RESUMO
The present study investigated implicit memory during general anaesthesia in patients with elective surgery on the cervical or lumbar spine. A total of 37 patients were investigated, together with 59 healthy control subjects. The patients were divided into two groups. One group heard repeated presentations of common words (animals, flowers, countries) during anaesthesia. The other patient group heard only pink noise during anaesthesia. After surgery, all patients were asked spontaneously to name three countries, flowers, and animals. The healthy control subjects were simply asked "on the street" to spontaneously name three countries, flowers and animals. The results showed no statistically significant differences in frequency of hits for the three categories for the three groups. However, the highest hit rate was for the patient group who had heard the words during surgery (35% hits), with no difference between the other two groups (29% hits). The finding of no difference between the groups is discussed in the context of methodological issues when studying memory in anesthesia. It is, furthermore, argued that a healthy nonanesthesized control group is necessary when comparing hit rates between various anesthesized patient groups.
