Memory Processes Involved in Morning Recall of Mental Rem-Sleep Experience: A Psycholinguistic Study
For two nights 10 subjects were asked to recall their mental sleep experience after experimental awakening during REM sleep (night report) and again upon spontaneous morning awakening (morning report). The two types of report were subjected to linguistic analysis and compared. The number of sentences used to describe the mental sleep experience, their syntactic structures, and over-all report length were similar. Those contents common to both reports were in both cases encoded in about one fourth of the sleep-related kernel sentences, these kernel sentences being distributed over about two-thirds of the sentences of the report, generally the longer ones. The organization of the morning reports reflects the consolidation of the contents in memory. The only significant physiological variable, waking time, was negatively correlated to the numbers of kernel sentences and sentences reproducing contents previously encoded in the night reports. The organization of the morning report primarily appears to be the result of retrieval and encoding procedures relative to the mental sleep experience preceding the night awakening rather than simply to the encoded contents of the night report.