Figure 1.
Experiment 1: Mean (± SEM) short-term memory accuracy among sensory modalities for simple, artificial stimuli.
Short-term retention of auditory stimuli declines at a greater rate than retention of visual or tactile stimuli. There were no differences in accuracy among the sensory modalities for trials with brief retention intervals (1–4 s), indicating that the initial discriminability of the stimuli was approximately equal. However, at longer retention intervals (8–32 s), accuracy for auditory trials was significantly lower than visual and tactile trials. Post-hoc tests (p<.05, Bonferroni correction for multiple comparisons): *Accuracy in the auditory block significantly lower than the tactile block. †Accuracy in the auditory block significantly lower than the visual block.
Figure 2.
Experiment 2: Mean (+ SEM) recognition accuracy among sensory modalities for complex, naturalistic stimuli.
(A) When tested immediately after the study phase, recognition accuracy was lower for auditory stimuli than visual or tactile stimuli. (B) Similarly, recognition was lower for auditory stimuli when tested 24 hours after the study phase. (C) When tested one week after the study phase, recognition accuracy was significantly lower for auditory stimuli than tactile stimuli, but the difference between auditory and visual recognition was not significant. Post-hoc tests (p<.05; Bonferroni correction): *Accuracy in the auditory block significantly lower than the tactile block. †Accuracy in the auditory block significantly lower than the visual block.
Figure 3.
Comparison of visual and auditory short-term memory among primates.
(A) In the present experiment, inferior retention was observed for auditory compared to visual stimuli in human subjects. This pattern of results is qualitatively similar to that which has been observed in the chimpanzee (B), as well as both old-world (C) and new-world monkeys (D). (B) Adapted from Hashiya and Kojima [12]; (C) adapted from Fritz et al. [6]; (D) adapted from Colombo and D’Amato [1].