Common neural mechanisms supporting spatial working memory, attention and motor intention - PubMed (original) (raw)

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Common neural mechanisms supporting spatial working memory, attention and motor intention

Akiko Ikkai et al. Neuropsychologia. 2011 May.

Abstract

The prefrontal cortex (PFC) and posterior parietal cortex (PPC) are critical neural substrates for working memory. Neural activity persists in these regions during the maintenance of a working memory representation. Persistent activity, therefore, may be the neural mechanism by which information is temporarily maintained. However, the nature of the representation or what is actually being represented by this persistent activity is not well understood. In this review, we summarize the recent functional magnetic resonance imaging (fMRI) studies conducted in our laboratory that test hypotheses about the nature of persistent activity during a variety of spatial cognition tasks. We find that the same areas in the PFC and PPC that show persistent activity during the maintenance of a working memory representation also show persistent activity during the maintenance of spatial attention and the maintenance of motor intention. Therefore, we conclude that persistent activity is not specific to working memory, but instead, carries information that can be used generally to support a variety of cognitions. Specifically, activity in topographically organized maps of prioritized space in PFC and PPC could be read out to guide attention allocation, spatial memory, and motor planning.

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Figures

Fig 1

Fig 1

a. Trial schematic of a memory guided saccade (MGS) task. A subject must maintain the location of a briefly presented visual cue over a memory delay and then make a saccade to the past cue's location. b. A spike histogram from a neuron in the monkey PFC during a MGS task (Funahashi et al., 1989). c. BOLD signal time course from the human PFC during a MGS task (Srimal & Curtis, 2008). Notice that in both species neural activity persists during the memory delay period. C=cue, D=delay, and R=response.

Fig 2

Fig 2

Task and results summary from working memory (WM), attention, and intention studies. Trial schematics are shown for each task (a., d., and g.). Statistical parametric maps of significant delay period specific activity are projected onto the surface of a subject's cortical sheet for each task (b., e., and h.). Time courses (average, SEM) from the PFC (c., f., i. top panels) and PPC (bottom panels) are shown time locked to the presentation of the cue. Solid lines represent trials in which the memoranda (c.), locus of attention (f.), or direction of antisaccade (i.) was in hemifield contralateral to the cortical hemisphere and dashed lines represent ipsilateral trials. Notice that both PFC and PPC show delay period activation, that this activation persists throughout the delay period, and it shows a contralateral bias.

Fig 3

Fig 3

Delay period activity from subjects who participated in all three of the studies. (N=5). a. BOLD time-series from the exact same voxels in superior precentral sulcus (sPCS) across the three studies. Notice that delay period activity persists during the WM, attention, and intention delay periods and shows a contralateral bias. b. Cortex with significant delay period activity projected on an inflated cortical sheet of the right hemisphere. The color wheel is the legend for the delay period activity. Areas that show both activation for attention and intention would be depicted in magenta. Areas that show delay period activation during all three tasks are depicted in black and those areas are labeled.

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References

    1. Andersen RA, Buneo CA. Intentional maps in posterior parietal cortex. Annu Rev Neurosci. 2002;25:189–220. - PubMed
    1. Anton-Erxleben K, Stephan VM, Treue S. Attention reshapes center-surround receptive field structure in macaque cortical area MT. Cereb Cortex. 2009;19(10):2466–2478. - PMC - PubMed
    1. Armstrong KM, Chang MH, Moore T. Selection and maintenance of spatial information by frontal eye field neurons. J Neurosci. 2009;29(50):15621–15629. - PMC - PubMed
    1. Armstrong KM, Moore T. Rapid enhancement of visual cortical response discriminability by microstimulation of the frontal eye field. Proc Natl Acad Sci U S A. 2007;104(22):9499–9504. - PMC - PubMed
    1. Averbeck BB, Seo M. The statistical neuroanatomy of frontal networks in the macaque. PLoS Comput Biol. 2008;4(4):e1000050. - PMC - PubMed

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