Encoding and representation of simultaneous and sequential arrays in visuospatial working memory.

Colorado State University, Fort Collins, CO, USA.
Quarterly journal of experimental psychology (2006) (Impact Factor: 1.82). 03/2010; 63(5):856-62. DOI: 10.1080/17470211003690680
Source: PubMed

ABSTRACT The effect of presentation type on organization in visuospatial working memory (VSWM) was examined. Stimuli were presented sequentially or simultaneously at study, and participants made same/different judgements at test. The test array varied in four different spatial configuration conditions: one featuring no changes from study, one in which two items switched, one in which the same array repeated but in a different location, and one in which a completely novel test stimulus appeared. Results indicated the use of a global configuration for both simultaneous and sequential presentations and showed increased impairment of item-level knowledge with sequential presentations. Overall, these results support the use of a global configuration organization as a fundamental aspect of VSWM processing.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In everyday life, the brain is bombarded with a multitude of concurrent and competing stimuli. Only some of these enter consciousness and memory. Attention selects relevant signals for in-depth processing depending on current goals, but also on the intrinsic properties of stimuli. We combined behavior, computational modeling, and functional imaging to investigate mechanisms supporting access to memory based on intrinsic sensory properties. During fMRI scanning, human subjects were presented with pictures of naturalistic scenes that entailed high levels of competition between possible target objects. Following a retention interval of 8 s, participants judged the location (same/different) of a target object extracted from the initial scene. We found that memory performance at retrieval increased with increasing object salience at encoding, indicating a "prior entry" for salient information. fMRI analyses revealed encoding-related activation in the posterior parietal cortex, selectively for salient objects that were later remembered. Moreover, parietal cortex showed increased functional coupling with the medial-temporal lobe, for remembered objects only. These findings reveal a parietotemporal circuit that integrates available sensory cues (based on attention-grabbing saliency signals) and current memory requirements (storing objects' locations) to encode object-related spatial information in working memory.
    Journal of Neuroscience 02/2013; 33(9):4110-7. · 6.91 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The present four experiments examined the effects of pointing movements towards the target locations in a modified free recall task. Three factors were manipulated: the order of the move/no-move trials (blocked or mixed), the type of stimuli presentation (simultaneous or sequential) and the size of the to-be-recalled configurations (7-9 and 5-7 items). Results showed that pointing significantly decreased visuospatial performance both with a mixed and a blocked design. However, in the blocked condition the interference effect of pointing was load-dependent (being inversely related to array size) and occurred only when participants pointed to all stimuli in the first block. Post hoc analyses supported the conclusion that pointing movements interfered with the on-line development of appropriate retrieval strategies, like parsing the configurations into smaller chunks or creating global visual images.
    Psychological Research 11/2011; 76(6):699-712. · 2.47 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The role of vision in the construction of spatial representations has been the object of numerous studies and heated debate. The core question of whether visual experience is necessary to form spatial representations has found different, often contradictory answers. The present paper examines mental images generated from verbal descriptions of spatial environments. Previous evidence had shown that blind individuals have difficulty remembering information about spatial environments. By testing a group of congenitally blind people, we replicated this result and found that it is also present when the overall mental model of the environment is assessed. This was not always the case, however, but appeared to correlate with some blind participants' lower use of a mental imagery strategy and preference for a verbal rehearsal strategy, which was adopted particularly by blind people with more limited mobility skills. The more independent blind people who used a mental imagery strategy performed as well as sighted participants, suggesting that the difficulty blind people may have in processing spatial descriptions is not due to the absence of vision per se, but could be the consequence of both, their using less efficient verbal strategies and having poor mobility skills.
    Acta psychologica 12/2012; 142(1):43-50. · 2.19 Impact Factor

Full-text (2 Sources)

Available from
May 20, 2014