The effects of deefferentation without deafferentation on functional connectivity in patients with facial palsy.
Cerebral plasticity includes the adaptation of anatomical and functional connections between parts of the involved brain network. However, little is known about the network dynamics of these connectivity changes. This study investigates the impact of a pure deefferentation, without deafferentation or brain damage, on the functional connectivity of the brain. To investigate this issue, functional MRI was performed on 31 patients in the acute state of Bell's palsy (idiopathic peripheral facial nerve palsy). All of the patients performed a motor paradigm to identify seed regions involved in motor control. The functional connectivity of the resting state within this network of brain regions was compared to a healthy control group. We found decreased connectivity in patients, mainly in areas responsible for sensorimotor integration and supervision (SII, insula, thalamus and cerebellum). However, we did not find decreased connectivity in areas of the primary or secondary motor cortex. The decreased connectivity for the SII and the insula significantly correlated to the severity of the facial palsy. Our results indicate that a pure deefferentation leads the brain to adapt to the current compromised state during rest. The motor system did not make a major attempt to solve the sensorimotor discrepancy by modulating the motor program.
Hans Berger Clinic of Neurology, Jena University Hospital, Germany.
Carsten M
CM
Klingner
Department of Otorhinolaryngology, Jena University Hospital, Germany.
Gerd F
GF
Volk
Hans Berger Clinic of Neurology, Jena University Hospital, Germany.
Stefan
S
Brodoehl
Hans Berger Clinic of Neurology, Jena University Hospital, Germany.
Otto W
OW
Witte
Department of Otorhinolaryngology, Jena University Hospital, Germany.
Orlando
O
Guntinas-Lichius
D000328:Adult; D000344:Afferent Pathways / Q000502:physiology; D000368:Aged; D020330:Bell Palsy / Q000175:diagnosis* / Q000503:physiopathology*; D004525:Efferent Pathways / Q000502:physiology; D005152:Facial Muscles / Q000294:innervation* / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D055815:Young Adult
Facial palsy; Functional connectivity; Plasticity; Resting state; fMRI