Motivation enhances visual working memory capacity through the modulation of central cognitive processes.

Motivation is well known to enhance working memory (WM) capacity, but the mechanism underlying this effect remains unclear. The WM process can be divided into encoding, maintenance, and retrieval, and in a change detection visual WM paradigm, the encoding and retrieval processes can be subdivided into perceptual and central processing. To clarify which of these segments are most influenced by motivation, we measured ERPs in a change detection task with differential monetary rewards. The results showed that the enhancement of WM capacity under high motivation was accompanied by modulations of late central components but not those reflecting attentional control on perceptual inputs across all stages of WM. We conclude that the "state-dependent" shift of motivation impacted the central, rather than the perceptual functions in order to achieve better behavioral performances.

[1]  G. Woodman,et al.  The comparison of visual working memory representations with perceptual inputs. , 2009, Journal of experimental psychology. Human perception and performance.

[2]  E. Vogel,et al.  Sensory gain control (amplification) as a mechanism of selective attention: electrophysiological and neuroimaging evidence. , 1998, Philosophical transactions of the Royal Society of London. Series B, Biological sciences.

[3]  R. Marois,et al.  Posterior parietal cortex activity predicts individual differences in visual short-term memory capacity , 2005, Cognitive, affective & behavioral neuroscience.

[4]  A. Song,et al.  The involvement of the dopaminergic midbrain and cortico-striatal-thalamic circuits in the integration of reward prospect and attentional task demands. , 2012, Cerebral cortex.

[5]  E. Donchin.  Presidential address, 1980. Surprise!...Surprise? , 1981, Psychophysiology.

[6]  Frédéric Gosselin,et al.  On the representation of words and nonwords in visual short-term memory: evidence from human electrophysiology. , 2009, Psychophysiology.

[7]  Maro G. Machizawa,et al.  Electrophysiological Measures of Maintaining Representations in Visual Working Memory , 2007, Cortex.

[8]  Edward K. Vogel,et al.  The capacity of visual working memory for features and conjunctions , 1997, Nature.

[9]  Benoit Brisson,et al.  Dissociation of the N2pc and sustained posterior contralateral negativity in a choice response task , 2008, Brain Research.

[10]  Edward Awh,et al.  The bouncer in the brain , 2008, Nature Neuroscience.

[11]  J B Poline,et al.  The neural system that bridges reward and cognition in humans: An fMRI study , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[12]  Daniel C. Krawczyk,et al.  Reward modulation of prefrontal and visual association cortex during an incentive working memory task , 2007, Brain Research.

[13]  Piotr Bogorodzki,et al.  The effect of motivation on working memory: An fMRI and SEM study , 2008, Neurobiology of Learning and Memory.

[14]  E. Vogel,et al.  Electrophysiological Evidence for a Postperceptual Locus of Suppression during the Attentional Blink Time-based Attention and the Attentional Blink , 1998 .

[15]  Richard L. Lewis,et al.  The mind and brain of short-term memory. , 2008, Annual review of psychology.

[16]  Maro G. Machizawa,et al.  Neural measures reveal individual differences in controlling access to working memory , 2005, Nature.

[17]  M. Chun.  Visual working memory as visual attention sustained internally over time , 2011, Neuropsychologia.

[18]  Julie A Fiez,et al.  Integrating rewards and cognition in the frontal cortex , 2004, Cognitive, affective & behavioral neuroscience.

[19]  E. Vogel,et al.  Contralateral delay activity provides a neural measure of the number of representations in visual working memory. , 2010, Journal of neurophysiology.

[20]  Nicolas Robitaille,et al.  Distinguishing between lateralized and nonlateralized brain activity associated with visual short-term memory: fMRI, MEG, and EEG evidence from the same observers , 2010, NeuroImage.

[21]  M. Shadlen,et al.  Effect of Expected Reward Magnitude on the Response of Neurons in the Dorsolateral Prefrontal Cortex of the Macaque , 1999, Neuron.

[22]  E. Rolls,et al.  The functional neuroanatomy of the human orbitofrontal cortex: evidence from neuroimaging and neuropsychology , 2004, Progress in Neurobiology.

[23]  E. Miller,et al.  Neuronal activity in primate dorsolateral and orbital prefrontal cortex during performance of a reward preference task , 2003, The European journal of neuroscience.

[24]  Wolfram Schultz,et al.  Behavioral reactions reflecting differential reward expectations in monkeys , 2001, Experimental Brain Research.

[25]  K. Hikosaka,et al.  Delay activity of orbital and lateral prefrontal neurons of the monkey varying with different rewards. , 2000, Cerebral cortex.

[26]  Maro G. Machizawa,et al.  Neural activity predicts individual differences in visual working memory capacity , 2004, Nature.

[27]  J. Jay Todd,et al.  Capacity limit of visual short-term memory in human posterior parietal cortex , 2004, Nature.

[28]  Jeff Miller,et al.  Measurement of ERP latency differences: a comparison of single-participant and jackknife-based scoring methods. , 2008, Psychophysiology.

[29]  Edward Awh,et al.  The Role of Spatial Selective Attention in Working Memory for Locations: Evidence from Event-Related Potentials , 2000, Journal of Cognitive Neuroscience.

[30]  S. Luck.  An Introduction to the Event-Related Potential Technique , 2005 .

[31]  P. Goldman-Rakic.  Cellular basis of working memory , 1995, Neuron.

[32]  Carlo Umiltà,et al.  Attentional selection and identification of visual objects are reflected by distinct electrophysiological responses , 2007, Experimental Brain Research.

[33]  L. Pessoa.  How do emotion and motivation direct executive control? , 2009, Trends in Cognitive Sciences.