Comments on: The central role of expectation in cognition http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/ at the intersection of neuroscience and AI. Sun, 07 Sep 2008 01:30:27 +0000 http://wordpress.org/?v=2.6 By: Bayle http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1072 Bayle Sat, 10 Dec 2005 04:07:53 +0000 http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1072 Thanks for checking those out Eric. Yeah, not being able to distingush inter- from intra- area certainly makes this statistic less meaningful for the top-down vs. bottom-up question. Makes you wonder if there are any other papers out there which do distinguish. Thanks for checking those out Eric. Yeah, not being able to distingush inter- from intra- area certainly makes this statistic less meaningful for the top-down vs. bottom-up question. Makes you wonder if there are any other papers out there which do distinguish.

]]> By: Eric http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1069 Eric Fri, 09 Dec 2005 21:16:04 +0000 http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1069 Starting from your refs I found some good support for control of the LGN by higher centers, and less satisfying info about V1 cortex. If one can't distinguish local from long-range cortico-cortical synapses within cortex, then it's hard to say how much input from higher centers there might be. But thinking further, considering synapse counts without knowing the relative strengths of the synapses could give a very biased picture, so maybe "most of the connections" isn't an ideal basis for understanding function anyway. Hmmmm... needs further thought. Anyway, here's where I went: From Sherman & Guillary (2002)... p. 1698: "Although geniculate relay cells are obviously in the business of relaying retinal input to the cortex, it is important for understanding thalamic relays (and possibly other relays) to appreciate that these retinal inputs, seen morphologically as RL terminals, provide only ca. 5–10% of all synaptic inputs to relay cells." (ref. to: Van Horn, S. C., Eris¸ir, A. & Sherman, S. M. 2000 The relative distribution of synapses in the A-laminae of the lateral geniculate nucleus of the cat. J. Comp. Neurol. 416, 509–520. [This is a detailed study of the number of synapses and their sources. 83.7% of terminals are from the cortex or brainstem. Good stuff.]) p. 1698: "Interestingly, for the cells in layer 4 of the striate cortex that are postsynaptic to the geniculate inputs, a similar pattern emerges. The driver inputs to these are the geniculate axons and yet these represent only 5–10% of the synaptic inputs to these cells in cats and monkeys."(refs: Ahmed, B., Anderson, J.C., Douglas, R.J., Martin, K.A., Nelson, J.C. (1994). Polyneuronal innervation of spiny stellate neurons in cat visual cortex. J Comp Neurol 341(1):39–49. [only 6% of V1 layer 4 input is from the LGN, but they can't distinguish between highly local cortico-cortical synapses and long-range ones from higher centers. Drat.] AND Latawiec, D., Martin, K.A., Meskenaite, V. (2000). Termination of the geniculocortical projection in the striate cortex of macaque monkey: A quantitative immunoelectron microscopic study. J Comp Neurol 419(3):306-19. [only 6.9-8.7% of V1 input is from LGN, and again no distinction between local and long-range cortical input]). More recent corticofugal auditory system reviews: Suga, N., Gao, E., Zhang, Y., Ma, X., Olsen, J.F. (2000). The corticofugal system for hearing: Recent progress. Proceedings of the National Academy of Sciences USA 97(22):11807–11814. He, J. (2003). Corticofugal modulation of the auditory thalamus. Experimental Brain Research 153(4):579–590. Starting from your refs I found some good support for control of the LGN by higher centers, and less satisfying info about V1 cortex. If one can’t distinguish local from long-range cortico-cortical synapses within cortex, then it’s hard to say how much input from higher centers there might be. But thinking further, considering synapse counts without knowing the relative strengths of the synapses could give a very biased picture, so maybe “most of the connections” isn’t an ideal basis for understanding function anyway. Hmmmm… needs further thought. Anyway, here’s where I went:

From Sherman & Guillary (2002)…

p. 1698: “Although geniculate relay cells are obviously in the business of relaying retinal input to the cortex, it is important for understanding thalamic relays (and possibly other relays) to appreciate that these retinal inputs, seen morphologically as RL terminals, provide only ca. 5–10% of all synaptic inputs to relay cells.” (ref. to: Van Horn, S. C., Eris¸ir, A. & Sherman, S. M. 2000 The relative distribution of synapses in the A-laminae of the lateral geniculate nucleus of the cat. J. Comp. Neurol. 416, 509–520. [This is a detailed study of the number of synapses and their sources. 83.7% of terminals are from the cortex or brainstem. Good stuff.])

p. 1698: “Interestingly, for the cells in layer 4 of the striate cortex that are postsynaptic to the geniculate inputs, a similar pattern emerges. The driver inputs to these are the geniculate
axons and yet these represent only 5–10% of the synaptic inputs to these cells in cats and monkeys.”(refs: Ahmed, B., Anderson, J.C., Douglas, R.J., Martin, K.A., Nelson, J.C. (1994). Polyneuronal innervation of spiny stellate neurons in cat visual cortex. J Comp Neurol 341(1):39–49. [only 6% of V1 layer 4 input is from the LGN, but they can't distinguish between highly local cortico-cortical synapses and long-range ones from higher centers. Drat.] AND Latawiec, D., Martin, K.A., Meskenaite, V. (2000). Termination of the geniculocortical projection in the striate cortex of macaque monkey: A quantitative immunoelectron microscopic study. J Comp Neurol 419(3):306-19. [only 6.9-8.7% of V1 input is from LGN, and again no distinction between local and long-range cortical input]).

More recent corticofugal auditory system reviews:
Suga, N., Gao, E., Zhang, Y., Ma, X., Olsen, J.F. (2000). The corticofugal system for hearing: Recent progress. Proceedings of the National Academy of Sciences USA 97(22):11807–11814.
He, J. (2003). Corticofugal modulation of the auditory thalamus. Experimental Brain Research 153(4):579–590.

]]> By: Bayle http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1066 Bayle Fri, 09 Dec 2005 08:27:08 +0000 http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1066 hmm yeah i was looking for a ref for that too. this article cites some references; i haven't followed and verified the citations yet, though: http://www.jneurosci.org/cgi/content/full/25/23/5521 "Anatomical studies in several systems have shown that feedback projections from higher centers often vastly outnumber feedforward projections from the periphery (Cajal, 1909; Hollander, 1970; Ostapoff et al., 1990; Sherman and Guillary, 2002)." Cajal RS (1909) Histologie du système nerveux de l'Homme et des vertébrés. Paris: Maloine. Hollander H (1970) The projection from the visual cortex to the lateral geniculate body (LGB). An experimental study with silver impregnation methods in the cat. Exp Brain Res 10: 219-235. Ostapoff EM, Morest DK, Potashner SJ (1990) Uptake and retrograde transport of [3H]GABA from the cochlear nucleus to the superior olive in the guinea pig. J Chem Neuroanat 3: 285-295. Sherman SM, Guillary RW (2002) The role of the thalamus in the flow of information to the cortex. Philos Trans R Soc Lond B Biol Sci 357: 1695-1708. hmm yeah i was looking for a ref for that too.

this article cites some references; i haven’t followed and verified the citations yet, though:

http://www.jneurosci.org/cgi/content/full/25/23/5521

“Anatomical studies in several systems have shown that feedback projections from higher centers often vastly outnumber feedforward projections from the periphery (Cajal, 1909; Hollander, 1970; Ostapoff et al., 1990; Sherman and Guillary, 2002).”

Cajal RS (1909) Histologie du système nerveux de l’Homme et des vertébrés. Paris: Maloine.

Hollander H (1970) The projection from the visual cortex to the lateral geniculate body (LGB). An experimental study with silver impregnation methods in the cat. Exp Brain Res 10: 219-235.

Ostapoff EM, Morest DK, Potashner SJ (1990) Uptake and retrograde transport of [3H]GABA from the cochlear nucleus to the superior olive in the guinea pig. J Chem Neuroanat 3: 285-295.

Sherman SM, Guillary RW (2002) The role of the thalamus in the flow of information to the cortex. Philos Trans R Soc Lond B Biol Sci 357: 1695-1708.

]]> By: Eric Mercer http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1065 Eric Mercer Fri, 09 Dec 2005 07:23:10 +0000 http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1065 "The fact that most of the connections between lower-order sensory areas and higher-order areas are feedback connections from the higher to the lower" I've heard/read this from several sources without any actual citations of published evidence. I haven't actually been able to find any such evidence in PubMed or Google Scholar searches. Can anyone give me some published examples or is this just "folk wisdom." I'm not denying it's possible, just that I can't find the papers! “The fact that most of the connections between lower-order sensory areas and higher-order areas are feedback connections from the higher to the lower”

I’ve heard/read this from several sources without any actual citations of published evidence. I haven’t actually been able to find any such evidence in PubMed or Google Scholar searches. Can anyone give me some published examples or is this just “folk wisdom.” I’m not denying it’s possible, just that I can’t find the papers!

]]> By: Bayle http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1054 Bayle Mon, 05 Dec 2005 23:01:31 +0000 http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1054 Neat, thanks Christian! May I (or would you like to) copy your comment to the NeuroWiki page that I'm building about this topic, at http://purl.net/net/neurowiki/RoleOfExpectationInCognition ? Neat, thanks Christian! May I (or would you like to) copy your comment to the NeuroWiki page that I’m building about this topic, at http://purl.net/net/neurowiki/RoleOfExpectationInCognition ?

]]> By: Christian http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1041 Christian Thu, 01 Dec 2005 10:02:04 +0000 http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1041 I was very interested to read your post. For my PhD I looked at the role of expectation in the control of smooth pursuit eye movements - these are the movements we use to follow a smoothly moving target such as a bird flying by. Normally we can't perform these movements at will in the absence of a target - if we try we end up producing a series of jerky saccades instead. It seems we need the visual feedback from a smoothly moving target to make pursuit eye movements. BUT we can generate smooth pursuit movements in the absence of a target if we have a strong expectation that a target is going to appear. In this case we start moving our eyes smoothly several hundred milliseconds prior to the target, in anticipation. These anticipatory movements that are dependent on expectation can be preprogrammed in terms of speed, direction and timing based on both past experiences or on predictive cues. Both past experience and cues can inform our expectations thus allowing us to generate these anticipatory movements. References here: http://www.psychologywriter.org.uk/html/academic_papers.html I was very interested to read your post. For my PhD I looked at the role of expectation in the control of smooth pursuit eye movements - these are the movements we use to follow a smoothly moving target such as a bird flying by. Normally we can’t perform these movements at will in the absence of a target - if we try we end up producing a series of jerky saccades instead. It seems we need the visual feedback from a smoothly moving target to make pursuit eye movements. BUT we can generate smooth pursuit movements in the absence of a target if we have a strong expectation that a target is going to appear. In this case we start moving our eyes smoothly several hundred milliseconds prior to the target, in anticipation. These anticipatory movements that are dependent on expectation can be preprogrammed in terms of speed, direction and timing based on both past experiences or on predictive cues. Both past experience and cues can inform our expectations thus allowing us to generate these anticipatory movements. References here: http://www.psychologywriter.org.uk/html/academic_papers.html

]]> By: Stephen http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1035 Stephen Sun, 27 Nov 2005 07:11:52 +0000 http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1035 This view is also promulgated in <a href="http://www.amazon.com/gp/product/0262621630/002-4550024-5258426?v=glance&n=283155&n=507846&s=books&v=glance" rel="nofollow">Llinas' I of the Vortex</a>. This view is also promulgated in Llinas’ I of the Vortex.

]]> By: Bayle http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1028 Bayle Wed, 23 Nov 2005 09:34:11 +0000 http://neurodudes.com/2005/11/22/the-central-role-of-expectation-in-cognition/#comment-1028 "Kosslyn, Hawkins and others have long been avid proponents of the view that sensory processing (as well as other aspects of cognition) is best understood as centered around prediction and prior expectation, not incoming sensory data." --- um, at least, that's how i interpret their views, i could be wrong “Kosslyn, Hawkins and others have long been avid proponents of the view that sensory processing (as well as other aspects of cognition) is best understood as centered around prediction and prior expectation, not incoming sensory data.” — um, at least, that’s how i interpret their views, i could be wrong

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