The Case Against Specialized Visual-Spatial Short-Term Memory

    loading  Checking for direct PDF access through Ovid


The dominant paradigm for understanding working memory, or the combination of the perceptual, attentional, and mnemonic processes needed for thinking, subdivides short-term memory (STM) according to whether memoranda are encoded in aural-verbal or visual formats. This traditional dissociation has been supported by examples of neuropsychological patients who seem to selectively lack STM for either aural-verbal, visual, or spatial memoranda, and by experimental research using dual-task methods. Though this evidence is the foundation of assumptions of modular STM systems, the case it makes for a specialized visual STM system is surprisingly weak. I identify the key evidence supporting a distinct verbal STM system—patients with apparent selective damage to verbal STM and the resilience of verbal short-term memories to general dual-task interference—and apply these benchmarks to neuropsychological and experimental investigations of visual-spatial STM. Contrary to the evidence on verbal STM, patients with apparent visual or spatial STM deficits tend to experience a wide range of additional deficits, making it difficult to conclude that a distinct short-term store was damaged. Consistently with this, a meta-analysis of dual-task visual-spatial STM research shows that robust dual-task costs are consistently observed regardless of the domain or sensory code of the secondary task. Together, this evidence suggests that positing a specialized visual STM system is not necessary.

    loading  Loading Related Articles