Semantic elaboration in auditory and visual spatial memory

Abstract

The aim of this study was to investigate the hypothesis that semantic information facilitates auditory and visual spatial learning and memory. An auditory spatial task was administered, whereby healthy participants were placed in the center of a semi-circle that contained an array of speakers where the locations of nameable and non-nameable sounds were learned. In the visual spatial task, locations of pictures of abstract art intermixed with nameable objects were learned by presenting these items in specific locations on a computer screen. Participants took part in both the auditory and visual spatial tasks, which were counterbalanced for order and were learned at the same rate. Results showed that learning and memory for the spatial locations of nameable sounds and pictures was significantly better than for non-nameable stimuli. Interestingly, there was a cross-modal learning effect such that the auditory task facilitated learning of the visual task and vice versa. In conclusion, our results support the hypotheses that the semantic representation of items, as well as the presentation of items in different modalities, facilitate spatial learning and memory.

Keywords: audition; cognitive map; hippocampus; spatial memory; vision.

Figure 1

Auditory spatial memory task: setting and procedure. Top view of the auditory spatial memory array. Thirteen speakers were placed at regular intervals along the semi-circular array. Semantic and non-semantic sounds were presented for 1 s in randomized order at a 1-s ISI.

Figure 2

Visual spatial memory task: setting and procedures. Examples of stimuli used in the visual spatial memory experiment. Each slide shown here was presented individually during the encoding phase.

Figure 3

Semantic vs. non-semantic learning effects. (A,C) Trials to criterion for spatial recall of non-semantically meaningful and semantically meaningful stimuli. The non-semantic stimuli required significantly more trials to reach criterion in both sessions than the semantic stimuli in the auditory and visual tasks. There was a tendency toward significance for performance to be better in Session 2 than in Session 1 in the auditory task, and this effect was significant in the visual task. (B,D) Mean number of correct items recalled on trial 3 (T3) of the spatial memory task for non-semantic and semantic stimuli. More semantic stimuli than non-semantic stimuli were correctly recalled in both sessions in the auditory and visual modalities. This effect was generally significant, and approached significance in Session 2 of the auditory task. Performance was significantly better in Session 2 than 1 in both modalities. *p < 0.05, **p < 0.01, ***p < 0.001, ^♦p < 0.1. The bars show the SEM.

Figure 4

Cross-modal learning effects. (A,B) Comparison of scores between participants who performed the auditory task first and participants who performed the auditory task second, i.e., after the visual task. There is a tendency toward significance for the performance to be different in Session 1 between the two groups for the non-semantic stimuli. A cross-modal learning effect is apparent: the participants who performed the auditory task second performed better on the auditory task. (C,D) Comparison of scores between participants who performed the visual task first and participants who performed the visual task second, i.e., after the auditory task. There is a significant difference in Session 1 performance on non-semantic stimuli between the two groups. There is also a difference in performance related to semantic stimuli in Session 1 and non-semantic stimuli in Session 2, and this approached significance. A cross-modal learning effect is apparent: the participants who performed the visual task second performed better on the visual task. NS, non-semantically meaningful stimuli; S, semantically meaningful stimuli; ***p < 0.001, ^♦p < 0.1. The bars show the SEM.