The Dynamic Processing Model of Working Memory

Recent shifts in the understanding of how the mind and brain retain information in working memory (WM) call for revision to traditional theories. Evidence for the existence of dynamic, “activity-silent” short-term retention processes in the brain diverge from conventional models that have argued that information is always retained in WM by sustained neural activity in buffers. Such evidence comes from the use of machine-learning analytic approaches to decode patterns of brain activity and the simultaneous administration of transcranial magnetic stimulation (TMS) to causally manipulate brain activity in specific areas and time-points. TMS has been used to 'ping' brain areas and reactivate latent representations retained in WM and affect memory performance. These findings argue for a supplement to the sustained retention mechanisms associated with attending to information in WM. Moreover, brain decoding methods reveal that dynamic levels of representational codes are retained in WM, which vary according to task context, from perceptual/sensory codes in posterior areas to more abstract, recoded representations distributed across frontal-parietal regions. A Dynamic Processing Model of WM is advanced to account for the overall pattern of results. Keywords: activity-silent, short-term memory, working memory, sensory-motor recruitment