but different between IBS and controls (p < 0.0001). The pooled change in visceral and somatic pain due to DNIC was −6% (−13–1) in IBS and −22% (−28– −17) in controls (p < 0.0001). 54% of IBS patients versus 9% of controls showed pain facilitation instead of the expected inhibition (p < 0.0001). The magnitude of DNIC was influenced by race (white > asian > black, p < 0.001). Both visceral and somatic pain modulation were highly abnormal across all races in this large group of IBS patients, implying a generalised dysfunction of sensory modulation. There are significant racial differences in endogenous pain modulation. Facilitation during heterotopic stimulation is infrequent in controls and is therefore quite specific for IBS. 213 NEURONAL PENTRAXIN 1 CONTRIBUTES TO THE DESCENDING MODULATION OF NEUROPATHIC PAIN A. Zapata1 *, R. Schepers1 , B. Gehrke1 , E. Oh1 , R. Trullas2 , T. Shippenberg1 . 1 National Institute on Drug Abuse, Baltimore, United States; 2 Institut d’Investigacions Biomediques de Barcelona, CSIC/IDIBAPS, Barcelona, Spain Background and Aims: The neuronal pentraxin family of proteins promotes synaptic clustering of AMPA glutamate receptors and synaptic plasticity. Increased glutamatergic signaling in the rostral ventromedial medulla (RVM), a brainstem region important for the descending modulation of nociception, is implicated in the maintenance of neuropathic pain. We have investigated the involvement of neuronal pentraxin 1 (NP1) in a neuropathic pain model in rodents. Methods: We have used gene knock-out techniques and viralmediated silencing/over-expression of NP1 in the RVM in vivo to address the involvement of this protein in the spared nerve injury (SNI) model of neuropathic pain in rodents. Mechanical allodynia (Von Frey filaments) and hyperalgesia (pin prick test) was evaluated in the sural nerve territory of both paws. Results: Mechanical allodynia associated with SNI is reduced in NP1 knock-out mice. Consistent with the role of the RVM in descending facilitation of nerve injury-evoked pain, rescuing NP1 expression therein abolishes the phenotype of knock-out mice. Silencing NP1 in the RVM of rats prior to nerve injury prevents the development of allodynia and hyperalgesia. Furthermore, when silencing occurs after SNI, the expression of allodynia and hyperalgesia is reversed. Modulation of NP1 expression did not change basal nociception in the ipsilateral paw nor alter mechanical thresholds in the contralateral paw after injury. Conclusions: These data demonstrate a specific role of NP1 in the pathogenesis of neuropathic pain and suggest that targeting this protein may provide a novel treatment for persistent pain arising from diverse etiologies. 214 THE EFFECT OF PERSONALITY ON CENTRAL PAIN PROCESSING C. Berna1,2 *, A. Reinecke1 , E.A. Holmes1 , G.M. Goodwin1 , I. Tracey2 . 1 Department of Psychiatry, University of Oxford, Oxford, United Kingdom; 2 Centre for Functional Magnetic Imaging of the Brain (FMRIB), Departments of Clinical Neurology and Anaesthetics, University of Oxford, Oxford, United Kingdom Background and Aims: Neuroticism is a personality trait, predisposing to depression and associated with negative outcomes
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Poster Sessions / European Journal of Pain 13 (2009) S55–S285
in chronic pain patients. Little is known about pain perception in healthy volunteers with high neuroticism scores. Our aim was to use fMRI to investigate differences in central pain processing of a tonic painful stimulus, in young, healthy volunteers with high neuroticism scores, compared to matched low neuroticism scorers. Methods: Neuroticism (N) was assessed with the Eysenck Personality Questionnaire (EPQ). Two age-matched groups of 12 volunteers (high N: mean EPQ: 17, mean age 24.9) (low N: mean EPQ 2.2, mean age 24.4) underwent a functional scan, during which 30-second thermal stimuli of a moderate pain intensity (5/10) were delivered to the arm. Results: The temperature required to obtain a moderate pain intensity rating was not significantly different between the two groups (high N (mean ± SD): 43.92±1.44, mean low 44.25±1.14, p > 0.5). Preliminary fMRI data analysis suggests that, despite no difference in noxious input, high N is associated with more activity in the rACC, mPFC, left IFG and left DLPFC during pain perception, compared to low N. Conclusions: These preliminary results suggest that areas involved in emotion processing and regulation are more activated in young, healthy volunteers with high Neuroticism. An alteration in the function of pathways used for emotion and pain regulation, could explain why a population at risk for depression is also at risk for chronic pain, and hint towards the mechanisms involved in this risk. 215 CEREBRAL PLASTICITY IN PAINFUL PHANTOM LIMB: A STUDY WITH TRANSCRANIAL MAGNETIC STIMULATION AND FUNCTIONAL MAGNETIC RESONANCE IMAGING Y. Sifuentes Almeida de Oliveira1 , E. Talamoni Fonoff1 , M.Gc. ¸ Morais Martin2 , V.P. Araujo1 , M. Jacobsen Teixeira1 , D. Ciampi de Andrade1 *. 1 Institute of Psychiatry Hospital das Cl´ınicas of the University of S˜ ao Paulo (USP), Brazil. Division of Functional Neurosurgery of Institute of Psychiatry, Department of Neurology, USP., S˜ ao Paulo, Brazil; 2 Radiology Department, University of S˜ ao Paulo, Brazil, S˜ ao Paulo, Brazil Background: Cortical reorganization has been mostly studied in limb amputees with associated phantom limb phenomena (PLP) or pain. However, other painful conditions such as brachial plexus avulsion (BPA) may present PLP. We report a case of a painful BPA patient with PLP evaluated by cortical mapping, functional and diffusion tensor MRI (fMRI and DT-MRI) before and after pain treatment. Case report: A 40 year-old male presented with a complete left BPA after a motorcycle accident 20 years ago. He had pain in the deafferented hand associated to PLP. His pain was refractory to pharmacological treatment and did not respond to a radiofrequency (dorsal root entry zone) DREZ-tomy. Cortical mapping performed with navigated Transcranial Magnetic Stimulation (TMS) and fMRI imaging showed an increased ipsilateral M1 hand representation over the primary somatosensory cortex and foot area. DT-MRI focused in the cortico-spinal tract showed that its fibers were connected to adjacent cortical areas beyond M1. After successful treatment trial with repetitive rTMS and a significant pain relief, a new cortical mapping showed a reduction of the hand M1 cortical area representation and the appearance of facial evoked responses, which were not present before treatment. CONCLUSION: Painful PLP by BPA is a complex condition and pain relief may be related to dynamic neuroplasticity changes that can be evaluated by non invasive cortical mapping.
216 SOCIAL SUPPORT MODULATES BRAIN ACTIVATION IN FIBROMYALGIA PATIENTS P. Montoya1 , W. Larbig2 *, C. Sitges1 , R. Veit2 , N. Birbaumer2 . 1 Research Institute on Health Sciences (IUNICS) University of Balearic Islands, Palma, Spain; 2 Institute of Medical Psychology and Behavioral Neurobiology, University of Tuebingen, Tuebingen, Germany Previous research has shown that fibromyalgia is characterized by an abnormal processing of somatosensory information and that pain sensitivity in these patients may be modulated by affective factors. Recently, it has been further observed that affective components of the neural pain network are more activated than sensory components during the experience of another’s pain in healthy controls. In the present study, we investigated whether the presence vs. absence of patient’s significant other may also influence brain activity elicited by non-painful somatosensory stimulation in fibromyalgia. Ten female patients with fibromyalgia (aged 51.2 yrs) and nine female healthy controls (aged 55.3 yrs) were examined using fMRI during the application of vibratory stimuli at the elbow (considered as a tender point in fibromyalgia) and finger (control point). Significant greater activations were found in insula, anterior cingulate cortex (ACC), and secondary somatosensory cortex (SII) in fibromyalgia patients compared to healthy controls only when somatosensory stimuli were applied at the elbow in presence of patient’s significant other, but no when stimuli were applied in absence of patient’s significant other, or when stimuli were applied at the finger. These data suggest that social support from significant others may activate both sensory and affective components of the pain network in fibromyalgia. Furthermore, we concluded that social support could play a relevant role for the maintenance of pain in fibromyalgia. Research was supported by the Spanish Ministerio de Ciencia e Innovacion ´ and European Funds (Plan Nacional de I+D+I; ref.: SEJ2007–62312). 217 fMRI TO INVESTIGATE TREATMENT RESPONSE TO CBT IN PATIENTS WITH CHRONIC PAIN M. Naylor *, M. Krauthamer, G. Cloud, P. Newhouse. University of Vermont, College of Medicine, Burlington, United States Aim: to investigate whether Cognitive Behavioral Therapy (CBT), modifies the dysfunctional neural circuitry associated with chronic pain as examined by functional magnetic resonance imaging (fMRI) using the emotional stimuli (Ekman’s Picture Set and International Affective Picture Set (IAPS). Methods: two step experiment testing: (1) whether there is a difference in amygdala reactivity to emotional stimuli between chronic pain patients and healthy controls; (2) whether the 11week CBT modifies the dysfunctional neural circuitry associated with chronic pain. Nine patients with musculoskeletal chronic pain. Exclusion criteria: Major Depression, Dysthymia, Panic Disorder, PTSD. Controls: healthy controls. Results: Experiment #1: chronic pain patients showed increased amygdala activation relative to controls (p < 0.01) during viewing blocks of Ekman’s and IAPS pictures paradigm. Results suggest that a phenomenon described in PTSD and depression occurs also in chronic pain patients even when they do not meet criteria for PTSD or depression. Experiment #2: chronic pain patients performed the same tasks as in Experiment #1 before and after 11-week CBT. Results showed decreased activation in amygdala and the primary somatosensory cortex (S-1) and increased activation in the Medial Frontal Gyrus after 11-week CBT as compared to baseline (p < 0.01). Furthermore, we found correlations between the postgroup increase in TOPS Life Control Measure and decrease in the amygdala (p = 0.033) and S-1 (p = .002) activations. Conclusion: Our findings suggest that CBT effectively influences dysfunctional neural emotional circuitry in chronic pain patients.
Methods: We performed a randomized controlled study in 12 healthy volunteers aged 21–54 (Md = 25.5) yrs. and paralleled with respect to gender. The study protocol comprised the assessment of dynamic mechanical and thermal pain sensitivity (perceptual wind-up) before and after an IWP (15 N) or hot water immersion trial (HIT; 47.5º C) of 2 min duration. Wind-up was induced either by 10 repetitive (1 Hz) contact heat (49ºC) or ballistic impact stimuli (9 m/s) on the phalanges of the non-dominant hand. Cardiovascular and respiratory activity as well as pain experience were continuously monitored (Biopac Systems, Inc.). Results: The HIT but not the IWP reliably produced a significant mean blood pressure increase of 5% (p = .04). While prominent reductions of ratings for heterotopically applied mechanical and thermal noxious stimuli could be observed during the HIT, this was only the case for thermal test stimuli in the IWP condition. Conclusions: The IWP proved to be a valid paradigm for DNIC induction, unconfounded by BRS-related hypoalgesia. The data also indicate a modality specificity of DNIC in man. The study was supported by grants from the Luxembourg University and the Ministry of Research (AFR TR-PHD BFR07–102). 211 PRELIMINARY EXPERIMENTAL DATA REGARDING THE EFFECTS OF TWO 5HT1 RECEPTOR AGONISTS IN NOCICEPTION L. Tartau *. Gr.T. Popa University of Medicine and Pharmacy, Iasi, Romania Abstract: Serotonin is a major component of the inflammatory chemical milieu and contributes to the pain of tissue injury via an action on multiple receptor subtypes. Buspirone, is a partial 5-HT1 A receptor agonist buspirone which is widely used for treating anxiety. Sumatriptan is a 5HT 1B/1D serotonin receptor agonist use used to treat severe migraine headaches. The aim of the present study was to establish the effects of two 5HT1 serotonine receptor subtype agonists in cutaneous and visceral pain models in mice. Material and method: The experiment was carried out, with white male mice (20–25 g), distributed into 3 groups of 7 animals each, treated intraperitoneally as follows: Group I: saline solution 0.3 ml (Control); Group II (BUS): buspirone 8 mg/kbw; Group III (SUM): sumatriptan 30 mg/kbw. The nociceptive cutaneous testing was performed using hot plate assay. The model of visceral pain consists of inflammatory cystitis after intraperitoneal injection of cyclophosphamide (200 mg/kbw). Data were statistically analyzed using SPSS program. Results: Buspirone significantly increased the response latency in the mouse hot plate test and markedly decreased the nociceptive behavioral manifestations in experimental chemical cystitis model. Sumatriptan increased pain threshold in the model of thermal noxious stimulation, but do not influence painful behavioral manifestations in the visceral pain test. Conclusions: Using the mouse model of acute pain hot plate analgesia meter, we found antinociceptive properties of both buspirone and sumatriptan. Buspirone is antinociceptor, while sumatriptan possesses no analgesic properties, in visceral pain model. 212 BOTH VISCERAL AND SOMATIC ENDOGENOUS PAIN MODULATION ARE ABNORMAL IN IRRITABLE BOWEL SYNDROME (IBS) PATIENTS: A META-ANALYSIS ACROSS DIFFERENT RACES C. Wilder-Smith1,2 *. 1 Brain-Gut Research Group, Bern, Switzerland; 2 Dept Medicine, National University Singapore, Singapore, Singapore Recent psychophysical and brain fMRI studies have shown abnormal endogenous visceral or somatic pain modulation in smaller numbers of IBS patients of different races. In this meta-analysis visceral and somatic pain modulation, specifically diffuse noxious inhibitory controls (DNIC), were compared across different races in a large number of IBS and healthy subjects. DNIC was examined
S69
by heterotopic stimulation using rectal distension (visceral DNIC) or electrical hand stimulation (somatic DNIC) applied alone and together with cold foot stimulation as the conditioning stimulation. DNIC is the change in primary pain during simultaneous application of the conditioning pain. Stimulation intensities were between 50–70 on 0–100 VAS. Mean somatic and visceral DNIC (95%CI) were similar in the 84 IBS patients (decrease in primary pain intensity −0.5 (−5.4–4.4) and −2.6 (−5.9–1.0), resp.) and in the 69 matched healthy controls (−13.4 (−18–−9) and −8.6 (−15–−3), resp., but different between IBS and controls (p < 0.0001). The pooled change in visceral and somatic pain due to DNIC was −6% (−13–1) in IBS and −22% (−28– −17) in controls (p < 0.0001). 54% of IBS patients versus 9% of controls showed pain facilitation instead of the expected inhibition (p < 0.0001). The magnitude of DNIC was influenced by race (white > asian > black, p < 0.001). Both visceral and somatic pain modulation were highly abnormal across all races in this large group of IBS patients, implying a generalised dysfunction of sensory modulation. There are significant racial differences in endogenous pain modulation. Facilitation during heterotopic stimulation is infrequent in controls and is therefore quite specific for IBS. 213 NEURONAL PENTRAXIN 1 CONTRIBUTES TO THE DESCENDING MODULATION OF NEUROPATHIC PAIN A. Zapata1 *, R. Schepers1 , B. Gehrke1 , E. Oh1 , R. Trullas2 , T. Shippenberg1 . 1 National Institute on Drug Abuse, Baltimore, United States; 2 Institut d’Investigacions Biomediques de Barcelona, CSIC/IDIBAPS, Barcelona, Spain Background and Aims: The neuronal pentraxin family of proteins promotes synaptic clustering of AMPA glutamate receptors and synaptic plasticity. Increased glutamatergic signaling in the rostral ventromedial medulla (RVM), a brainstem region important for the descending modulation of nociception, is implicated in the maintenance of neuropathic pain. We have investigated the involvement of neuronal pentraxin 1 (NP1) in a neuropathic pain model in rodents. Methods: We have used gene knock-out techniques and viralmediated silencing/over-expression of NP1 in the RVM in vivo to address the involvement of this protein in the spared nerve injury (SNI) model of neuropathic pain in rodents. Mechanical allodynia (Von Frey filaments) and hyperalgesia (pin prick test) was evaluated in the sural nerve territory of both paws. Results: Mechanical allodynia associated with SNI is reduced in NP1 knock-out mice. Consistent with the role of the RVM in descending facilitation of nerve injury-evoked pain, rescuing NP1 expression therein abolishes the phenotype of knock-out mice. Silencing NP1 in the RVM of rats prior to nerve injury prevents the development of allodynia and hyperalgesia. Furthermore, when silencing occurs after SNI, the expression of allodynia and hyperalgesia is reversed. Modulation of NP1 expression did not change basal nociception in the ipsilateral paw nor alter mechanical thresholds in the contralateral paw after injury. Conclusions: These data demonstrate a specific role of NP1 in the pathogenesis of neuropathic pain and suggest that targeting this protein may provide a novel treatment for persistent pain arising from diverse etiologies. 214 THE EFFECT OF PERSONALITY ON CENTRAL PAIN PROCESSING C. Berna1,2 *, A. Reinecke1 , E.A. Holmes1 , G.M. Goodwin1 , I. Tracey2 . 1 Department of Psychiatry, University of Oxford, Oxford, United Kingdom; 2 Centre for Functional Magnetic Imaging of the Brain (FMRIB), Departments of Clinical Neurology and Anaesthetics, University of Oxford, Oxford, United Kingdom Background and Aims: Neuroticism is a personality trait, predisposing to depression and associated with negative outcomes
S70
Poster Sessions / European Journal of Pain 13 (2009) S55–S285
in chronic pain patients. Little is known about pain perception in healthy volunteers with high neuroticism scores. Our aim was to use fMRI to investigate differences in central pain processing of a tonic painful stimulus, in young, healthy volunteers with high neuroticism scores, compared to matched low neuroticism scorers. Methods: Neuroticism (N) was assessed with the Eysenck Personality Questionnaire (EPQ). Two age-matched groups of 12 volunteers (high N: mean EPQ: 17, mean age 24.9) (low N: mean EPQ 2.2, mean age 24.4) underwent a functional scan, during which 30-second thermal stimuli of a moderate pain intensity (5/10) were delivered to the arm. Results: The temperature required to obtain a moderate pain intensity rating was not significantly different between the two groups (high N (mean ± SD): 43.92±1.44, mean low 44.25±1.14, p > 0.5). Preliminary fMRI data analysis suggests that, despite no difference in noxious input, high N is associated with more activity in the rACC, mPFC, left IFG and left DLPFC during pain perception, compared to low N. Conclusions: These preliminary results suggest that areas involved in emotion processing and regulation are more activated in young, healthy volunteers with high Neuroticism. An alteration in the function of pathways used for emotion and pain regulation, could explain why a population at risk for depression is also at risk for chronic pain, and hint towards the mechanisms involved in this risk. 215 CEREBRAL PLASTICITY IN PAINFUL PHANTOM LIMB: A STUDY WITH TRANSCRANIAL MAGNETIC STIMULATION AND FUNCTIONAL MAGNETIC RESONANCE IMAGING Y. Sifuentes Almeida de Oliveira1 , E. Talamoni Fonoff1 , M.Gc. ¸ Morais Martin2 , V.P. Araujo1 , M. Jacobsen Teixeira1 , D. Ciampi de Andrade1 *. 1 Institute of Psychiatry Hospital das Cl´ınicas of the University of S˜ ao Paulo (USP), Brazil. Division of Functional Neurosurgery of Institute of Psychiatry, Department of Neurology, USP., S˜ ao Paulo, Brazil; 2 Radiology Department, University of S˜ ao Paulo, Brazil, S˜ ao Paulo, Brazil Background: Cortical reorganization has been mostly studied in limb amputees with associated phantom limb phenomena (PLP) or pain. However, other painful conditions such as brachial plexus avulsion (BPA) may present PLP. We report a case of a painful BPA patient with PLP evaluated by cortical mapping, functional and diffusion tensor MRI (fMRI and DT-MRI) before and after pain treatment. Case report: A 40 year-old male presented with a complete left BPA after a motorcycle accident 20 years ago. He had pain in the deafferented hand associated to PLP. His pain was refractory to pharmacological treatment and did not respond to a radiofrequency (dorsal root entry zone) DREZ-tomy. Cortical mapping performed with navigated Transcranial Magnetic Stimulation (TMS) and fMRI imaging showed an increased ipsilateral M1 hand representation over the primary somatosensory cortex and foot area. DT-MRI focused in the cortico-spinal tract showed that its fibers were connected to adjacent cortical areas beyond M1. After successful treatment trial with repetitive rTMS and a significant pain relief, a new cortical mapping showed a reduction of the hand M1 cortical area representation and the appearance of facial evoked responses, which were not present before treatment. CONCLUSION: Painful PLP by BPA is a complex condition and pain relief may be related to dynamic neuroplasticity changes that can be evaluated by non invasive cortical mapping.
216 SOCIAL SUPPORT MODULATES BRAIN ACTIVATION IN FIBROMYALGIA PATIENTS P. Montoya1 , W. Larbig2 *, C. Sitges1 , R. Veit2 , N. Birbaumer2 . 1 Research Institute on Health Sciences (IUNICS) University of Balearic Islands, Palma, Spain; 2 Institute of Medical Psychology and Behavioral Neurobiology, University of Tuebingen, Tuebingen, Germany Previous research has shown that fibromyalgia is characterized by an abnormal processing of somatosensory information and that pain sensitivity in these patients may be modulated by affective factors. Recently, it has been further observed that affective components of the neural pain network are more activated than sensory components during the experience of another’s pain in healthy controls. In the present study, we investigated whether the presence vs. absence of patient’s significant other may also influence brain activity elicited by non-painful somatosensory stimulation in fibromyalgia. Ten female patients with fibromyalgia (aged 51.2 yrs) and nine female healthy controls (aged 55.3 yrs) were examined using fMRI during the application of vibratory stimuli at the elbow (considered as a tender point in fibromyalgia) and finger (control point). Significant greater activations were found in insula, anterior cingulate cortex (ACC), and secondary somatosensory cortex (SII) in fibromyalgia patients compared to healthy controls only when somatosensory stimuli were applied at the elbow in presence of patient’s significant other, but no when stimuli were applied in absence of patient’s significant other, or when stimuli were applied at the finger. These data suggest that social support from significant others may activate both sensory and affective components of the pain network in fibromyalgia. Furthermore, we concluded that social support could play a relevant role for the maintenance of pain in fibromyalgia. Research was supported by the Spanish Ministerio de Ciencia e Innovacion ´ and European Funds (Plan Nacional de I+D+I; ref.: SEJ2007–62312). 217 fMRI TO INVESTIGATE TREATMENT RESPONSE TO CBT IN PATIENTS WITH CHRONIC PAIN M. Naylor *, M. Krauthamer, G. Cloud, P. Newhouse. University of Vermont, College of Medicine, Burlington, United States Aim: to investigate whether Cognitive Behavioral Therapy (CBT), modifies the dysfunctional neural circuitry associated with chronic pain as examined by functional magnetic resonance imaging (fMRI) using the emotional stimuli (Ekman’s Picture Set and International Affective Picture Set (IAPS). Methods: two step experiment testing: (1) whether there is a difference in amygdala reactivity to emotional stimuli between chronic pain patients and healthy controls; (2) whether the 11week CBT modifies the dysfunctional neural circuitry associated with chronic pain. Nine patients with musculoskeletal chronic pain. Exclusion criteria: Major Depression, Dysthymia, Panic Disorder, PTSD. Controls: healthy controls. Results: Experiment #1: chronic pain patients showed increased amygdala activation relative to controls (p < 0.01) during viewing blocks of Ekman’s and IAPS pictures paradigm. Results suggest that a phenomenon described in PTSD and depression occurs also in chronic pain patients even when they do not meet criteria for PTSD or depression. Experiment #2: chronic pain patients performed the same tasks as in Experiment #1 before and after 11-week CBT. Results showed decreased activation in amygdala and the primary somatosensory cortex (S-1) and increased activation in the Medial Frontal Gyrus after 11-week CBT as compared to baseline (p < 0.01). Furthermore, we found correlations between the postgroup increase in TOPS Life Control Measure and decrease in the amygdala (p = 0.033) and S-1 (p = .002) activations. Conclusion: Our findings suggest that CBT effectively influences dysfunctional neural emotional circuitry in chronic pain patients.