Domain-dependent activation during spatial and nonspatial auditory working memory

Abstract

Visual system has been proposed to be divided into two, the ventral and dorsal, processing streams. The ventral pathway is thought to be involved in object identification whereas the dorsal pathway processes information regarding the spatial locations of objects and the spatial relationships among objects. Several studies on working memory (WM) processing have further suggested that there is a dissociable domain-dependent functional organization within the prefrontal cortex for processing of spatial and nonspatial visual information. Also the auditory system is proposed to be organized into two domain-specific processing streams, similar to that seen in the visual system. Recent studies on auditory WM have further suggested that maintenance of nonspatial and spatial auditory information activates a distributed neural network including temporal, parietal, and frontal regions but the magnitude of activation within these activated areas shows a different functional topography depending on the type of information being maintained. The dorsal prefrontal cortex, specifically an area of the superior frontal sulcus (SFS), has been shown to exhibit greater activity for spatial than for nonspatial auditory tasks. Conversely, ventral frontal regions have been shown to be more recruited by nonspatial than by spatial auditory tasks. It has also been shown that the magnitude of this dissociation is dependent on the cognitive operations required during WM processing. Moreover, there is evidence that within the nonspatial domain in the ventral prefrontal cortex, there is an across-modality dissociation during maintenance of visual and auditory information. Taken together, human neuroimaging results on both visual and auditory sensory systems support the idea that the prefrontal cortex is organized according to the type of information being maintained in WM.

The impact of auditory working memory training on the fronto-parietal working memory network

“…Consistent with a number of studies mentioned above, we assume that within the prefrontal cortex, there exists a relative specialization for auditory object working memory with the ventrolateral prefrontal cortex being involved in auditory working memory tasks (for a review see also Rämä, 2008). Thus, this region might be recruited for maintaining and rehearsing auditory material over short periods of time.…”

Modelling neural correlates of working memory: A coordinate-based meta-analysis

“…Many concepts have stressed a distinction between the ventral and dorsal aspects of the human LPFC in working memory, though different hypotheses on the nature of their functional segregation exist (Curtis & D’Esposito 2004). One view relates this specialization to the processing of spatial and non-spatial, i.e., object related, information (Romanski 2004, Rämä 2008). Other authors, however, have argued, that dorsal and ventral prefrontal cortices perform qualitatively different operations such as individual item processing vs. the organization of multiple pieces of information (Müller & Knight 2006; Blumenfeld & Ranganath 2007).…”

Visual and spatial working memory: From boxes to networks

“…A comparable result was observed by Saults and Cowan (2007) who attributed the equal performances to central capacity (for the moment we ignore the modality-specific effects). Similarly, in an fMRI study, Arnott et al (2005) observed activations in the parietal cortex if locations of sounds had to be memorized similar to those found for visual objects but anterior temporal activations if the sound pattern was relevant (Altmann et al, 2007; see also Rä mä , 2008).…”