EEG Alpha Characteristics In Eyes-closed And Eyes-Open Resting-States In Adult Males With Traumatic Spinal Cord Injury

Objectives:To investigate changes of alpha power spectral density,amplitudes and peak frequencies of peak amplitudes in eyes-closed and eyes-open resting-states in male adults with paraplegia due to traumatie spinal eord injury.Method:19 patients with traumatic paraplegia and 15 healthy controls meeting inclusion and exclusion criteria were recruited.500Hz was chosen as sampling frequency,signals between 1 Hz and 100 Hz were passed and bilateral mastoids were selected as reference electrodes.Anterior frontal electrodes AFp3h,AFp4h,AFF3,AFFz,AFF4,frontal central electrodes FCC3,FCCl,FCCz,FCC2,FCC4,central parietal electrodes CPP5h,CPP3h,CPP3h5 CPPz,CPP4h,CPP4,CPP6h,parietal occipital electrodes POO7,POO8 and occipital electrode Oz were used.Each Subject sitting in a wheelchair or chair was wearing wireless dry electrode EEG cap.Three minutes' eyes-open and eyes-closed resting-states electroencephalogran(EEG)signals were collected respectively after signals were stable,one minute's break was taken between two states.Software EEGLAB was used to analyze the EEG data,alpha signals were extracted,independent component analysis(ICA)was performed and noise signals were eliminated.Power spectral density,amplitudes as well as frequencies of peak amplitudes in eyes-open and eyes-closed states were calculated and compared with independent t test and paired sample t test.Results:The alpha power spectral density and amplitudes between patients with spinal cord injury and healthy controls were not statistically different in both eyes-closed and eyes-open resting-states(p>=0.05),but they were generally higher in spinal cord injury patients.Alpha power spectral density and amplitudes between two states of healthy controls were significantly different in anterior frontal,central parietal,parietal occipital and occipital areas,but not in frontal central area(p>=0.05).In patients with spinal cord injury,power spectral density and amplitudes were significantly different between two states(p<0.05),except in AFFz(p>=0.05).Frequencies of peak amplitudes in eyes-open state were significantly higher in FCC3,CPPz,CPP6h,POO8 in patients with spinal cord injury(p<0.05),they were not significantly different in all electrodes in eyes-closed state between two groups(p>=0.05).However,Frequencies of peak amplitudes were generally higher in patients in both states.For healthy controls,frequencies of peak amplitudes between two states were significantly different in anterior frontal,central parietal,parietal occipital and occipital areas(p<0.05)3 but not in frontal central area(p>=0.05),no significant differences between two states were found in all electrodes in patients(p>=0.05).Conclusions:In male adults with traumatic spinal cord injury,power spectral density,amplitudes and frequencies of peak amplitudes were generally higher in both eyes-closed and eyes-open resting-states,the differences of power spectral density,amplitudes between two states were also larger,especially in frontal central area.Besides,differences between two states in frequencies of peak amplitudes in anterior frontal,central parietal,parietal occipital and occipital areas disappeared in patients.All results above indicate that,after spinal cord injury,central nervous system would remodel functionally and compensatorily,visual system would compensate for somatosensory dysfunction,information processing efficiency in central nervous system would be higher and cognition function would improve.