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Abstract Introduction Psychoeducational counselling and residual inhibition therapy (RIT) are traditional approaches used in many clinics to manage tinnitus. However, neurophysiological studies to evaluate posttreatment perceptual and functional cortical changes in humans are scarce. Objectives The present study aims to explore whether cortical auditory-evoked potentials (CAEPs; N1 and P3) reflect the effect of modified RIT and psychoeducational counselling, and whether there is a correlation between the behavioral and electrophysiological measures. Methods Ten participants with continuous and bothersome tinnitus underwent a session of psychoeducational counselling and modified RIT. Perceptual measures and CAEPs were recorded pre- and posttreatment. Further, the posttreatment measures were compared with age and gender-matched historical control groups. Results Subjectively, 80% of the participants reported a reduction in the loudness of their tinnitus. Objectively, there wasasignificant reductioninthe posttreatment amplitude of N1 and P3, with no alterations in latency. There was no correlation between the perceived difference in tinnitus loudness and the difference in P3 amplitude (at Pz). Conclusion The perceptual and functional (as evidenced by sensory, N1, and cognitive, P3 reduction) changes after a single session of RIT and psychoeducational counselling are suggestive of plastic changes at the cortical level. The current study serves as preliminary evidence that event-related potentials (ERPs) can be used to quantify the physiological changes that occur after the intervention for tinnitus.
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Objective To investigate the efficacy of acupuncture and rehabilitation therapy on lower limb motor function, and to explore a cortical mechanism using functional near infrared spectroscopy (fNIRS). Methods From December, 2020 to July, 2021, 24 stroke patients with lower limb motor dysfunction in our hospital were randomly divided into rehabilitation group (n = 12) and acupuncture-rehabilitation group (n = 12), and received routine rehabilitation training and acupuncture-rehabilitation intervention for four weeks, respectively. The control group included ten healthy subjects matched the patients. Before and after intervention, the lower limb motor function of the patients was assessed with Fugl-Meyer Assessment-Lower Extremities (FMA-LE), and all the subjects accepted fNIRS examination. The functional intensity and lateralization index (LI) of supplementary motor area (SMA), premotor cortex (PMC) and sensory motor cortex (SMC) were calculated based on oxygenated hemoglobin (HbO2). Results There was no significant difference in FMA-LE score between the rehabilitation group and the acupuncture-rehabilitation group before the intervention (P > 0.05). After four weeks of intervention, FMA-LE scores improved in both groups (t > 3.770, P 0.05). After intervention, the average functional connection increased in both groups (t > 2.178, P < 0.05), and the functional connection of the affected PMC of acupuncture-rehabilitation group increased (P < 0.05). The LI in SMC increased in the acupuncture-rehabilitation group (P < 0.05). There was a significant positive correlation between the change of functional connection of the affected PMC and the change of FMA-LE scores in the acupuncture-rehabilitation group (r = 0.579, P < 0.05). Conclusion Acupuncture with rehabilitation therapy can significantly improve the lower limb motor function and asymmetrical activation of SMC in stroke patients. The recovery of lower limb motor function may be related to the enhanced activation of affected PMC.
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BACKGROUND: Blood oxygenation level dependent functional MRI (BOLD-fMRI) has proven to be a powerful tool for studying the functional change of the brain. In task-state fMRI study, the functional reorganization of sensory and motor cortex has been observed in patients with cervical spondylotic myelopathy. OBJECTIVE: To discuss the correlations between task-state fMRI measurements with clinical symptoms and surgical outcomes of cervical spondylotic myelopathy. METHODS: Eighty-two patients with cervical spondylotic myelopathy undergoing posterior cervical decompression (cervical spondylotic myelopathy group) and forty-five healthy volunteers (normal group) were recruited from January 2018 to January 2019. All subjects underwent fMRI and performed a finger-tapping paradigm with the right hand. The Japanese Orthopaedic Association score was used to evaluate the function of the spinal cord. Japanese Orthopaedic Association score recovery rate less than 50% was defined as a poor result. RESULTS AND CONCLUSION: (1) Japanese Orthopaedic Association score was significantly improved after surgery in the cervical spondylotic myelopathy group compared with that before surgery (P 0.05). Before surgery, VOA ratio (left precentral gyrus/left postcentral gyrus) was significantly higher in the cervical spondylotic myelopathy group than in normal group (P 0.05). VOA ratio was significantly decreased compared with that preoperatively (P < 0.05). (4) Correlation analysis revealed that the VOA in the left precentral gyrus and left postcentral gyrus and VOA ratio were significantly correlated with preoperative Japanese Orthopaedic Association score and postoperative Japanese Orthopaedic Association score recovery rate (P < 0.05). The absolute value of correlation coefficient of VOA ratio with preoperative Japanese Orthopaedic Association score and postoperative recovery rate was largest. (5) Receiver operating characteristic curve analysis showed that the area under the curve value for the VOA ratio was 0.803, indicating strong predictive discrimination, and the cut-off value was 3.621. The area under the curve value for Japanese Orthopaedic Association score was 0.751, and the cut-off value was 8. The predictive effect of VOA ratio was higher than Japanese Orthopaedic Association score. (6) The results indicate that the VOA in the left precentral gyrus and left postcentral gyrus was negatively correlated with severity of clinical symptoms (Japanese Orthopaedic Association score). Preoperative VOA ratio can effectively predict the recovery of spinal cord function after operation in patients with cervical spondylotic myelopathy.
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Objective@#To explore the correlations relating functional MRI (fMRI) and diffusion tensor imaging (DTI) parameters with pre-operative neurological status and post-operative outcomes for patients with cervical spondylotic myelopathy (CSM).@*Methods@#Eighty-seven CSM patients treated with surgical decompression and 38 healthy counterparts were enrolled as the CSM and control groups respectively. DTI and fMRI of the cervical spine were performed while the subjects performed a finger-tapping task with their right hands before the operation and 6 months later. The control group was evaluated only when they were enrolled. All of the patients were given systematic rehabilitation treatment after the surgery. The Japanese Orthopaedic Association (JOA) scoring system for CSM was used to evaluate neurological status, and a JOA recovery rate <50% was defined as a poor recovery.@*Results@#Compared with the healthy controls, the pre-operative patients showed significantly higher volume of activation (VOA) in the left precentral gyrus (PrCG), but that had decreased significantly 6 months after the surgery. Before the surgery, the patients′ fractional isotropy (FA) was significantly less than that of the controls, but it had increased significantly 6 months after the operation. There was no difference in VOA in the left postcentral gyrus (PoCG) between the CSM patients and the controls before the surgery. The VOA ratio (PrCG/PoCG), VOA-PrCG, VOA-PoCG and FA were significantly correlated with both the JOA scores and recovery rates. Receiver operating characteristic (ROC) curve analyses were performed for the predictive ability with respect to surgical outcomes. The largest area under the ROC curve was observed for the VOA ratio (0.805), followed by FA (0.740), and the VOA-PrCG (0.715). The fMRI and DTI showed better potential for predicting functional outcomes than with standard MRI parameters. Multivariate logistic regression revealed that the VOA ratio and FA were independently associated with poor outcomes.@*Conclusions@#fMRI and DTI parameters may be more valuable than conventional MRI results for neurological assessment and prognosis with CSM patients. They can also provide references for making up rehabilitation plans.
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Objective To explore the correlations relating functional MRI ( fMRI) and diffusion tensor imaging ( DTI) parameters with pre-operative neurological status and post-operative outcomes for patients with cervi-cal spondylotic myelopathy ( CSM ) . Methods Eighty-seven CSM patients treated with surgical decompression and 38 healthy counterparts were enrolled as the CSM and control groups respectively. DTI and fMRI of the cervical spine were performed while the subjects performed a finger-tapping task with their right hands before the operation and 6 months later. The control group was evaluated only when they were enrolled. All of the patients were given systematic rehabilitation treatment after the surgery. The Japanese Orthopaedic Association ( JOA) scoring system for CSM was used to evaluate neurological status, and a JOA recovery rate <50％ was defined as a poor recovery. Results Compared with the healthy controls, the pre-operative patients showed significantly higher volume of acti-vation ( VOA) in the left precentral gyrus ( PrCG) , but that had decreased significantly 6 months after the surgery. Before the surgery, the patients' fractional isotropy ( FA) was significantly less than that of the controls, but it had increased significantly 6 months after the operation. There was no difference in VOA in the left postcentral gyrus (PoCG) between the CSM patients and the controls before the surgery. The VOA ratio (PrCG/PoCG), VOA-PrCG, VOA-PoCG and FA were significantly correlated with both the JOA scores and recovery rates. Receiver oper-ating characteristic ( ROC) curve analyses were performed for the predictive ability with respect to surgical out-comes. The largest area under the ROC curve was observed for the VOA ratio (0.805), followed by FA (0.740), and the VOA-PrCG (0.715). The fMRI and DTI showed better potential for predicting functional outcomes than with standard MRI parameters. Multivariate logistic regression revealed that the VOA ratio and FA were independ-ently associated with poor outcomes. Conclusions fMRI and DTI parameters may be more valuable than conven-tional MRI results for neurological assessment and prognosis with CSM patients. They can also provide references for making up rehabilitation plans.
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Objective To measure the efficacy of combining motor imagery training ( MIT) with convention-al therapy in improving stroke patients′upper-extremity function. And to seek a cortical reorganization mechanism as-sociated with the improvement using resting-state functional magnetic resonance imaging ( rs-fMRI) . Methods Ten stroke survivors were selected as an experimental group. They were given motor imagery training for four weeks ( 30 minutes a day, 5 days a week) and conventional rehabilitation therapy ( 40 minutes a day, 5 days a week) . Another 10 healthy counterparts were the control group. Before and after the four weeks of treatment, both groups were as-sessed using the upper extremity Fugl-Meyer assessment ( FMA-UE) and the modified Barthel index ( MBI) . Moreo-ver, rs-fMRI was conducted to assess functional connectivity between cortical regions and the ipsilesional primary mo-tor cortex ( M1) before and after the intervention. The laterality index ( LI) of the primary motor or sensory cortex was also calculated. Results After the intervention, the average FMA-UE and MBI scores of the experimental group had increased significantly. After MIT and conventional therapy there was increased functional connectivity between the ip-silesional and contralesional M1 areas, and between the ipsilesional M1 and contralesional primary sensory cortex ( S1) and frontal lobe, the functional connection between the ipsilesional M1 and the ipsilesional paracentral lobule and the anterior cingutate was also increased. More specifically, the LI relating M1 and S1 decreased after the inter-vention, tending toward the normal level. LIMI decreased significantly. Conclusion The 4-week regimen of motor imagery training and conventional therapy resulted in functional improvement in the upper limbs and greater ability in the activities of daily living. The observed improvements may be due to cortical reorganization, including better func-tional connectivity between the bilateral M1 areas and increased connectivity between the ipsilesional M1 area and some non-motor areas. There is some recovery of symmetry in the bilateral primary motor cortex.
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Objective To study cerebral cortical activation preoperatively and postoperatively in patients with cervical spondylotic myelopathy (CSM), and discuss effect of the surgery on cortical reorganization in functional recovery.Methods 19 cases with CSM intrial group underwent cervical vertebra canal decompression surgery according to clinical routine.Cases in trial group completed clinical assessment using the modified Japanese Orthopaedic Association Scores (mJOA) prior to decompression and 12 months following surgery, and underwent cerebral functional MRI and conventional MRI in the same time.19 controls also carried out cerebral functional MRI and conventional MRI.All subjects performed a finger-tapping paradigm with right hand during processing functional MRI.The imagings and data of trial group were divided into preoperative group and postoperative group in accordance with the time of completed and than analysed.Results The mJOA score of postoperative group was increased significantly (P<0.001).Cortical volume of activation (VOA) of preoperative group was significantly higher than the control group (P<0.05).VOA was lower in the postoperative group, but still significantly higher than the control group (P<0.05).The preoperative group was able to detect and activate the signal only in the left precentral gyrus.The postoperative group was able to detect and activate the signal in the l left postcentral gyrus, the premotor area and the supplementary motor area, and the right cerebral cortex could also detect a small amount of activation signal.Conclusion CSM patients undergo cerebral cortical remodeling, causing sensory and motor function activation areas to expand and shift.The changes of cortical reorganization after cervical vertebra canal decompression surgery are associated with functional recovery.The surgical treatment may promote the compensating cortical reorganization.
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Objective: The aim of this narrative review is to examine the available literature related to central sensitization (CS) and altered central pain processing in chronic low back pain (CLBP) patients. Methodology: Literature was searched using many electronic databases. Additionally, reference list of most prominent articles were searched to increase the search accuracy, as much as possible. Studies which are evaluating the concept of CS in conservatively treated CLBP patients were included. Results: Results of studies evaluating the responsiveness to various types of stimuli in CLBP patients are contradictory. Some studies in CLBP patients have showed increased pain responses after sensory stimulation of body parts outside the painful region, when some other studies report no differences between patients and healthy controls. Studies evaluating the integrity of the endogenous pain inhibitory systems describe unchanged activity of this descending inhibitory system. Conversely, studies examining brain structure and function in connection with experimentally induced pain provide initial proof for changed central pain processing in CLBP patients. Also inappropriate beliefs about pain, depression and/or pain catastrophizing, may lead to the development of CS. Conclusion: Most of the literatures suggest that the CNS becomes centrally sensitized in a subgroup of patients with CLBP. However, the significance of this involvement is just starting to become clearer. This could be an active topic of future research. More studies are necessary for providing definite evidence for the clinical importance of CS.
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The patients suffering with complex regional pain syndrome (CRPS) reveal sensory, motor and autonomic abnormalities. The pathogenesis of CRPS is poorly understood. Some recent studies have reported that the functional magnetic resonance image (fMRI) findings support that cortical reorganization occurred in the patients with CRPS. We compared the cortical responses on fMRI in a 54-year-old right-handed male patient who suffered with type 2 CRPS on his left hand following an injury 4 years ago. He complained of severe pain and allodynia on the left hand that spread up to the left chest, and he showed abnormal involuntary movement and significant hypothermia on the left hand. The fMRI findings, when a mechanical stimulus was applied on both hands with a brush, showed significantly increased abnormal cortical responses on the primary and secondary somatosensory areas and the distinct parietal association area on the contra-lateral side of the brain to the stimuli on the affected painful hand relative to the stimuli on the unaffected hand. We report on the fMRI findings showing the cortical reorganization in a patient with type 2 CRPS.
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Humans , Male , Middle Aged , Brain , Dyskinesias , Hand , Hyperalgesia , Hypothermia , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Stress, Psychological , ThoraxABSTRACT
A 63-year-old man was admitted with newly developed left hemiparesis. He had experienced left hemiparesis that had resulted from an earlier right thalamic hemorrhage. Diffusion-weighted images showed only high signal intensity lesion in the left internal capsule. Ipsilateral motor evoked potentials were obtained at the affected hand muscles when the unaffected motor cortex was stimulated. This suggests that cortical reorganization in the unaffected hemisphere after the first stroke may be involved in the occurrence of such symptom.
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Humans , Middle Aged , Evoked Potentials, Motor , Hand , Hemorrhage , Internal Capsule , Motor Cortex , Muscles , Paresis , StrokeABSTRACT
The effect of the developed symmetric upper extremity motion trainer on the cortical activation pattern was investigated in three chronic hemiparetic patients using both fMRI and Fugl-Meyer test. The training program was performed at 1 hr/day, 5 days/week during 6 weeks. Fugl-Meyer tests were performed every two weeks during the training. fMRI was performed at 3T scanner with wrist flexion-extension in two different tasks before and after the training program: the only unaffected hand movement (Task 1) and passive movements of affected hand by the active movement of unaffected hand (Task 2). fMRI studies in Task 1 showed that cortical activations decreased in ipsilateral SMC but increased in contralateral SMC. Task 2 showed cortical reorganizations in bilateral SMC, PMA and SMA. Therefore, it seems that the cortical reorganization in chronic hemiparetic patients can be induced by the training with the developed symmetric upper extremity motion trainer.
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Humans , Brain Injuries , Brain , Education , Hand , Magnetic Resonance Imaging , Recovery of Function , Upper Extremity , WristABSTRACT
OBJECTIVE: To investigate whether the somatosensory cortical excitability could be modulated by repetitive electrical stimulation (RES) on the tibial nerve at human ankle joint. METHOD: The subjects were 10 healthy volunteers. The study was composed of 3 sessions: first session, baseline evaluation; second session, RES with a intensity for proprioceptive stimulation on tibial nerve at the right ankle for 3 different duration of 30 minutes, 1 hour, and 2 hours; third session, repeat of baseline evaluation after RES (post- RES evaluation). The baseline evaluation include somatosensory evoked potential study with stimulation of right tibial nerve and compound muscle action potential (CMAPs) of tibial nerve recorded at abductor hallucis and H reflex. The amplitude of each study were measured and compared between baseline evaluation and post-RES evaluation using Kruscal-Wallis test. RESULT: There was no significant change in amplitudes of SSEP, CMAP and H reflex between baseline evaluation and post-RES evaluation of 30 minutes, 1 hour and 2 hours. CONCLUSION: This study suggests that chronic repetitive proprioceptive afferent nerve stimulations could not modulate primary somatosensory cortex in healthy subjects. However, we could not rule out the limitations of sensitivity of somatosensory evoked potential study.