Positive affect versus reward: emotional and motivational influences on cognitive control

Kimberly S Chiew, Todd S Braver, Kimberly S Chiew, Todd S Braver

Abstract

It is becoming increasingly appreciated that affective influences can contribute strongly to goal-oriented cognition and behavior. However, much work is still needed to properly characterize these influences and the mechanisms by which they contribute to cognitive processing. An important question concerns the nature of emotional manipulations (i.e., direct induction of affectively valenced subjective experience) versus motivational manipulations (e.g., delivery of performance-contingent rewards and punishments) and their impact on cognitive control. Empirical evidence suggests that both kinds of manipulations can influence cognitive control in a systematic fashion, but investigations of both have largely been conducted independently of one another. Likewise, some theoretical accounts suggest that emotion and motivation may modulate cognitive control via common neural mechanisms, while others suggest the possibility of dissociable influences. Here, we provide an analysis and synthesis of these various accounts, suggesting potentially fruitful new research directions to test competing hypotheses.

Keywords: cognitive control; dopamine; emotion; motivation; reward.

References

    1. Aarts H., Custers R., Marien H. (2008a). Preparing and motivating behavior outside of awareness. Science 319, 1639.10.1126/science.1150432
    1. Aarts H., Custers R., Veltkamp M. (2008b). Goal priming and the affective-motivational route to nonconscious goal pursuit. Soc. Cogn. 26, 555–57710.1521/soco.2008.26.5.555
    1. Arias-Carrion O., Poppel E. (2007). Dopamine, learning, and reward-seeking behavior. Acta Neurobiol. Exp. (Wars) 67, 481–488
    1. Arnsten A. F., Cai J. X., Murphy B. L., Goldman-Rakic P. S. (1994). Dopamine d1 receptor mechanisms in the cognitive performance of young adult and aged monkeys. Psychopharmacology (Berl.) 116, 143–15110.1007/BF02245056
    1. Ashby F. G., Isen A. M., Turken A. U. (1999). A neuropsychological theory of positive affect and its influence on cognition. Psychol. Rev. 106, 529–55010.1037/0033-295X.106.3.529
    1. Ashby F. G., Valentin V. V., Turken A. U. (2002). “The effects of positive affect and arousal on working memory and executive attention,” in Emotional Cognition, eds Moore S., Oaksford M. (Amsterdam/Philadelphia: John Benjamins Publishing Company; ), 245–288
    1. Aston-Jones G., Cohen J. D. (2005). An integrative theory of locus coeruleus-norepinephrine function: adaptive gain and optimal performance. Annu. Rev. Neurosci. 28, 403–45010.1146/annurev.neuro.28.061604.135709
    1. Bargh J. A., Gollwitzer P. M., Lee-Chai A., Barndollar K., Trotschel R. (2001). The automated will: nonconscious activation and pursuit of behavioral goals. J. Pers. Soc. Psychol. 81, 1014–102710.1037/0022-3514.81.6.1014
    1. Barrett L. F., Mesquita B., Ochsner K. N., Gross J. J. (2007). The experience of emotion. Annu. Rev. Psychol. 58, 373–40310.1146/annurev.psych.58.110405.085709
    1. Beatty J. (1982). Task-evoked pupillary responses, processing load, and the structure of processing resources. Psychol. Bull. 91, 276–29210.1037/0033-2909.91.2.276
    1. Beatty J., Lucero-Wagoner B. (2000). “The pupillary system,” in Handbook of Psychophysiology, eds Cacioppo J. T., Tassinary L. G., Berntson G. (Cambridge: Cambridge University Press; ), 142–162
    1. Berridge K. C. (1996). Food reward: brain substrates of wanting and liking. Neurosci. Biobehav. Rev. 20, 1–2510.1016/0149-7634(95)00033-B
    1. Berridge K. C. (2000). Measuring hedonic impact in animals and infants: microstructure of affective taste reactivity patterns. Neurosci. Biobehav. Rev. 24, 173–19810.1016/S0149-7634(99)00072-X
    1. Berridge K. C. (2003). Pleasures of the brain. Brain Cogn. 52, 106–12810.1016/S0278-2626(03)00014-9
    1. Berridge K. C. (2007). The debate over dopamine’s role in reward: the case for incentive salience. Psychopharmacology (Berl.) 191, 391–43110.1007/s00213-006-0578-x
    1. Berridge K. C., Robinson T. E. (1998). What is the role of dopamine in reward: hedonic impact, reward learning, or incentive salience? Brain Res. Brain Res. Rev. 28, 309–36910.1016/S0165-0173(98)00019-8
    1. Berridge K. C., Robinson T. E. (2003). Parsing reward. Trends Neurosci. 26, 507–51310.1016/j.tins.2003.09.001
    1. Berridge K. C., Robinson T. E., Aldridge J. W. (2009). Dissecting components of reward: “liking,” “wanting,” and learning. Curr. Opin. Pharmacol. 9, 65–7310.1016/j.coph.2008.12.014
    1. Bijleveld E., Custers R., Aarts H. (2010). Unconscious reward cues increase invested effort, but do not change speed-accuracy tradeoffs. Cognition 115, 330–33510.1016/j.cognition.2009.12.012
    1. Bradley M. M., Codispoti M., Cuthbert B. N., Lang P. J. (2001). Emotion and motivation i: defensive and appetitive reactions in picture processing. Emotion 1, 276–29810.1037/1528-3542.1.3.300
    1. Bradley M. M., Miccoli L., Escrig M. A., Lang P. J. (2008). The pupil as a measure of emotional arousal and autonomic activation. Psychophysiology 45, 602–60710.1111/j.1469-8986.2008.00654.x
    1. Braver T. S., Barch D. M., Cohen J. D. (2002). “The role of the prefrontal cortex in normal and disordered cognitive control: a cognitive neuroscience perspective,” in Principles of Frontal Lobe Function, eds Stuss D. T., Knight R. T. (Oxford: Oxford University Press; ), 428–447
    1. Braver T. S., Barch D. M., Keys B. A., Carter C. S., Cohen J. D., Kaye J. A., Janowsky J. S., Taylor S. F., Yesavage J. A., Mumenthaler M. S., Jagust W. J., Reed B. R. (2001). Context processing in older adults: evidence for a theory relating cognitive control to neurobiology in healthy aging. J. Exp. Psychol. Gen. 130, 746–76310.1037/0096-3445.130.4.746
    1. Braver T. S., Cohen J. D. (2000). “On the control of control: the role of dopamine in regulating prefrontal function and working memory,” in Attention and Performance XVIII, eds Monsell S., Driver J. (Cambridge, MA: MIT Press; ), 713–737
    1. Braver T. S., Gray J. R., Burgess G. C. (2007). “Explaining the many varieties of working memory variation: dual mechanisms of cognitive control,” in Variation in Working Memory, eds Conway A. R. A., Jarrold C., Kane M. J., Miyake A., Towse J. N. (Oxford: Oxford University Press; ), 76–106
    1. Buck R. (2000). Conceptualizing motivation and emotion. Behav. Brain Sci. 23, 195–19610.1017/S0140525X00262420
    1. Cacioppo J. T., Petty R. E., Losch M. E., Kim H. S. (1986). Electromyographic activity over facial muscle regions can differentiate the valence and intensity of affective reactions. J. Pers. Soc. Psychol. 50, 260–26810.1037/0022-3514.50.2.260
    1. Canli T., Zhao Z., Desmond J. E., Kang E., Gross J., Gabrieli J. D. (2001). An fmri study of personality influences on brain reactivity to emotional stimuli. Behav. Neurosci. 115, 33–4210.1037/0735-7044.115.1.33
    1. Carver C. S. (2003). Pleasure as a sign you can attend to something else: placing positive feelings within a general model of affect. Cogn. Emot. 17, 241–26110.1080/02699930302294
    1. Carver C. S. (2006). Approach, avoidance, and the self-regulation of affect and action. Motiv. Emot. 30, 105–11010.1007/s11031-006-9044-7
    1. Carver C. S., Scheier M. F. (1998). On the Self-Regulation of Behavior. New York: Cambridge University Press
    1. Chatham C. H., Frank M. J., Munakata Y. (2009). Pupillometric and behavioral markers of a developmental shift in the temporal dynamics of cognitive control. Proc. Natl. Acad. Sci. U.S.A. 106, 5529–553310.1073/pnas.0810002106
    1. Cohen J. D., Braver T. S., Brown J. W. (2002). Computational perspectives on dopamine function in prefrontal cortex. Curr. Opin. Neurobiol. 12, 223–22910.1016/S0959-4388(02)00314-8
    1. Cohen J. D., Servan-Schreiber D. (1992). Context, cortex, and dopamine: a connectionist approach to behavior and biology in schizophrenia. Psychol. Rev. 99, 45–7710.1037/0033-295X.99.1.45
    1. Cools R., Sheridan M., Jacobs E., D’Esposito M. (2007). Impulsive personality predicts dopamine-dependent changes in frontostriatal activity during component processes of working memory. J. Neurosci. 27, 5506–551410.1523/JNEUROSCI.0601-07.2007
    1. Custers R., Aarts H. (2010). The unconscious will: how the pursuit of goals operates outside of conscious awareness. Science 329, 47–5010.1126/science.1188595
    1. Davidson R. J. (1992). Anterior cerebral asymmetry and the nature of emotion. Brain Cogn. 20, 125–15110.1016/0278-2626(92)90065-T
    1. Davidson R. J., Ekman P., Saron C. D., Senulis J. A., Friesen W. V. (1990). Approach-withdrawal and cerebral asymmetry: emotional expression and brain physiology. I. J. Pers. Soc. Psychol. 58, 330–34110.1037/0022-3514.58.2.330
    1. Davidson R. J., Irwin W. (1999). The functional neuroanatomy of emotion and affective style. Trends Cogn. Sci. (Regul. Ed.) 3, 11–2110.1016/S1364-6613(98)01265-0
    1. D’Esposito M., Aguirre G. K., Zarahn E., Ballard D., Shin R. K., Lease J. (1998). Functional mri studies of spatial and nonspatial working memory. Brain Res. Cogn. Brain Res. 7, 1–1310.1016/S0926-6410(98)00004-4
    1. Dolan R. J. (2002). Emotion, cognition, and behavior. Science 298, 1191–119410.1126/science.1076358
    1. Dreisbach G. (2006). How positive affect modulates cognitive control: the costs and benefits of reduced maintenance capability. Brain Cogn. 60, 11–1910.1016/j.bandc.2005.08.003
    1. Dreisbach G., Goschke T. (2004). How positive affect modulates cognitive control: reduced perseveration at the cost of increased distractibility. J. Exp. Psychol. Learn Mem. Cogn. 30, 343–35310.1037/0278-7393.30.2.343
    1. Duffy E. (1962). Activation and Behavior. Oxford: Wiley
    1. Durstewitz D., Seamans J. K. (2008). The dual-state theory of prefrontal cortex dopamine function with relevance to catechol-o-methyltransferase genotypes and schizophrenia. Biol. Psychiatry 64, 739–74910.1016/j.biopsych.2008.05.015
    1. Egerton A., Mehta M. A., Montgomery A. J., Lappin J. M., Howes O. D., Reeves S. J., Cunningham V. J., Grasby P. M. (2009). The dopaminergic basis of human behaviors: a review of molecular imaging studies. Neurosci. Biobehav. Rev. 33, 1109–113210.1016/j.neubiorev.2009.05.005
    1. Foote S. L., Aston-Jones G., Bloom F. E. (1980). Impulse activity of locus coeruleus neurons in awake rats and monkeys is a function of sensory stimulation and arousal. Proc. Natl. Acad. Sci. U.S.A. 77, 3033–303710.1073/pnas.77.5.3033
    1. Fredrickson B. L. (2004). The broaden-and-build theory of positive emotions. Philos. Trans. R. Soc. Lond. B Biol. Sci. 359, 1367–137810.1098/rstb.2004.1512
    1. Fredrickson B. L., Branigan C. (2005). Positive emotions broaden the scope of attention and thought-action repertoires. Cogn. Emot. 19, 313–33210.1080/02699930441000238
    1. Gendron M., Barrett L. F. (2009). Reconstructing the past: a century of ideas about emotion in psychology. Emot. Rev. 1, 316–33910.1177/1754073909338877
    1. Gibbs S. E., D’Esposito M. (2006). A functional magnetic resonance imaging study of the effects of pergolide, a dopamine receptor agonist, on component processes of working memory. Neuroscience 139, 359–37110.1016/j.neuroscience.2005.11.055
    1. Gilzenrat M. S., Nieuwenhuis S., Jepma M., Cohen J. D. (2010). Pupil diameter tracks changes in control state predicted by the adaptive gain theory of locus coeruleus function. Cogn. Affect. Behav. Neurosci. 10, 252–26910.3758/CABN.10.2.252
    1. Grace A. A. (1991). Phasic versus tonic dopamine release and the modulation of dopamine system responsivity: a hypothesis for the etiology of schizophrenia. Neuroscience 41, 1–2410.1016/0306-4522(91)90196-U
    1. Granholm E., Asarnow R. F., Sarkin A. J., Dykes K. L. (1996). Pupillary responses index cognitive resource limitations. Psychophysiology 33, 457–46110.1111/j.1469-8986.1996.tb01071.x
    1. Gray J. R. (2001). Emotional modulation of cognitive control: approach-withdrawal states double-dissociate spatial from verbal two-back task performance. J. Exp. Psychol. Gen. 130, 436–45210.1037/0096-3445.130.3.436
    1. Gray J. R., Braver T. S. (2002). “Integration of emotion and cognitive control,” in Emotional Cognition, eds Moore S., Oaksford M. (Amsterdam/Philadelphia: John Benjamins Publishing Company; ), 289–316
    1. Harmon-Jones E. (2003). Early career award. Clarifying the emotive functions of asymmetrical frontal cortical activity. Psychophysiology 40, 838–84810.1111/1469-8986.00121
    1. Harmon-Jones E., Gable P. A. (2009). Neural activity underlying the effect of approach-motivated positive affect on narrowed attention. Psychol. Sci. 20, 406–40910.1111/j.1467-9280.2009.02416.x
    1. Hull C. L. (1952). A Behavior System: An Introduction to Behavior Theory Concerning the Individual Organism. New Haven: Yale University Press
    1. Isen A. M., Daubman K. A. (1984). The influence of affect on categorization. J. Pers. Soc. Psychol. 47, 1206–121710.1037/0022-3514.47.6.1206
    1. Isen A. M., Daubman K. A., Nowicki G. P. (1987). Positive affect facilitates creative problem solving. J. Pers. Soc. Psychol. 52, 1122–113110.1037/0022-3514.52.6.1122
    1. Kimberg D. Y., D’Esposito M., Farah M. J. (1997). Effects of bromocriptine on human subjects depend on working memory capacity. Neuroreport 8, 3581–358510.1097/00001756-199711100-00032
    1. Kouneiher F., Charron S., Koechlin E. (2009). Motivation and cognitive control in the human prefrontal cortex. Nat. Neurosci. 12, 939–94510.1038/nn.2321
    1. Kruglanski A. Y., Shah J. Y., Fishbach A., Friedman R., Chun W. Y. (2002). A theory of goal systems. Adv. Exp. Soc. Psychol. 34, 331–37810.1016/S0065-2601(02)80008-9
    1. Laming D. R. J. (2000). On the behavioural interpretation of neurophysiological observation. Behav. Brain Sci. 23, 209–20910.1017/S0140525X00392421
    1. Lang P. J., Bradley M. M. (2008). “Appetitive and defensive motivation is the substrate of emotion,” in Handbook of Approach and Avoidance Motivation, ed. Elliot A. J. (New York: Psychology Press; ), 51–66
    1. Lang P. J., Bradley M. M., Cuthbert B. N. (1990). Emotion, attention, and the startle reflex. Psychol. Rev. 97, 377–39510.1037/0033-295X.97.3.377
    1. Leon M. I., Shadlen M. N. (1999). Effect of expected reward magnitude on the response of neurons in the dorsolateral prefrontal cortex of the macaque. Neuron 24, 415–42510.1016/S0896-6273(00)80854-5
    1. Locke H. S., Braver T. S. (2008). Motivational influences on cognitive control: behavior, brain activation, and individual differences. Cogn. Affect. Behav. Neurosci. 8, 99–11210.3758/CABN.8.1.99
    1. Meloy M. G., Russo J. E., Miller E. G. (2006). Monetary incentives and mood. J. Mark. Res. 43, 267–27510.1509/jmkr.43.2.267
    1. Miller E. K., Cohen J. D. (2001). An integrative theory of prefrontal cortex function. Annu. Rev. Neurosci. 24, 167–20210.1146/annurev.neuro.24.1.167
    1. Miller N. E. (1951). “Learnable drives and rewards,” in Handbook of Experimental Psychology, ed. Stevens S. S. (Oxford: Wiley; ), 435–472
    1. Mirenowicz J., Schultz W. (1996). Preferential activation of midbrain dopamine neurons by appetitive rather than aversive stimuli. Nature 379, 449–45110.1038/379449a0
    1. Montague P. R., Dayan P., Sejnowski T. J. (1996). A framework for mesencephalic dopamine systems based on predictive hebbian learning. J. Neurosci. 16, 1936–1947
    1. Muller J., Dreisbach G., Goschke T., Hensch T., Lesch K. P., Brocke B. (2007). Dopamine and cognitive control: the prospect of monetary gains influences the balance between flexibility and stability in a set-shifting paradigm. Eur. J. Neurosci. 26, 3661–366810.1111/j.1460-9568.2007.05949.x
    1. Niv Y., Daw N. D., Joel D., Dayan P. (2007). Tonic dopamine: opportunity costs and the control of response vigor. Psychopharmacology (Berl.) 191, 507–52010.1007/s00213-006-0502-4
    1. O’Reilly R. C., Frank M. J. (2006). Making working memory work: a computational model of learning in the prefrontal cortex and basal ganglia. Neural Comput. 18, 283–32810.1162/089976606775093909
    1. Padmala S., Pessoa L. (2011). Reward reduces conflict by enhancing attentional control and biasing visual cortical processing. J. Cogn. Neurosci. 23, 3419–343210.1162/jocn_a_00011
    1. Pessiglione M., Seymour B., Flandin G., Dolan R. J., Frith C. D. (2006). Dopamine-dependent prediction errors underpin reward-seeking behaviour in humans. Nature 442, 1042–104510.1038/nature05051
    1. Pessoa L. (2008). On the relationship between emotion and cognition. Nat. Rev. Neurosci. 9, 148–15810.1038/nrn2317
    1. Pessoa L. (2009). How do emotion and motivation direct executive control? Trends Cogn. Sci. (Regul. Ed.) 13, 160–16610.1016/j.tics.2009.01.006
    1. Pochon J. B., Levy R., Fossati P., Lehericy S., Poline J. B., Pillon B., Le Bihan D., Dubois B. (2002). The neural system that bridges reward and cognition in humans: an fmri study. Proc. Natl. Acad. Sci. U.S.A. 99, 5669–567410.1073/pnas.082111099
    1. Robbins T. W., Everitt B. J. (1996). Neurobehavioural mechanisms of reward and motivation. Curr. Opin. Neurobiol. 6, 228–23610.1016/S0959-4388(96)80077-8
    1. Rolls E. T. (2000). Precis of the brain and emotion. Behav. Brain Sci. 23, 177–191; discussion 192–233.10.1017/S0140525X00512424
    1. Roseman I. J. (2008). “Motivations and emotivations: approach, avoidance, and other tendencies in motivated and emotional behavior,” in Handbook of Approach and Avoidance Motivation, ed. Elliot A. J. (New York: Psychology Press; ), 343–366
    1. Rowe G., Hirsh J. B., Anderson A. K. (2007). Positive affect increases the breadth of attentional selection. Proc. Natl. Acad. Sci. U.S.A. 104, 383–38810.1073/pnas.0705390104
    1. Satterthwaite T. D., Green L., Myerson J., Parker J., Ramaratnam M., Buckner R. L. (2007). Dissociable but inter-related systems of cognitive control and reward during decision making: evidence from pupillometry and event-related fmri. Neuroimage 37, 1017–103110.1016/j.neuroimage.2007.04.066
    1. Savine A. C., Beck S. M., Edwards B. G., Chiew K. S., Braver T. S. (2010). Enhancement of cognitive control by approach and avoidance motivational states. Cogn. Emot. 24, 338–35610.1080/02699930903381564
    1. Savine A. C., Braver T. S. (2010). Motivated cognitive control: reward incentives modulate preparatory neural activity during task-switching. J. Neurosci. 30, 10294–1030510.1523/JNEUROSCI.2052-10.2010
    1. Sawaguchi T., Goldman-Rakic P. S. (1991). D1 dopamine receptors in prefrontal cortex: involvement in working memory. Science 251, 947–95010.1126/science.1825731
    1. Sawaguchi T., Goldman-Rakic P. S. (1994). The role of d1-dopamine receptor in working memory: local injections of dopamine antagonists into the prefrontal cortex of rhesus monkeys performing an oculomotor delayed-response task. J. Neurophysiol. 71, 515–528
    1. Sawaguchi T., Matsumura M., Kubota K. (1988). Dopamine enhances the neuronal activity of spatial short-term memory task in the primate prefrontal cortex. Neurosci. Res. 5, 465–47310.1016/0168-0102(88)90030-2
    1. Sawaguchi T., Matsumura M., Kubota K. (1990). Effects of dopamine antagonists on neuronal activity related to a delayed response task in monkey prefrontal cortex. J. Neurophysiol. 63, 1401–1412
    1. Schultz W. (1998). Predictive reward signal of dopamine neurons. J. Neurophysiol. 80, 1–27
    1. Schultz W. (2002). Getting formal with dopamine and reward. Neuron 36, 241–26310.1016/S0896-6273(02)00967-4
    1. Schultz W., Dayan P., Montague P. R. (1997). A neural substrate of prediction and reward. Science 275, 1593–159910.1126/science.275.5306.1593
    1. Servan-Schreiber D., Cohen J. D., Steingard S. (1996). Schizophrenic deficits in the processing of context. A test of a theoretical model. Arch. Gen. Psychiatry 53, 1105–1112
    1. Simon H. (1967). Motivational and emotional controls of cognition. Psychol. Rev. 74, 29–3910.1037/h0024127
    1. Smith E. E., Jonides J. (1998). Neuroimaging analyses of human working memory. Proc. Natl. Acad. Sci. U.S.A. 95, 12061–1206810.1073/pnas.95.3.876
    1. Strack F., Martin L. L., Stepper S. (1988). Inhibiting and facilitating conditions of the human smile: a nonobtrusive test of the facial feedback hypothesis. J. Pers. Soc. Psychol. 54, 768–77710.1037/0022-3514.54.5.768
    1. Taylor S. F., Welsh R. C., Wager T. D., Phan K. L., Fitzgerald K. D., Gehring W. J. (2004). A functional neuroimaging study of motivation and executive function. Neuroimage 21, 1045–105410.1016/j.neuroimage.2003.10.032
    1. van Steenbergen H., Band G. P., Hommel B. (2009). Reward counteracts conflict adaptation. Evidence for a role of affect in executive control. Psychol. Sci. 20, 1473–147710.1111/j.1467-9280.2009.02470.x
    1. Watanabe M. (1996). Reward expectancy in primate prefrontal neurons. Nature 382, 629–63210.1038/382629a0
    1. Watanabe M., Hikosaka K., Sakagami M., Shirakawa S. (2002). Coding and monitoring of motivational context in the primate prefrontal cortex. J. Neurosci. 22, 2391–2400
    1. Watson D., Clark L. A., Tellegen A. (1988). Development and validation of brief measures of positive and negative affect: the panas scales. J. Pers. Soc. Psychol. 54, 1063–107010.1037/0022-3514.54.6.1063
    1. Williams G. V., Goldman-Rakic P. S. (1995). Modulation of memory fields by dopamine d1 receptors in prefrontal cortex. Nature 376, 572–57510.1038/376010a0
    1. Winkielman P., Berridge K. C., Wilbarger J. L. (2005). Unconscious affective reactions to masked happy versus angry faces influence consumption behavior and judgments of value. Pers. Soc. Psychol. Bull. 31, 121–13510.1177/0146167204271309
    1. Wise R. A., Rompre P. P. (1989). Brain dopamine and reward. Annu. Rev. Psychol. 40, 191–22510.1146/annurev.ps.40.020189.001203
    1. Yan-Mei W., De-Jun G. (2008). The effects of positive emotions on task switching. Acta Psychol. Sin. 40, 301–30610.3724/SP.J.1041.2008.00301
    1. Zajonc R. (1980). Feeling and thinking: preferences need no inferences. Am. Psychol. 35, 151–17510.1037/0003-066X.35.7.662
    1. Zedelius C. M., Veling H., Aarts H. (2010). Boosting or choking – how conscious and unconscious reward processing modulate the active maintenance of goal-relevant information. Conscious. Cogn. 20, 355–36210.1016/j.concog.2010.05.001

Source: PubMed

Sponsors and Collaborators

Medical Conditions

Drug Interventions

3
Subscribe