Selective representation of relevant information by neurons in the primate prefrontal cortex


The severe limitation of the capacity of working memory, the ability to store temporarily and manipulate information1, necessitates mechanisms that restrict access to it. Here we report tests to discover whether the activity of neurons in the prefrontal (PF)cortex, the putative neural correlate of working memory2,3,4,5,6,7,8, might reflect these mechanisms and preferentially represent behaviourally relevant information. Monkeys performed a ‘delayed-matching-to-sample’ task with an array of three objects. Only one of the objects in the array was relevant for task performance and the monkeys needed to find that object (the target) and remember its location. For many PF neurons, activity to physically identical arrays varied with the target location; the location of the non-target objects had little or no influence on activity. Information about the target location was present in activity as early as 140 ms after array onset. Also, information about which object was the target was reflected in the sustained activity of many PF neurons. These results suggest that the prefrontal cortex is involved in selecting and maintaining behaviourally relevant information.

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Figure 1: The behavioural task and recording sites.
Figure 2: Delay activity from a single PF neuron that varied with the location of the target object.
Figure 3: Time course of location and object effects for cells showing those effects.


  1. 1

    Baddeley, A. Working Memory (Clarendon, Oxford, (1986).

    Google Scholar 

  2. 2

    Fuster, J. M. & Alexander, G. E. Neuron activity related to short-term memory. Science 173, 652–654 (1971).

    ADS  CAS  Article  Google Scholar 

  3. 3

    Kubota, K. & Niki, H. Prefrontal cortical unit activity and delayed alternation performance in monkeys. J. Neurophysiol. 34, 337–347 (1971).

    CAS  Article  Google Scholar 

  4. 4

    Funahashi, S., Bruce, C. J. & Goldman-Rakic, P. S. Mnemonic coding of visual space in the monkey's dorsolateral prefrontal cortex. J. Neurophysiol. 61, 331–349 (1989).

    CAS  Article  Google Scholar 

  5. 5

    di Pellegrino, G. & Wise, S. P. Aneurophysiological comparison of three distinct regions of the primate frontal lobe. Brain 114, 951–978 (1991).

    Article  Google Scholar 

  6. 6

    Miller, E. K., Erickson, C. A. & Desimone, R. Neural mechanisms of visual working memory in prefrontal cortex of the macaque. J. Neurosci. 16, 5154–5167 (1996).

    CAS  Article  Google Scholar 

  7. 7

    Rao, S. C., Rainer, G. & Miller, E. K. Integration of what and where in the primate prefrontal cortex. Science 276, 821–824 (1997)

    CAS  Article  Google Scholar 

  8. 8

    Hasegawa, R., Sawaguchi, T. & Kubota, K. Monkey prefrontal neuronal activity coding the forthcoming saccade in an oculomotor delayed matching to sample task. J. Neurophysiol. 79, 322–333 (1998).

    CAS  Article  Google Scholar 

  9. 9

    Hoffman, J. E. & Subramaniam, B. Saccadic eye movement and visual selective attention. Percept. Psychophys. 57, 787–795 (1995).

    CAS  Article  Google Scholar 

  10. 10

    Shepard, M., Findlay, J. M. & Hockey, R. J. The relationship between eye movements and spatial attention. Q. J. Exp. Psychol. 38A, 475–491 (1997).

    Google Scholar 

  11. 11

    Miller, G. A. The magic number seven plus or minus two: some limits on capacity for processing information. Psychol. Rev. 63, 81–97 (1956).

    CAS  Article  Google Scholar 

  12. 12

    Kahneman, D. Attention and Effort (Prentice-Hall, Englewood Cliffs, New Jersey, (1973).

    Google Scholar 

  13. 13

    Luck, S. J. & Vogel, E. K. The capacity of visual working memory for features and conjunctions. Nature 390, 279–281 (1997).

    ADS  CAS  Article  Google Scholar 

  14. 14

    Duncan, J. & Humphreys, G. W. Visual search and similarity. Psychol. Rev. 96, 433–458 (1989).

    CAS  Article  Google Scholar 

  15. 15

    Desimone, R. & Duncan, J. Neural mechanisms of selective visual attention. Annu. Rev. Neurosci. 18, 193–222 (1995).

    CAS  Article  Google Scholar 

  16. 16

    Gottlieb, J. P., Kusonoki, M. & Goldberg, M. E. The representation of visual salience in monkey parietal cortex. Nature 391, 481–484 (1998).

    ADS  CAS  Article  Google Scholar 

  17. 17

    Chelazzi, L., Miller, E. K., Duncan, J. & Desimone, R. Aneural basis for visual search in inferior temporal (IT) cortex. Nature 363, 345–347 (1993).

    ADS  CAS  Article  Google Scholar 

  18. 18

    Luck, S. J., Chelazzi, L., Hillyard, S. A. & Desimone, R. Neural mechanisms of spatial selective attention in areas V1, V2, and V4 of macaque visual cortex. J. Neurophysiol. 77, 24–42 (1997).

    CAS  Article  Google Scholar 

  19. 19

    Moody, S. L., Wise, S. P., Di Pellegrino, G. & Zipser, D. A. Amodel that accounts for activity in primate frontal cortex during a delayed matching-to-sample task. J. Neurosci. 18, 399–410 (1998).

    CAS  Article  Google Scholar 

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We thank S. Chenchal Rao for his participation in an early phase of this experiment and M. Histed for expert animal training and computer support. This work was supported by an NINDS grant and the Pew Charitable Trusts. We thank P. Dayan, R. Desimone, S. Macknik, J. Mazer, J. Schall, R. Wehby, M. Wicherski and M.Wilson for their valuable comments.

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Correspondence to Earl K. Miller.

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Rainer, G., Asaad, W. & Miller, E. Selective representation of relevant information by neurons in the primate prefrontal cortex. Nature 393, 577–579 (1998).

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