Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Experience-dependent representation of visual categories in parietal cortex

Nature volume 443, pages 85–88 (2006)Cite this article

Abstract

Categorization is a process by which the brain assigns meaning to sensory stimuli. Through experience, we learn to group stimuli into categories, such as ‘chair’, ‘table’ and ‘vehicle’, which are critical for rapidly and appropriately selecting behavioural responses1,2. Although much is known about the neural representation of simple visual stimulus features (for example, orientation, direction and colour), relatively little is known about how the brain learns and encodes the meaning of stimuli. We trained monkeys to classify 360° of visual motion directions into two discrete categories, and compared neuronal activity in the lateral intraparietal (LIP) and middle temporal (MT) areas, two interconnected brain regions3 known to be involved in visual motion processing4,5,6. Here we show that neurons in LIP—an area known to be centrally involved in visuo-spatial attention7,8,9, motor planning10,11,12,13 and decision-making14,15,16—robustly reflect the category of motion direction as a result of learning. The activity of LIP neurons encoded directions of motion according to their category membership, and that encoding shifted after the monkeys were retrained to group the same stimuli into two new categories. In contrast, neurons in area MT were strongly direction selective but carried little, if any, explicit category information. This indicates that LIP might be an important nexus for the transformation of visual direction selectivity to more abstract representations that encode the behavioural relevance, or meaning, of stimuli.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Behavioural task.
Figure 2: Examples of three category-selective LIP neurons.
Figure 3: Category effects across the LIP population.
Figure 4: LIP category selectivity followed retraining.

Similar content being viewed by others

References

  1. Ashby, F. G. & Maddox, W. T. Human category learning. Annu. Rev. Psychol. 56, 149–178 (2005)

    Article  PubMed  Google Scholar 

  2. Barsalou, L. W. Cognitive Psychology: An Overview for Cognitive Scientists (Erlbaum, Hillsdale, New Jersey, 1992)

    Google Scholar 

  3. Lewis, J. W. & Van Essen, D. C. Corticocortical connections of visual, sensorimotor, and multimodal processing areas in the parietal lobe of the macaque monkey. J. Comp. Neurol. 428, 112–137 (2000)

    Article  CAS  PubMed  Google Scholar 

  4. Born, R. T. & Bradley, D. C. Structure and function of visual area MT. Annu. Rev. Neurosci. 28, 157–189 (2005)

    Article  CAS  PubMed  Google Scholar 

  5. Eskandar, E. N. & Assad, J. A. Dissociation of visual, motor and predictive signals in parietal cortex during visual guidance. Nature Neurosci. 2, 88–93 (1999)

    Article  CAS  PubMed  Google Scholar 

  6. Williams, Z. M., Elfar, J. C., Eskandar, E. N., Toth, L. J. & Assad, J. A. Parietal activity and the perceived direction of ambiguous apparent motion. Nature Neurosci. 6, 616–623 (2003)

    Article  CAS  PubMed  Google Scholar 

  7. Colby, C. L., Duhamel, J. R. & Goldberg, M. E. Visual, presaccadic, and cognitive activation of single neurons in monkey lateral intraparietal area. J. Neurophysiol. 76, 2841–2852 (1996)

    Article  CAS  PubMed  Google Scholar 

  8. Colby, C. L. & Goldberg, M. E. Space and attention in parietal cortex. Annu. Rev. Neurosci. 22, 319–349 (1999)

    Article  CAS  PubMed  Google Scholar 

  9. Bisley, J. W. & Goldberg, M. E. Neuronal activity in the lateral intraparietal area and spatial attention. Science 299, 81–86 (2003)

    Article  ADS  CAS  PubMed  Google Scholar 

  10. Snyder, L. H., Batista, A. P. & Andersen, R. A. Coding of intention in the posterior parietal cortex. Nature 386, 167–170 (1997)

    Article  ADS  CAS  PubMed  Google Scholar 

  11. Batista, A. P., Buneo, C. A., Snyder, L. H. & Andersen, R. A. Reach plans in eye-centered coordinates. Science 285, 257–260 (1999)

    Article  CAS  PubMed  Google Scholar 

  12. Buneo, C. A., Jarvis, M. R., Batista, A. P. & Andersen, R. A. Direct visuomotor transformations for reaching. Nature 416, 632–636 (2002)

    Article  ADS  CAS  PubMed  Google Scholar 

  13. Andersen, R. A. & Buneo, C. A. Intentional maps in posterior parietal cortex. Annu. Rev. Neurosci. 25, 189–220 (2002)

    Article  CAS  PubMed  Google Scholar 

  14. Platt, M. L. & Glimcher, P. W. Neural correlates of decision variables in parietal cortex. Nature 400, 233–238 (1999)

    Article  ADS  CAS  PubMed  Google Scholar 

  15. Shadlen, M. N. & Newsome, W. T. Neural basis of a perceptual decision in the parietal cortex (area LIP) of the rhesus monkey. J. Neurophysiol. 86, 1916–1936 (2001)

    Article  CAS  PubMed  Google Scholar 

  16. Huk, A. C. & Shadlen, M. N. Neural activity in macaque parietal cortex reflects temporal integration of visual motion signals during perceptual decision making. J. Neurosci. 25, 10420–10436 (2005)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Ghose, G. M. Learning in mammalian sensory cortex. Curr. Opin. Neurobiol. 14, 513–518 (2004)

    Article  CAS  PubMed  Google Scholar 

  18. Freedman, D. J., Riesenhuber, M., Poggio, T. & Miller, E. K. Categorical representation of visual stimuli in the primate prefrontal cortex. Science 291, 312–316 (2001)

    Article  ADS  CAS  PubMed  Google Scholar 

  19. Freedman, D. J., Riesenhuber, M., Poggio, T. & Miller, E. K. Visual categorization and the primate prefrontal cortex: neurophysiology and behavior. J. Neurophysiol. 88, 914–928 (2002)

    Article  Google Scholar 

  20. Miller, E. K. & Cohen, J. D. An integrative theory of prefrontal cortex function. Annu. Rev. Neurosci. 24, 167–202 (2001)

    Article  CAS  PubMed  Google Scholar 

  21. Sigala, N. & Logothetis, N. K. Visual categorization shapes feature selectivity in the primate temporal cortex. Nature 415, 318–320 (2002)

    Article  ADS  CAS  PubMed  Google Scholar 

  22. Freedman, D. J., Riesenhuber, M., Poggio, T. & Miller, E. K. Experience-dependent sharpening of visual shape selectivity in inferior temporal cortex. Cereb. Cortex (in the press)

  23. Vogels, R. Categorization of complex visual images by rhesus monkeys. Eur. J. Neurosci. 11, 1223–1238 (1999)

    Article  CAS  PubMed  Google Scholar 

  24. Freedman, D. J., Riesenhuber, M., Poggio, T. & Miller, E. K. A comparison of primate prefrontal and inferior temporal cortices during visual categorization. J. Neurosci. 23, 5235–5246 (2003)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Bisley, J. W., Krisna, B. S. & Goldberg, M. E. A rapid and precise on-response in posterior parietal cortex. J. Neurosci. 24, 1833–1838 (2004)

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Toth, L. J. & Assad, J. A. Dynamic coding of behaviorally relevant stimuli in parietal cortex. Nature 415, 165–168 (2002)

    Article  ADS  CAS  PubMed  Google Scholar 

  27. Nieder, A. & Miller, E. K. A parieto-frontal network for visual numerical information in the monkey. Proc. Natl Acad. Sci. USA 101, 7457–7462 (2004)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  28. Stoet, G. & Snyder, L. H. Single neurons in posterior parietal cortex (PPC) of monkeys encode cognitive set. Neuron 42, 1003–1012 (2004)

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

We thank J. Ditterich, A. Fanini, V. Ferrera, J. Fitzgerald, C. Freedman, T. Herrington, M. Histed, G. Maimon, E. Miller, C. Pack, C. Padoa-Schioppa, A. Seitz and J. Wallis for comments, help and discussions, and K. Irwin, T. Lafratta and J. LeBlanc for technical assistance. This work was supported by the National Eye Institute (NEI) and the McKnight Endowment Fund for Neuroscience, and a Kirschstein postdoctoral National Research Service Award from the NEI to D.J.F. Author Contributions D.J.F. performed all aspects of this study including the experimental design, data collection and analysis, and writing the manuscript. J.A.A. assisted in experimental design, data analysis and manuscript preparation.

Author information

Authors and Affiliations

  1. Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Massachusetts, 02115, Boston, USA

    David J. Freedman & John A. Assad

Authors
  1. David J. Freedman
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. John A. Assad
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to David J. Freedman.

Ethics declarations

Competing interests

Reprints and permissions information is available at www.nature.com/reprints. The authors declare no competing financial interests.

Supplementary information

Supplementary Notes

This file contains Supplementary Methods and Supplementary Results. (DOC 44 kb)

Supplementary Figures

This file contains Supplementary Figures 1—8. (PDF 406 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Freedman, D., Assad, J. Experience-dependent representation of visual categories in parietal cortex. Nature 443, 85–88 (2006). https://doi.org/10.1038/nature05078

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature05078

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing