The role of evaluatively conditioned stimuli in iconic memory

Abstract

In the present study, an attempt was made to replicate results found about the influence of valence on prioritisation and decay in iconic memory. Hereby, the evaluative conditioning effect was used to induce valence for formerly neutral stimuli. The effect is gained by pairing neutral stimuli with either positive, negative, or neutral images in a conditioning phase. Afterwards, the conditioned stimuli acted as targets in an iconic memory test. In the iconic memory test, targets were presented together with seven other stimuli on a circular placement on the screen for a short time. A cue delayed by either 17, 68, 221, 493, or 1003 ms pointed at the target to be reported. Participants rated the targets before and after the conditioning phase. In addition, the affective and neutral images used in the pairing procedure were rated at the end of the experiment. While no significant change in rating could be observed for the conditioned targets, a significant effect of conditioned valence was still present in the response times and the accuracy of the iconic memory test. Participants reacted the quickest in response to a cue for positively conditioned targets compared to neutral or negatively conditioned targets. Accuracy was highest for positively conditioned targets and was lowest for negatively conditioned targets. Unlike in prior studies, slower decay of information in iconic memory for negative targets was not revealed. Further research should be conducted to identify reasons for this inconsistency.

Keywords: Evaluative conditioning; Iconic memory; Valence; Visual processing.

Fig. 1

Schematic illustration of a trial of the iconic memory task Note. Example of a trial with the CSs as targets

Fig. 2

Schematic illustration of a trial of the evaluative conditioning phase Note. The image representing the US in this figure was not used in the experiment

Fig. 3

Average evaluative ratings of the different CSs in the pre- and post-rating phases Note. Average CS ratings for each valence level before (pre) and after (post) the evaluative conditioning phase across both groups. The rating scale ranged from 1 to 21. Error bars show the standard errors of the mean

Fig. 4

Average response times to targets of different conditioned valence in the iconic memory post-test Note. Average response time for each valence level in the iconic memory post-test. Only trials with correct responses are included. Error bars show the standard errors of the mean

Fig. 5

Average recognition accuracy in the iconic memory post-test as a function of the conditioned valence of the target Note. Average accuracy in response to CSs of each valence level in the iconic memory post-test as a function of cue-delay between target and cue arrow. Solid lines show fitted decay functions on accuracy. Error bars indicate the standard errors of the mean. The dotted line represents the chance level

Fig. 6

Parameter estimates Note. Parameter estimates of the decay function on aggregated accuracy for each valence level in the iconic memory post-test. Initial availability is represented by α; β represents the amount of information transferred to visual short-term memory for further processing, and τ indicates the duration of information in iconic memory