Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Contexts and catalysts

Contexts and catalysts There has been a historical tension between theories of brain function emphasizing regional specialization and those focusing on integration across regions. This tension continues despite the pervasive use of functional neuroimaging, which enables testing of these theories in the human brain. There are instances of agreement, where regions thought to be critical for a given behavior (e.g., Broca’s area and language production) do become more active when a person engages in that behavior. However, a number of disconcerting results have also been found. These include activation in areas not thought to be important for the behavior, and lack of activation in regions thought to be critical for particular behaviors based on studies of the damaged brain. A recently proposed Neural Context hypothesis of brain function provides a mechanism that can reconcile these apparently disparate findings. The hypothesis states that the functional relevance of a brain area depends on the status of other connected areas—i.e., the context within which the region is operating. A region can participate in several behaviors through variations in its interactions with other areas. It is possible that certain critical nodes serve as Behavioural Catalysts, enabling the transition between behavioral states, without differential alterations in the measured activity. By virtue of its anatomical connections, an area could facilitate a shift in functional connectivity between one set of regions to another. An imaging study on the changing interregional interactions involving the hippocampus in learning and awareness serves as an example of neural context. In this case, the hippocampus may serve to catalyze the transition to awareness. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Neuroinformatics Springer Journals

Contexts and catalysts

McIntosh, Anthony Randal
Neuroinformatics , Volume 2 (2) – Jun 1, 2004
Download PDF
7 pages

Loading next page...
 
/lp/springer-journals/contexts-and-catalysts-kHCUU5ZEoG
Publisher
Springer Journals
Copyright
Copyright © Humana Press Inc 2004
ISSN
1539-2791
eISSN
1559-0089
DOI
10.1385/ni:2:2:175
Publisher site
See Article on Publisher Site

Abstract

There has been a historical tension between theories of brain function emphasizing regional specialization and those focusing on integration across regions. This tension continues despite the pervasive use of functional neuroimaging, which enables testing of these theories in the human brain. There are instances of agreement, where regions thought to be critical for a given behavior (e.g., Broca’s area and language production) do become more active when a person engages in that behavior. However, a number of disconcerting results have also been found. These include activation in areas not thought to be important for the behavior, and lack of activation in regions thought to be critical for particular behaviors based on studies of the damaged brain. A recently proposed Neural Context hypothesis of brain function provides a mechanism that can reconcile these apparently disparate findings. The hypothesis states that the functional relevance of a brain area depends on the status of other connected areas—i.e., the context within which the region is operating. A region can participate in several behaviors through variations in its interactions with other areas. It is possible that certain critical nodes serve as Behavioural Catalysts, enabling the transition between behavioral states, without differential alterations in the measured activity. By virtue of its anatomical connections, an area could facilitate a shift in functional connectivity between one set of regions to another. An imaging study on the changing interregional interactions involving the hippocampus in learning and awareness serves as an example of neural context. In this case, the hippocampus may serve to catalyze the transition to awareness.

Journal

Neuroinformatics – Springer Journals

Published: Jun 1, 2004

Keywords: Neuroimaging; awareness; cognition; neural networks; learning

References

  • Cortical coordination dynamics and cognition
    Bressler, S. L.; Kelso, J. A. S.
  • Imaging cognition II: An empirical review of 275 PET and fMRI studies
    Cabeza, R.; Nyberg, L.
  • Awareness and the conditioned eyeblink response
    Clark, C. M.; Squire, L. R.; Woodruff-Pak, D. S.; Steinmetz, J. E.
  • Classical conditioning and brain systems: the role of awareness
    Clark, R. E.; Squire, L. R.
  • Human prefrontal cortex is not specific for working memory: A functional MRI study
    D’Esposito, M.; Ballard, D.; Aguirre, G. K.; Zarahn, E.
  • Dynamic organization of primary motor cortex output to target muscles in adult rats. II. Rapid reorganization following motor nerve lesions
    Donoghue, J. P.; Suner, S.; Sanes; Sanes, J. N.
  • Group selection and phasic re-entrant signalling: A theory of higher brain function
    Edelman, G. M.; Mountcastle, V.; Edelman, G. M.
  • Distributed hierarchical processing in the primate cerebral cortex
    Felleman, D. J.; Van Essen, D. C.
  • Functional and effective connectivity: A synthesis
    Friston, K.
  • Dynamic representations and generative models of brain function
    Friston, K. J.; Price, C. J.
  • Degeneracy and redundancy in cognitive anatomy
    Friston, K. J.; Price, C. J.
  • Neuronal population coding of movement direction
    Georgopoulos, A. P.; Schwartz, A. B.; Kettner, R. E.
  • Distributed and overlapping representations of faces and objects in ventral temporal cortex
    Haxby, J. V.; Gobbini, M. I.; Furey, M. L.; Ishai, A.; Schouten, J. L.; Pietrini, P.
  • Neural modeling, functional brain imaging, and cognition
    Horwitz, B.; Tagamet, M. A.; McIntosh, A. R.
  • Functional interactions between the medial temporal lobes and posterior neocortex related to episodic memory retrieval
    Kohler, S.; McIntosh, A. R.; Moscovitch, M.; Winocur, G.
  • Analysis of the dynamics of interneuronal functional connections during conditioned reflex activity
    Kozlov, A. P.; Shabaev, V. V.
  • Variability in fMRI: an examination of intersession differences
    McGonigle, D. J.; Howseman, A. M.; Athwal, B. S.; Friston, K. J.; Frackowiak, R. S.; Holmes, A. P.
  • Mapping Cognition to the Brain Through Neural Interactions
    McIntosh, A. R.
  • From location to integration: How neural interactions form the basis for human cognition
    McIntosh, A. R.; Tulving, E.
  • Towards a network theory of cognition
    McIntosh, A. R.
  • Functional connectivity of the medial temporal lobe relates to learning and awareness
    McIntosh, A. R.; Rajah, M. N.; Lobaugh, N. J.
  • Differential functional connectivity of prefrontal and medial temporal cortices during episodic memory retrieval
    McIntosh, A. R.; Nyberg, L.; Bookstein, F. L.; Tulving, E.
  • Changes in limbic and prefrontal functional interactions in a working memory task for faces
    McIntosh, A. R.; Grady, C. L.; Haxby, J. V.; Ungerleider, L. G.; Horwitz, B.
  • Network analysis of cortical visual pathways mapped with PET
    McIntosh, A. R.; Grady, C. L.; Ungerleider, L. G.; Haxby, J. V.; Rapoport, S. I.; Horwitz, B.
  • Neural ensemble coding and statistical periodicity: speculations on the operation of the mind’s eye
    Milton, J. G.; Mackey, M. C.
  • Neurobiology of conscious experience
    Picton, T. W.; Stuss, D. T.
  • A critical review of PET studies of phonological processing
    Poeppel, D.
  • Information processing with population codes
    Pouget, A.; Dayan, P.; Zemel, R.
  • Plasticity in the frequency representation of primary auditory cortex following discrimination training in adult owl monkeys
    Recanzone, G. H.; Schreiner, C. E.; Merzenich, M. M.
  • The connectional organization of the cortico-thalamic system of the cat
    Scannell, J. W.; Burns, G. A.; Hilgetag, C. C.; O’Neil, M. A.; Young, M. P.
  • Connectivity and complexity: the relationship between neuroanatomy and brain dynamics
    Sporns, O.; Tononi, G.; Edelman, G. M.
  • Compu-tational analysis of functional connectivity between areas of primate cerebral cortex
    Stephan, K. E.; Hilgetag, C. C.; Burns, G. A.; O’Neill, M. A.; Young, M. P.; Kotter, R.
  • Lateralized cognitive processes and lateralized task control in the human brain
    Stephan, K. E.; Marshall, J. C.; Friston, K. J.; Rowe, J. B.; Ritzl, A.; Zilles, K.; Fink, G. R.
  • A measure of brain complexity: Relating functional segregation and integration in the nervous system
    Tononi, G.; Sporns, O.; Edelman, G. M.
  • A complexity measure for selective matching of signals by the brain
    Tononi, G.; Sporns, O.; Edelman, G. M.
  • Measures of degeneracy and redundancy in biological networks
    Tononi, G.; Sporns, O.; Edelman, G. M.
  • Memory traces in primate spinal cord produced by operant conditioning of H-reflex
    Wolpaw, J.; Lee, C.
  • The complex structure of a simple memory
    Wolpaw, J. R.
  • Context, state and the receptive fields of striatal cortex cells
    Worgotter, F.; Eysel, U. T.
  • Sparse population coding of faces in the inferotemporal cortex
    Young, M. P.; Yamane, S.