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应用５Ｈｚ，７．５Ｈｚ，１０Ｈｚ和１５Ｈｚ的图形翻转刺激，记录６０例（１０１只眼）正常人和１７例（２９只眼）老年黄斑变性的稳态图形视诱发电位（ｓｔｅａｄｙ－ｓｔａｔｅｐａｔｔｅｒｎｖｉｓｕａｌｅｖｏｋｅｄｐｏｔｅｎｔｉａｌ，ＳＳＰＶＥＰ）。经离散傅里叶转换（ｄｉｓｃｒｅｔｅＦｏｒｕｉｅｒｔｒａｒｉｓｆｏｒｍ，ＤＦＴ），提取二次谐波、四次谐波的幅值和相位，结果表明：正常人随刺激频率的升高，各频率谐波的振幅逐渐递减，二次谐波与四次谐波振幅的比值呈递增关系；男性的振幅比女性低；５Ｈｚ和７．５Ｈｚ的谐波相位变异较小。老年黄斑变性显示各刺激频率的二次谐波幅值降低，５０％以上患眼呈５Ｈｚ和７．５Ｈｚ的二次和四次谐波相位异常，稳态ＰＶＦＰ时间调谐特性为本病提供了更多视功能变异的信息。
The steady-state pattern evoked potentials (SSPVEP) of 60 patients (101 eyes) and 17 eyes (29 eyes) with age-related macular degeneration were recorded using 5 Hz, 7.5 Hz, 10 Hz and 15 Hz graph inversion stimuli . The amplitude and phase of the second harmonic and the fourth harmonic were extracted by discrete Fourier transform (DFT). The results showed that with the increase of the stimulus frequency, the amplitudes of the harmonics of each frequency gradually decreased. The ratio of the subharmonic to the fourth harmonic amplitude showed an increasing relationship; the amplitude of the male was lower than that of the female; the harmonic phase variations of 5Hz and 7.5Hz were smaller. Age-related macular degeneration showed a decrease in the magnitude of the second harmonic at each stimulus frequency, with second and fourth harmonic phase anomalies of 5 Hz and 7.5 Hz in more than 50% of affected eyes, and steady-state PVFP time-tuning properties provided more Multi-visual function of variation information.