Evaluation of early and late presented tasks in the intracarotid Amytal test for epileptic patients.

The temporal relation between speech and somatomotor effects was analyzed in 24 epileptic patients who underwent bilateral intracarotid Amytal tests. Furthermore, a chronological study of the task presentation was carried out. The memory test included 3 pre- and 12 post-injection items, the latter consisting of 6 words and 6 concrete pictures. Both hemispheres had low free verbal recall capacity. The speech-dominant hemisphere recognized 45% of the words and 58% of the pictures; the non-dominant side 17% and 32%, respectively. An epileptic lesion in the right temporal lobe only reduced the word recognition at a statistically significant level. Despite the early start of task presentation, both hemispheres recognized the early items almost as well as those presented later. This makes it possible for an extensive test battery which in turn helps to quantify memory capacity. If this method is used to test hemisphere memory, the possibility of interhemispheric cooperation is reduced, thereby increasing the validity of the results. The results are discussed in relation to intra- and interhemispheric communication during amobarbital sedation and regression.