Amadeo M, Roemer R A, Shagass C
Biol Psychiatry. 1977 Apr;12(2):289-97.
Filbey and Gazzaniga (1969) found that verbal reaction times were shorter to right than to left visual field stimuli. They interpreted this reaction time difference (30 to 40 msec) to reflect callosal transmission time, i.e., the delay required for information received in the right hemisphere to be acted upon by the verbal left hemisphere. We have performed four verbal reaction time experiments with normal subjects, utilizing differing hemifield stimulus presentations and task requirements. Stimuli were: small lights (light-emitting diodes); checkerboard pattern briefly flashed; small circles; consonant-vowel-consonant triads, either meaningful or nonsense. Contrary to Filbey and Gazzaniga's observations, we found no difference between verbal reaction times to left and right half-field presentations, or a significantly shorter reaction time with left-field presentations, depending upon experimental conditions. Faster reaction times with left-field stimuli were found in left-handed as well as right-handed subjects. Our data indicate that it may be premature to infer callosal speed of transmission from verbal reaction times to half-field stimuli. The paradoxical finding of faster verbal reactions to right hemisphere visual inputs does not appear to be related to handedness, and it occurs with meaningful stimuli; this finding remains unexplained.
菲尔贝和加扎尼加（1969年）发现，对右侧视野刺激的言语反应时间比对左侧视野刺激的要短。他们将这种反应时间差异（30至40毫秒）解释为胼胝体传递时间的反映，即右半球接收到的信息被左侧言语半球处理所需的延迟。我们对正常受试者进行了四项言语反应时间实验，采用了不同的半视野刺激呈现方式和任务要求。刺激物包括：小灯（发光二极管）；短暂闪烁的棋盘图案；小圆圈；有意义或无意义的辅音-元音-辅音三联体。与菲尔贝和加扎尼加的观察结果相反，我们发现根据实验条件，对左半视野和右半视野呈现的言语反应时间没有差异，或者左视野呈现时反应时间明显更短。在左撇子和右撇子受试者中都发现了左视野刺激时更快的反应时间。我们的数据表明，从言语反应时间到半视野刺激推断胼胝体的传递速度可能为时过早。对右半球视觉输入的言语反应更快这一矛盾的发现似乎与用手习惯无关，并且在有意义的刺激下也会出现；这一发现仍无法解释。
