Effects of Color and Luminance Contrast on Size Perception-Evidence from a Horizontal Parallel Lines Illusion

Increasing perceptual separateness affects working memory for depth - re-allocation of attention from boundaries to the fixated center

For decades, working memory (WM) has been a heated research topic in the field of cognitive psychology. However, most studies on WM presented visual stimuli on a two-dimensional plane, rarely involving depth perception. Several previous studies have investigated how depth information is stored in WM, and found that WM for depth is even more limited in capacity and the memory performance is poor compared to visual WM. In the present study, we used a change detection task to investigate whether dissociating memory items by different visual features, thereby to increase their perceptual separateness, can improve WM performance for depth. Memory items presented at various depth planes were bound with different colors (Experiments 1 and 3) or sizes (Experiment 2). The memory performance for depth locations of visual stimuli with homogeneous and heterogeneous appearances were tested and compared. The results showed a consistent pattern that although separating items with various feature values did not affect the overall memory performance, the manipulation significantly improved memory performance for the middle depth locations but impaired the performance for the boundary locations when observers fixated at the center of the whole depth volume. The memory benefits of feature separation can be attributed to enhanced individuation of memory items, therefore facilitating a more balanced allocation of attention and memory resources.

The Size-Value Compatibility Effect

This study aimed to examine the relationship between an object's physical size and judgements of its value. Two preregistered experiments were performed to explore a size-value compatibility effect. Two images of Japanese-yen coins with different values but similar actual sizes (10-yen and 100-yen) were manipulated for size and presented side-by-side on a computer screen. Participants judged which coin was larger or smaller based on the images. Results revealed that size judgements were slower and less accurate when the lower-value coin was presented as larger than the higher-value coin, compared to when the lower-value coin was presented as smaller. This effect was observed even after participants had been allowed to examine the physical coins prior to the experiment to judge their actual size. This finding suggests that participants perceived the coins' values based on their sizes, indicating it may be difficult for many people to stop thinking 'better is bigger'.