Comparing Direct (Explicit) and Indirect (Implicit) Measures to Study Unconscious Memory

Comparisons of the relative sensitivity of direct and indirect tasks can provide definitive evidence for unconscious memory when the direct and indirect tasks are matched on all characteristics except instructions. To demonstrate unconscious memory in normal adults, subjects first viewed pairs of words and named one cued word in each pair. During the subsequent assessment of memory, new words and either previously cued words (Experiment 1) or previously uncued words (Experiments 2A and 2B) were presented against a background mask. The subjects judged whether a word was old or new (direct task) or whether the contrast between a word and the mask was high or low (indirect task). For cued words, the direct task was more sensitive than the indirect task. However, for uncued words, the indirect task was initially more sensitive than the direct task, even though the direct task exhibited hypermnesia so that it became more sensitive than the indirect task across trial blocks. The greater initial sensitivity of the indirect task implicates unconscious processes underlying memory for the uncued words. These results indicate that unconscious processes in normal adults can be revealed through comparisons of comparable direct and indirect measures.

[1]  L. Jacoby,et al.  On the relationship between autobiographical memory and perceptual learning. , 1981, Journal of experimental psychology. General.

[2]  G. Mandler,et al.  Activation makes words more accessible, but not necessarily more retrievable. , 1984 .

[3]  J M VANDERPLAS,et al.  The association value of random shapes. , 1959, Journal of experimental psychology.

[4]  Larry L. Jacoby,et al.  The construction of subjective experience: Memory attributions , 1990 .

[5]  J. G. Snodgrass,et al.  Pragmatics of measuring recognition memory: applications to dementia and amnesia. , 1988, Journal of experimental psychology. General.

[6]  Robert A. Bjork,et al.  Measures of Memory , 1988 .

[7]  E. Reingold,et al.  Theory and measurement in the study of unconscious processes , 1990 .

[8]  H. Kucera,et al.  Computational analysis of present-day American English , 1967 .

[9]  D. Schacter,et al.  Intention, awareness, and implicit memory: The retrieval intentionality criterion , 1989 .

[10]  E. Reingold,et al.  Using direct and indirect measures to study perception without awareness , 1988, Perception & psychophysics.

[11]  M. Erdelyi,et al.  Experimental indeterminacies in the dissociation paradigm of subliminal perception , 1986, Behavioral and Brain Sciences.

[12]  N. Brody,et al.  Critical importance of exposure duration for affective discrimination of stimuli that are not recognized. , 1984, Journal of experimental psychology. Learning, memory, and cognition.

[13]  D. Schacter.  Implicit memory: History and current status. , 1987 .

[14]  Daniel L. Schacter,et al.  On the relation between memory and consciousness: Dissociable interactions and conscious experience. , 1989 .

[15]  S. Lewandowsky,et al.  Implicit Memory: Theoretical Issues , 1989 .

[16]  George Mandler,et al.  Nonspecific Effects of Exposure on Stimuli That Cannot Be Recognized , 1987 .

[17]  Robert F. Bornstein,et al.  The Generalizability of Subliminal Mere Exposure Effects: Influence of Stimuli Perceived Without Awareness on Social Behavior , 1987 .

[18]  G. Bonanno,et al.  Preference, familiarity, and recognition after repeated brief exposures to random geometric shapes. , 1986, The American journal of psychology.

[19]  E. Eich,et al.  Memory for unattended events: Remembering with and without awareness , 1984, Memory & cognition.

[20]  J. Kihlstrom.  The cognitive unconscious. , 1987, Science.

[21]  L. Jacoby,et al.  Becoming famous without being recognized: Unconscious influences of memory produced by dividing attention , 1989 .

[22]  R. Zajonc,et al.  Affective discrimination of stimuli that cannot be recognized. , 1980, Science.

[23]  Kim Kirsner,et al.  Implicit memory: Task or process , 1989 .

[24]  D. L. Hintzman.  Human learning and memory: connections and dissociations. , 1990, Annual review of psychology.

[25]  D. Schacter,et al.  Implicit and explicit memory for new associations in normal and amnesic subjects. , 1985, Journal of experimental psychology. Learning, memory, and cognition.

[26]  E. Tulving.  How many memory systems are there , 1985 .

[27]  Marcia K. Johnson,et al.  Human learning and memory. , 1987, Annual review of psychology.

[28]  L. Jacoby,et al.  Memory influences subjective experience: Noise judgments. , 1988 .