In this study,we investigated orientation selectivity in cat primary visual cortex(V1) and its relationship with various parameters.We found a strong correlation between circular variance(CV) and orthogonal-topreferred response ratio(O/P ratio),and a moderate correlation between tuning width and O/P ratio.Moreover,the suppression far from the peak that accounted for the lower CV in cat V1 cells also contributed to the narrowing of the tuning width of cells.We also studied the dependence of orientation selectivity on the modulation ratio for each cell,which is consistent with robust entrainment of the neuronal response to the phase of the drifting grating stimulus.In conclusion,the CV(global measure) and tuning width(local measure) are significantly correlated with the modulation ratio.
To listen to brain activity as a piece of music,we previously proposed scale-free brainwave music(SFBM)technology,which translated the scalp electroencephalogram(EEG)into musical notes according to the power law of both the EEG and music.In this study,the methodology was further extended to ensemble music on two channels from the two hemispheres.EEG data from two channels symmetrically located on the left and right hemispheres were translated into MIDI sequences by SFBM,and the EEG parameters modulated the pitch,duration and volume of each note.Then,the two sequences were filtered into an ensemble with two voices:the pentatonic scale(traditional Chinese music)or the heptatonic scale(standard Western music).We demonstrated differences in harmony between the two scales generated at different sleep stages,with the pentatonic scale being more harmonious.The harmony intervals of this brain ensemble at various sleep stages followed the power law.Compared with the heptatonic scale,it was easier to distinguish the different stages using the pentatonic scale.These results suggested that the hemispheric ensemble can represent brain activity by variations in pitch,tempo and harmony.The ensemble with the pentatonic scale sounds more consonant,and partially reflects the relations of the two hemispheres.This can be used to distinguish the different states of brain activity and provide a new perspective on EEG analysis.
