Abstract
We assessed visual short-term memory (VSTM) for color in 6- and 8-month-old infants (n = 76) using a one-shot change detection task. In this task, a sample array of two colored squares was visible for 517 ms, followed by a 317-ms retention period and then a 3000-ms test array consisting of one unchanged item and one item in a new color. We tracked gaze at 60 Hz while infants looked at the changed and unchanged items during test. When the two sample items were different colors (Experiment 1), 8-month-old infants exhibited a preference for the changed item, indicating memory for the colors, but 6-month-olds exhibited no evidence of memory. When the two sample items were the same color and did not need to be encoded as separate objects (Experiment 2), 6-month-old infants demonstrated memory. These results show that infants can encode information in VSTM in a single, brief exposure that simulates the timing of a single fixation period in natural scene viewing, and they reveal rapid developmental changes between 6 and 8 months in the ability to store individuated items in VSTM.
Highlights
Visual short-term memory (VSTM) is critically important for normal processing of the visual world
The failure of the 6-month-old infants in Experiment 1 was not, the result of a general inability to demonstrate a novelty preference in this task. Their failure was a result of the fact that two different colors were presented in the sample array and had to be individuated in VSTM
Infants’ response to the change in the multipleitem test array was slower and less robust than was the response of 8-month-old infants in Experiment 1, despite the fact that the encoding portion of the task was simplified. This may indicate that the 6-month-old infants had some difficulty individuating the two colored squares in the test array
Summary
Visual short-term memory (VSTM) is critically important for normal processing of the visual world. Adults use it thousands of times each day to perceive continuity across eye blinks and eye movements (Irwin, 1991; Hollingworth and Henderson, 2002), and to compare visual objects that cannot be simultaneously foveated (Pomplun et al, 2001) In this memory system, representations are rapidly formed in an all-or-none manner (50 ms per object: Vogel et al, 2006; Zhang and Luck, 2009), capacity is extremely limited, and the information is maintained only briefly, until it is replaced with new information. To isolate VSTM, research with adult participants has used change detection tasks with very brief encoding and retention periods (e.g., several 100 ms) (Luck and Vogel, 1997) In this one-shot change detection task, memory is assessed after a single stimulus cycle (a single “shot”). The timing is designed to reflect natural vision, in which a brief period of fixation is followed by a short gap (reflecting the suppression of vision during a saccade or eyeblink) and another period of fixation
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
