Date of Award
Master of Arts
Aaron T. Buss
Caglar Tas, Shannon Ross-Sheehy
Visual working memory (VWM) allows us to hold visual information in mind to be manipulated for a task. Previous research shows that performance varies based on factors such as stimulus modality and number of distractors. This study aimed to explore the effect of response type on VWM performance in 4.5- and 5.5-year-olds. A single-item probe color change detection task and a cued recall with labeling task were administered. The tasks were identical in structure until the response phase of the trial. Neural data were collected using functional near-infrared spectroscopy. Both tasks used set-sizes 1-3 and six canonical colors (red, orange, yellow, green, blue, purple). All children were given the change detection task first. Behavioral analyses show a main effect of set size for both the change detection task, F(2, 618) = 85.37, p < .001, and the cued recall task, F(2, 711) = 131.19, p < .001, with a significant decrease in performance as set size increased. Moreover, VWM capacity was estimated to be higher in the change detection task (k4=2.12, k5=2.36) compared to the cued recall task (k4=1.18, k5=1.84) (p < .001). When we look at the neural data, both tasks activated bilateral temporal and parietal cortices. Comparing same and different response in the change detection task, we saw a distinct network of activation for both in the 5-year-old group but not the 4-year-old group, suggesting a developmental shift in neural activity. The cued recall task elicited decreased activation patterns in the 5-year-old group in frontal and temporal regions which suggest a need for a greater amount of neural resources due to greater difficulty in the younger age group.
Eddings, Rachel, "Exploring the Effects of Response Type in a Visual Working Memory Task: An fNIRS Study. " Master's Thesis, University of Tennessee, 2020.