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Cell directional spread determines accuracy, precision, and length of the neuronal population vector

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Abstract

The neuronal population vector (NPV) for movement direction is the sum of weighted neuronal directional contributions. Based on theoretical considerations, we proposed recently that the sharpness of tuning will impact the directional precision, accuracy, and length of the NPV, such that sharper tuning will yield NPV with higher precision, higher accuracy, and shorter length (Mahan and Georgopoulos in Front Neural Circuits 7:92, 2013). Furthermore, we proposed that controlling the inhibitory drive in a local network could be the mechanism by which the sharpness of directional tuning would be varied, resulting in a continuous specification and control of movement’s directional precision, accuracy, and speed (Mahan and Georgopoulos in Front Neural Circuits 7:92, 2013, Fig. 5). As a first step in testing this idea, here we analyzed data from 899 cells recorded in the motor cortex during performance of a center → out task. There were two major findings. First, directional selectivity varied with cell activity, such that it was higher in cells with lower mean discharge rates. And second, NPVs calculated from subsets of cells with higher directional selectivity (and, correspondingly, lower mean discharge rates) were more accurate (i.e., closer to the movement), precise (i.e., less variable), and shorter (i.e., slower; Schwartz in Science 265:540–542, 1994). These findings confirm our predictions above made from modeling (Mahan and Georgopoulos in Front Neural Circuits 7:92, 2013) and provide a simple mechanism by which desired attributes of the directional motor command can be implemented. We hypothesize that the inhibitory drive in a local network is controlled directly and independently of recurrent collaterals or common excitatory inputs to other cells. This could be achieved by a private excitation/inhibition of key inhibitory interneurons in a way similar to that in operation for Renshaw cells in the spinal cord. The presence of such a private line of inhibitory control remains to be investigated.

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References

  • Amirikian B, Georgopoulos AP (2000) Directional tuning profiles of motor cortical cells. Neurosci Res 36:73–79

    Article  CAS  PubMed  Google Scholar 

  • Benevento LA, Creutzfeldt OD, Kuhnt U (1972) Significance of intracortical inhibition in the visual cortex. Nat New Biol 238:124–126

    Article  CAS  PubMed  Google Scholar 

  • Cox DR, Lewis PAW (1966) The statistical analysis of series of events. Chapman Hall, London

    Book  Google Scholar 

  • Crowe DA, Averbeck BB, Chafee MV, Georgopoulos AP (2005) Dynamics of parietal neural activity during spatial cognitive processing. Neuron 47:885–891. doi:10.1016/j.neuron.2005.08.005

    Article  CAS  PubMed  Google Scholar 

  • Ferster D, Miller KD (2000) Neural mechanisms of orientation selectivity in the visual cortex. Annu Rev Neurosci 23:441–471. doi:10.1146/annurev.neuro.23.1.441

    Article  CAS  PubMed  Google Scholar 

  • Fisher NI, Lee AJ (1983) A correlation coefficient for circular data. Biometrika 70:327–332

    Article  Google Scholar 

  • Fitts PM (1954) The information capacity of the human motor system in controlling the amplitude of movement. J Exp Psychol 47:381–391

    Article  CAS  PubMed  Google Scholar 

  • Georgopoulos AP, Stefanis CN (2007) Local shaping of function in the motor cortex: motor contrast, directional tuning. Brain Res Rev 55:383–389

    Article  PubMed  Google Scholar 

  • Georgopoulos AP, Stefanis C (2010) The motor cortical circuit. In: Shepherd G, Grillner S (eds) Brain microcircuits. Oxford, New York, pp 39–45. doi:10.1016/j.brainresrev.2007.05.001

  • Georgopoulos AP, Kalaska JF, Caminiti R, Massey JT (1982) On the relations between the direction of two-dimensional arm movements and cell discharge in primate motor cortex. J Neurosci 2:1527–1537

    CAS  PubMed  Google Scholar 

  • Georgopoulos AP, Caminiti R, Kalaska JF, Massey JT (1983) Spatial coding of movement: a hypothesis concerning the coding of movement direction by motor cortical populations. Exp Brain Res Suppl 7:327–336

    Article  Google Scholar 

  • Georgopoulos AP, Schwartz AB, Kettner RE (1986) Neuronal population coding of movement direction. Science 233:1416–1419

    Article  CAS  PubMed  Google Scholar 

  • Georgopoulos AP, Kettner RE, Schwartz AB (1988) Primate motor cortex and free arm movements to visual targets in three-dimensional space. II. Coding of the direction of movement by a neuronal population. J Neurosci 8:2928–2937

    CAS  PubMed  Google Scholar 

  • Georgopoulos AP, Lurito JT, Petrides M, Schwartz AB, Massey JT (1989) Mental rotation of the neuronal population vector. Science 243:234–236

    Article  CAS  PubMed  Google Scholar 

  • Hultborn H, Pierrot-Deseilligny E (1979) Changes in recurrent inhibition during voluntary soleus contractions in man studied by an H-reflex technique. J Physiol (Lond) 297:229–251

    CAS  PubMed Central  Google Scholar 

  • Hultborn H, Lindstrom S, Wigstrom H (1979) On the function of recurrent inhibition in the spinal cord. Exp Brain Res 37:399–403

    Article  CAS  PubMed  Google Scholar 

  • Kang K, Shelley M, Sompolinsky H (2003) Mexican hats and pinwheels in visual cortex. Proc Natl Acad Sci USA 100:2848–2853. doi:10.1073/pnas.0138051100

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  • Lee SH, Kwan AC, Zhang S, Phoumthipphavong V, Flannery JG, Masmanidis SC, Taniguchi H, Huang ZJ, Zhang F, Boyden ES, Deisseroth K, Dan Y (2012) Activation of specific interneurons improves V1 feature selectivity and visual perception. Nature 488:379–383. doi:10.1038/nature11312

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  • Li G, Yang Y, Liang Z, Xia J, Yang Y, Zhou Y (2008) GABA-mediated inhibition correlates with orientation selectivity in primary visual cortex of cat. Neuroscience 155:914–922. doi:10.1016/j.neuroscience.2008.06.032

    Article  CAS  PubMed  Google Scholar 

  • Li YT, Ma WP, Pan CJ, Zhang LI, Tao HW (2012a) Broadening of cortical inhibition mediates developmental sharpening of orientation selectivity. J Neurosci 32:3981–3991. doi:10.1523/JNEUROSCI.5514-11.2012

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  • Li YT, Ma WP, Li LY, Ibrahim LA, Wang SZ, Tao HW (2012b) Broadening of inhibitory tuning underlies contrast-dependent sharpening of orientation selectivity in mouse visual cortex. J Neurosci 32:16466–16477. doi:10.1523/JNEUROSCI.3221-12.2012

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  • Lurito JT, Georgakopoulos T, Georgopoulos AP (1991) Cognitive spatial-motor processes. 7. The making of movements at an angle from a stimulus direction: studies of motor cortical activity at the single cell and population levels. Exp Brain Res 87:562–580

    Article  CAS  PubMed  Google Scholar 

  • MacKenzie SI (1992) Fitts’ law as a research and design tool in human–computer interaction. Hum Comput Interact 7:91–139

    Article  Google Scholar 

  • Mahan MY, Georgopoulos AP (2013) Motor directional tuning across brain areas: directional resonance and the role of inhibition for directional accuracy. Front Neural Circuits 7:92. doi:10.3389/fncir.2013.00092

    Article  PubMed Central  PubMed  Google Scholar 

  • Mardia KV (1972) Statistics of directional data. Academic Press, New York

    Google Scholar 

  • Merchant H, Naselaris T, Georgopoulos AP (2008) Dynamic sculpting of directional tuning in the primate motor cortex during three-dimensional reaching. J Neurosci 28:9164–9172. doi:10.1523/JNEUROSCI.1898-08.2008

    Article  CAS  PubMed  Google Scholar 

  • Pellizzer G, Sargent P, Georgopoulos AP (1995) Motor cortical activity in a context-recall task. Science 269:702–705

    Article  CAS  PubMed  Google Scholar 

  • Schwartz AB (1994) Direct cortical representation of drawing. Science 265:540–542

    Article  CAS  PubMed  Google Scholar 

  • Schwartz AB, Kettner RE, Georgopoulos AP (1988) Primate motor cortex and free arm movements to visual targets in three-dimensional space. I. Relations between single cell discharge and direction of movement. J Neurosci 8:2913–2927

    CAS  PubMed  Google Scholar 

  • Shapley R, Hawken M, Ringach DL (2003) Dynamics of orientation selectivity in the primary visual cortex and the importance of cortical inhibition. Neuron 38:689–699

    Article  CAS  PubMed  Google Scholar 

  • Sillito AM (1975) The contribution of inhibitory mechanisms to the receptive field properties of neurones in the striate cortex of the cat. J Physiol 250:305–329

    CAS  PubMed Central  PubMed  Google Scholar 

  • Sillito AM (1979) Inhibitory mechanisms influencing complex cell orientation selectivity and their modification at high resting discharge levels. J Physiol 289:33–53

    CAS  PubMed Central  PubMed  Google Scholar 

  • Snedecor GW, Cochran WG (1989) Statistical methods. Iowa State University Press, Ames, IA

  • Stefanis C (1969) Interneuronal mechanisms in the cortex. In: Brazier MAB (ed) The interneuron. University of California Press, Berkeley, pp 497–526

    Google Scholar 

  • Stefanis C, Jasper H (1964) Recurrent collateral inhibition in pyramidal tract neurons. J Neurophysiol 27:855–877

    CAS  PubMed  Google Scholar 

  • Troyer TW, Krukowski AE, Priebe NJ, Miller KD (1998) Contrast-invariant orientation tuning in cat visual cortex: thalamocortical input tuning and correlation-based intracortical connectivity. J Neurosci 18:5908–5927

    CAS  PubMed  Google Scholar 

  • Xing D, Ringach DL, Hawken MJ, Shapley RM (2011) Untuned suppression makes a major contribution to the enhancement of orientation selectivity in macaque v1. J Neurosci 31:15972–15982. doi:10.1523/JNEUROSCI.2245-11.2011

    Article  CAS  PubMed Central  PubMed  Google Scholar 

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Acknowledgments

This work was supported by the American Legion Brain Sciences Chair, University Minnesota.

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Correspondence to Apostolos P. Georgopoulos.

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Georgopoulos, A.P. Cell directional spread determines accuracy, precision, and length of the neuronal population vector. Exp Brain Res 232, 2391–2405 (2014). https://doi.org/10.1007/s00221-014-3936-7

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