Activation in parietal operculum parallels motor recovery in stroke

• Published in: Human brain mapping Vol. 33; no. 3; pp. 534 - 541
• Main Authors: Forss, Nina, Mustanoja, Satu, Roiha, Kristina, Kirveskari, Erika, Mäkelä, Jyrki P., Salonen, Oili, Tatlisumak, Turgut, Kaste, Markku
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.03.2012; Wiley-Liss; John Wiley & Sons, Inc
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Cognition. Intelligence; Evoked Potentials, Somatosensory - physiology; Female; Functional Laterality - physiology; Fundamental and applied biological sciences. Psychology; Humans; Intellectual and cognitive abilities; Investigative techniques, diagnostic techniques (general aspects); Magnetoencephalography; Male; Medical sciences; Middle Aged; Nervous system; parietal operculum; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Radiodiagnosis. Nmr imagery. Nmr spectrometry; recovery; Recovery of Function - physiology; secondary somatosensory cortex; Somatosensory Cortex - physiopathology; somatosensory evoked fields; stroke; Stroke - physiopathology; Stroke; Nervous system diseases; Radiodiagnosis; Magnetoencephalography; Central nervous system; Cardiovascular disease; somatosensory evoked fields; Operculum; Recovery; Encephalon; Cerebral disorder; Vascular disease; Somatosensory cortex; secondary somatosensory cortex; parietal operculum; Somesthetic pathway; Central nervous system disease; Parietal; Cerebrovascular disease
• DOI: 10.1002/hbm.21230
• ISSN: 1065-9471

Motor recovery after stroke requires continuous interaction of motor and somatosensory systems. Integration of somatosensory feedback with motor programs is needed for the automatic adjustment of the speed, range, and strength of the movement. We recorded somatosensory evoked fields (SEFs) to tactile finger stimulation with whole‐scalp magnetoencephalography in 23 acute stroke patients at 1 week, 1 month, and 3 months after stroke to investigate how deficits in the somatosensory cortical network affect motor recovery. SEFs were generated in the contralateral primary somatosensory cortex (SI) and in the bilateral parietal opercula (PO) in controls and patients. In the patients, SI amplitude or latency did not correlate with any of the functional outcome measures used. In contrast, the contralateral PO (cPO) amplitude to the affected hand stimuli correlated significantly with hand function in the acute phase and during recovery; the weaker the PO activation, the clumsier the hand was. At 1 and 3 months, enhancement of the cPO activation paralleled the improvement of the hand function. Whole‐scalp magnetoencephalography measurements revealed that dysfunction of somatosensory cortical areas distant from the ischemic lesion may affect the motor recovery. Activation strength of the PO paralleled motor recovery after stroke, suggesting that the PO area is an important hub in mediating modulatory afferent input to motor cortex. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.