Abstract
Forty-five years ago, Roger Sperry, Joseph Bogen and I embarked on what are now known as the modern split-brain studies. These experiments opened up new frontiers in brain research and gave rise to much of what we know about hemispheric specialization and integration. The latest developments in split-brain research build on the groundwork laid by those early studies. Split-brain methodology, on its own and in conjunction with neuroimaging, has yielded insights into the remarkable regional specificity of the corpus callosum as well as into the integrative role of the callosum in the perception of causality and in our perception of an integrated sense of self.
This is a preview of subscription content, access via your institution
Relevant articles
Open Access articles citing this article.
-
A frontal transcallosal inhibition loop mediates interhemispheric balance in visuospatial processing
Nature Communications Open Access 25 August 2023
-
Mapping lesion, structural disconnection, and functional disconnection to symptoms in semantic aphasia
Brain Structure and Function Open Access 04 July 2022
-
Lessons from behavioral lateralization in olfaction
Brain Structure and Function Open Access 01 October 2021
Access options
Subscribe to this journal
Receive 12 print issues and online access
$189.00 per year
only $15.75 per issue
Rent or buy this article
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout


References
Lashley, K. S. In search of the engram. Symp. Soc. Exp. Biol. 4, 454–482 (1950).
Hebb, D. O. The Organization of Behavior: a Neuropsychological Theory (Wiley, New York, USA, 1949).
Sperry, R. W. Chemoaffinity in the orderly growth of nerve fiber patterns and connections. Proc. Natl Acad. Sci. USA 50, 703–710 (1963).
Weiss, P. A. In vitro experiments on the factors determining the course of the outgrowing nerve fiber. J. Exp. Zool. 68, 393–448 (1934).
Van Wagenen, W. P & Herren, R. Y. Surgical division of commissural pathways in the corpus callosum: relation to spread of an epileptic attack. Arch. Neurol. Psychiatry 44, 740–759 (1940).
Bogen, J. E. & Vogel, P. J. Cerebral commissurotomy in man. Bull. Los Angel. Neuro. Soc. 27, 169–172 (1962).
Akelaitis, A. J. A study of gnosis, praxis and language following section of the corpus callosum and anterior commissure. J. Neurosurg. 1, 94–102 (1944).
Myers, R. E. Function of the corpus callosum in interocular transfer. Brain 79, 358–363 (1956).
Myers, R. E. & Sperry, R. W. Interhemispheric communication through the corpus callosum: mnemonic carry-over between the hemispheres. Arch. Neurol. Psychiatry 80, 298–303 (1958).
Gazzaniga, M. S. Split brain research: a personal history. Cornell Univ. Alumni Q. 45, 2–12 (1982).
Lettvin, J. Y. 1981 Nobel prize for physiology or medicine. Science 214, 517–520 (1981).
Gazzaniga, M. S. Cerebral specialization and interhemispheric communication: does the corpus callosum enable the human condition? Brain 123, 1293–1326 (2000).
Zaidel, E. in Handbook of Neuropsychology Vol. 4 (eds Boller, F. & Grafman, J.) 115–150 (Elsevier, Amsterdam, 1991).
Funnell, M. G., Corballis, P. M. & Gazzaniga, M. S. Handbook of Neuropsychology 2nd Edn Vol. 1 (eds Boller, F. & Grafman, J.) 103–120 (Elsevier, Amsterdam, 2000).
Milner, B. in Interhemispheric Relations and Cerebral Dominance (ed. Mountcastle, V. B.) 177–198 (Johns Hopkins Press, Baltimore, Maryland, 1962).
Zaidel, E. & Peters, A. M. Phonological encoding and ideographic reading by the disconnected right hemisphere: two case studies. Brain and Language 14, 205–234 (1981).
Zaidel, E. in The Dual Brain (eds Benson, D. F. & Zaidel, E.) 205–231 (Guildford, New York, 1985).
Baynes, K., Eliassen, J. C., Lutsep, H. L & Gazzaniga, M. S. Modular organization of cognitive systems masked by interhemispheric integration. Science 280, 902–905 (1998).
Nebes, R. Superiority of the minor hemisphere in commissurotomized man on a test of figural unification. Brain 95, 633–638 (1972).
Nebes, R. Perception of spatial relationships by the right and left hemispheres of a commissurotomized man. Neuropsychologia 11, 285–289 (1973).
Forster, B. A., Corballis, P. M. & Corballis, M. C. Effect of luminance on successiveness discrimination in the absence of the corpus callosum. Neuropsychologia 38, 441–450 (2000).
Corballis, M. C. & Sergent, J. Imagery in a commissurotomized patient. Neuropsychologia 26, 13–26 (1988).
Corballis, P. M., Funnell, M. G. & Gazzaniga, M. S. A dissociation between spatial and identity matching in callosotomy patients. Neuroreport 10, 2183–2187 (1999).
Funnell, M. G., Corballis, P. M. & Gazzaniga, M. S. A deficit in perceptual matching in the left hemisphere of a callosotomy patient. Neuropsychologia 37, 1143–1154 (1999).
Corballis, P. M., Fendrich, R., Shapley, R. & Gazzaniga, M. S. Illusory contours and amodal completion: evidence for a functional dissociation in callosotomy patients. J. Cogn. Neurosci. 11, 459–466 (1999).
Luck, S. J., Hillyard, S. A., Mangun, G. R. & Gazzaniga, M. S. Independent hemispheric attentional systems mediate visual search in split-brain patients. Nature 342, 543–545 (1989).
Lambert, A. J. Interhemispheric interaction in the split-brain. Neuropsychologia 29, 941–948 (1991).
Corballis, M. C. Split decisions: problems in the interpretation of results from commissurotomized subjects. Behav. Brain Res. 64, 163–172 (1994).
Levy, J. & Trevarthen, C. Metacontrol of hemispheric function in human split-brain patients. J. Exp. Psychol. Hum. Percept. Perform. 2, 299–312 (1976).
Holtzman, J. D. & Gazzaniga, M. S. Dual task interactions due exclusively to limits in processing resources. Science 218, 1325–1327 (1982).
Weissman, D. H. & Banich, M. T. The cerebral hemispheres cooperate to perform complex but not simple tasks. Neuropsychology 14, 41–59 (2000).
Belger, A. & Banich, M. T. Costs and benefits of integrating information between the cerebral hemispheres: a computational perspective. Neuropsychology 12, 380–398 (1998).
Banich, M. T. & Belger, A. Interhemispheric interaction: how do the hemispheres divide and conquer a task? Cortex 26, 77–94 (1990).
Gordon, H. W., Bogen, J. E. & Sperry, R. W. Absence of deconnexion syndrome in two patients with partial section of the neocommissures. Brain 94, 327–336 (1971).
Gazzaniga, M. S. & Freedman, H. Observations on visual processes after posterior callosal section. Neurology 23, 1126–1130 (1973).
Risse, G. L., Gates, J., Lund, G., Maxwell, R. & Rubens, A. Interhemispheric transfer in patients with incomplete section of the corpus-callosum. Anatomic verification with magnetic resonance imaging. Arch. Neurol. 46, 437–443 (1989).
Gazzaniga, M. S. The split brain in man. Sci. Am. 217, 24–29 (1967).
Corballis, M. C. Visual integration in the split brain. Neuropsychologia 33, 937–959 (1995).
Baynes, K. Language and reading in the right hemisphere: highways or byways of the brain? J. Cogn. Neurosci. 2, 159–179 (1990).
Gazzaniga, M. S. Interhemispheric communication of visual learning. Neuropsychologia 4, 183–189 (1966).
Seymour, S. A., Reuter-Lorenz, P. A. & Gazzaniga, M. S. The disconnection syndrome: basic findings reaffirmed. Brain 117, 105–115 (1994).
Gazzaniga, M. S., Bogen, J. E. & Sperry, R. W. Observations on visual perception after disconnexion of the cerebral hemispheres in man. Brain 88, 221–236 (1965).
Funnell, M. G., Corballis, P. M. & Gazzaniga, M. S. Cortical and subcortical interhemispheric interactions following partial and complete callosotomy. Arch. Neurol. 57, 185–189 (2000).
Funnell, M. G., Corballis, P. M. & Gazzaniga, M. S. Insights into functional specificity of the human corpus callosum. Brain 123, 920–926 (2000).
Fabri, M. et al. Posterior corpus callosum and interhemispheric transfer of somatosensory information: an fMRI and neuropsychological study of a partially callosotomized patient. J. Cogn. Neurosci. 13, 1071–1079 (2001).
Ihori, N., Kawamura, M., Fukuzawa, K. & Kamaki, M. Somesthetic disconnection syndromes in patients with callosal lesions. Eur. Neurol. 44, 65–71 (2000).
Arguin, M. et al. Divided visuo-spatial attention systems with total and anterior callosotomy. Neuropsychologia 15, 295–302 (2000).
Basser, P. J. & Jones, D. K. Diffusion-tensor MRI: theory, experimental design and data analysis - a technical review. NMR Biomed. 15, 456–467 (2002).
Basser, P. J., Mattiello, J. & LeBihan, D. Estimation of the effective self-diffusion tensor from the NMR spin echo. J. Magn. Reson. B 103, 247–254 (1994).
Basser, P. J., Mattiello, J. & LeBihan, D. MR diffusion tensor spectroscopy and imaging. Biophys. J. 66, 259–267 (1994).
Le Bihan, D. Looking into the functional architecture of the brain with diffusion MRI. Nature Rev. Neurosci. 4, 469–480 (2003).
Sundgren, P. C. et al. Diffusion tensor imaging of the brain: review of clinical applications. Neuroradiology 46, 339–350 (2004).
Chepuri, N. B. et al. Diffusion anisotropy in the corpus callosum. Am. J. Neuroradiol. 23, 803–808 (2002).
Baird, A. A., Colvin, M. K., Van Horn, J. D., Inati, S. & Gazzaniga, M. S. Functional connectivity: integrating behavioral, DTI and fMRI data sets. J. Cogn. Neurosci. 17, 687–693 (2005).
Warrington, E. K. & Taylor, A. M. The contribution of the right parietal lobe to object recognition. Cortex 9, 152–164 (1973).
Humphreys, G. W., Price, C. J. & Riddoch, M. J. From objects to names: a cognitive neuroscience approach. Psychol. Res. 62, 118–130 (1999).
Colvin, M. K., Funnell, M. G., Hahn, B. & Gazzaniga, M. S. Identifying functional channels in the corpus callosum: correlating interhemispheric transfer time with white matter organization. Poster presented at the annual meeting of the Society for Neuroscience, San Diego, California, 2004. J. Cogn. Neurosci. 139 (suppl. 5), (2005).
Aboitiz, F. & Montiel, J. One hundred million years of interhemispheric communication: the history of the corpus callosum. Braz. J. Med. Biol. Res. 36, 409–420 (2003).
LaMantia, A. S. & Rakic, P. Cytological and quantitative characteristics of four cerebral commissures in the rhesus monkey. J. Comp. Neurol. 291, 520–537 (1990).
Banich, M. T. The missing link: the role of interhemispheric interaction in attentional processing. Brain Cogn. 36, 128–157 (1998).
Cabeza, R. Hemispheric asymmetry reduction in older adults: the HAROLD model. Psychol. Aging 17, 85–100 (2002).
Colvin, M. K., Wig, G. S., Kelley, W. M., Grafton, S. T. & Gazzaniga, M. S. Callosal organization predicts the level and effect of right frontal activity during verbal encoding on subsequent memory in healthy young adults. Soc. Neurosci. Abstr. 204.4 (2005).
Colvin, M. K. Individual differences in callosal organization: relationship to interhemispheric communication and hemispheric asymmetries. Diss. Abstr. (in the press).
Leslie, A. M. & Keeble, S. Do six-month-old infants perceive causality? Cognition 25, 265–288 (1987).
Michotte, A. The Perception of Causality (Basic Books, New York, USA, 1963) (Translated from original, published 1946).
Roser, M. E., Fugelsang, J. A., Dunbar, K. N., Corballis, P. M. & Gazzaniga, M. S. Dissociating causal perception and causal inference in the brain. Neuropsychology (in the press).
Fugelsang, J. A., Roser, M. E., Corballis, P. M., Gazzaniga, M. S. & Dunbar, K. N. Brain mechanisms underlying perceptual causality. Cogn. Brain Res. (in the press).
Turk, D. J., Heatherton, T. F., Macrae, C. N., Kelley, W. M. & Gazzaniga, M. S. Out of contact, out of mind: the distributed nature of self. Ann. NY Acad. Sci. 1001, 65–78 (2003).
Gazzaniga, M. S. One brain — two minds? Am. Sci. 60, 311–317 (1972).
Gazzaniga, M. S. & Smylie, C. S. Facial recognition and brain asymmetries: clues to underlying mechanisms. Ann. Neurol. 13, 536–540 (1983).
DeRenzi, E. Prosopagnosia in two patients with CT scan evidence of damage confined to the right-hemisphere. Neuropsychologia 24, 385–389 (1986).
Landis, T., Cummings, J. L., Christen, L., Bogen, J. E. & Imhof, H. G. Are unilateral right posterior cerebral lesions sufficient to cause prosopagnosia? Clinical and radiological findings in six additional patients. Cortex 22, 243–252 (1986).
Michel, F., Poncet, M. & Signoret, J. L. Les lesions responsables de la prosopagnosie sont-elles toujours bilateral. Rev. Neurol. (Paris) 145, 764–770 (1989) (in French).
Wada, Y. & Yamamoto, T. Selective impairment of facial recognition due to a haematoma restricted to the right fusiform and lateral occipital region. J. Neurol. Neurosurg. Psychiatry 71, 254–257 (2001).
Whiteley, A. M. & Warrington, E. K. Prosopagnosia: a clinical, psychological, and anatomical study of three patients. J. Neurol. Neurosurg. Psychiatry 40, 395–403 (1977).
Keenan, J. P., Nelson, A., O'Connor, M. & Pascual-Leone, A. Neurology: self-recognition and the right hemisphere. Nature 409, 305 (2001).
Keenan, J. P. et al. Left hand advantage in a self-face recognition task. Neuropsychologia 37, 1421–1425 (1999).
Keenan, J. P., Ganis, G, Freund, S. & Pascual-Leone, A. Self-face identification is increased with left hand responses. Laterality 5, 259–268 (2000).
Conway, M. A. et al. A positron emission tomography (PET) study of autobiographical memory retrieval. Memory 7, 679–702 (1999).
Conway, M. A. & Pleydell-Pearch, C. W. The construction of autobiographical memories in the self-memory system. Psychol. Rev. 107, 261–288 (2000).
Kircher, T. T. et al. The neural correlates of intentional and incidental self processing. Neuropsychologia 40, 683–692 (2002).
Maguire, E. A. & Mummery, C. J. Differential modulation of a common memory retrieval network revealed by positron emission tomography. Hippocampus 9, 54–61 (1999).
Turk, D. J. Mike or me? Self-recognition in a split-brain patient. Nature Neurosci. 5, 841–842 (2002).
Cooney, J. W. & Gazzaniga, M. S. Neurologic disorders and the structure of human consciousness. Trends Cogn. Sci. 7, 161–164 (2003).
Erikson, T. C. Spread of epileptic discharge. Arch. Neurol. Psychiatry 43, 429–452 (1940).
Gazzaniga, M. S., Bogen, J. E. & Sperry, R. W. Some functional effects of sectioning the cerebral commissures in man. Proc. Natl Acad. Sci. USA 48, 1765–1769 (1962).
Gazzaniga, M. S. Effects of commissurotomy on a preoperatively learned visual discrimination. Exp. Neurol. 8, 14–19 (1963).
Gazzaniga, M. S., Bogen, J. E. & Sperry, R. W. Dyspraxia following division of cerebral commissures. Arch. Neurol. 16, 606–612 (1967).
Bogen, J. E. & Gazzaniga, M. S. Cerebral commissurotomy in man — minor hemisphere dominance for certain visuospatial functions. J. Neurosurg. 23, 394–399 (1965).
Gazzaniga, M. S. & LeDoux, J. The Integrated Mind (Plenum, New York, USA, 1978).
Corballis, P. M. Visuospatial processing and the right-hemisphere interpreter. Brain Cogn. 53, 171–176 (2003).
Acknowledgements
This research was supported by National Institutes of Health grants to the author. It was also supported by a graduate reseach fellowship from the National Science Foundation to M. Colvin. I would like to thank my collaborators, M. Colvin, M. Funnell, M. Roser and D. Turk, for their scientific input as well as their assistance in reviewing this paper. I would also like to thank R. Townsend for her editorial assistance.
Author information
Authors and Affiliations
Ethics declarations
Competing interests
The author declares no competing financial interests.
Related links
Rights and permissions
About this article
Cite this article
Gazzaniga, M. Forty-five years of split-brain research and still going strong. Nat Rev Neurosci 6, 653–659 (2005). https://doi.org/10.1038/nrn1723
Issue Date:
DOI: https://doi.org/10.1038/nrn1723
This article is cited by
-
A frontal transcallosal inhibition loop mediates interhemispheric balance in visuospatial processing
Nature Communications (2023)
-
Impaired neurovascular coupling and cognitive deficits in anti-N-methyl-D-aspartate receptor encephalitis
Brain Imaging and Behavior (2022)
-
Mapping lesion, structural disconnection, and functional disconnection to symptoms in semantic aphasia
Brain Structure and Function (2022)
-
Lessons from behavioral lateralization in olfaction
Brain Structure and Function (2022)
-
Comprehensive genetic analysis confers high diagnostic yield in 16 Japanese patients with corpus callosum anomalies
Journal of Human Genetics (2021)