Sign up for one of the seminars by sending an e-mail to a.stockman@ucl.ac.uk, giving also second and third choices. Seminars will be assigned on a first-come, first-served basis. Note that the topic chosen must be distinctly different from the topic chose for the essay title. Topics already assigned are followed by the initials of the presenter in red.
Presentations should each be about 10 minutes in length. Please time your presentations before you give them. A data projector will be available in the room. If you need any further help with references, please e-mail the seminar organizers.
Titles already assigned will be denoted by the initials in red. I'm going to be away for a few days, so don't worry if this isn't updated with your choices.
A. How are the center-surround receptive fields of the retina formed and what are their significance? AS
B. What do retinal amacrine cells do? JH
C. Why are there different classes of ganglion cell in the retina? SL
D. How are distinct ON and OFF pathways generated and maintained in the retina?
E. What are the functions of the excitatory amino acid transmitters in the retina?
F. What are the functions of the inhibitory amino acid transmitters in the retina?
G. How is the electroretinogram generated and recorded? GC
H. How does the function of the Inner Plexiform Layer and Ganglion Cell layer circuitry change with changes in light level?
I. What is the function of Dopamine in the retina? DC
J. What do retinal horizontal cells do?
K. Discuss the function of convergence and divergence within the retinal circuitry.
References
General retina (everyone should be aware of the Web textbook): http://webvision.med.utah.edu
First steps in seeing. R.W Rodieck
Phototransduction references
Leibrock, C. S. (1998). "Molecular basis of dark
adaptation in rod photoreceptors." Eye 12: 511-520.
Pugh, E. N., S. Nikonov, and Lamb, T.D. (1999).
"Molecular mechanisms of vertebrate photoreceptor light adaptation."
Current Opinion on Neurobiology 9: 410-418.
Lamb, T. D. (1999). Photopigments and the biophysics of
transduction in cone photoreceptors. Color vision: From Genes to
Perception. K. Gegenfurtner and L. T. Sharpe. Cambridge, Cambridge University
Press: 89-101.
Pugh, E. N. and T. D. Lamb (2000). Phototransduction
in vertebrate rods and cones: molecular mechanisms of amplification, recovery
and light adaptation. Handbook of biological physics, Vol. 3,
Molecular mechanisms of visual transduction. D. G.
Stavenga, W. J. de Grip and E. N. Pugh. Amsterdam, Elsevier: 183-255.
Arshavsky, V. Y., T. D. Lamb, and Pugh, E.N. (2000). "G proteins and phototransduction." Annual review
of Physiology 64: 153-187.
A. Compare and contrast the properties of rod and cone vision. Why do we need two systems? AM
B. How do we see colour, and what are the limitations of our colour vision? MN
C. Describe the more common types of colour "blindness" and their causes. JG
D. Show examples of visual illusions. For some of them, provide an explanation of what the illusion tells us about the visual system. GM /HD /LH
E. What do the psychophysical changes that occur with light adaptation tell us about how the visual system light adapts?
F. What monocular and binocular cues allow us to see depth? JPH
G. Describe the mechanisms of light adaptation. JS
H. Show illusions of colour and explain what they tell us about colour vision. ADR
I. How do we see depth in a random-dot stereograms? SAM
J. How do we encode the direction and speed of motion? PW
K. Why stimuli detected by the luminance and chromatic pathways look so different?
L. Contrast sesnitivity and masking. JH
References
Rodieck, R. W. (1998). The First Steps in Seeing. Sinauer
Kaiser, P. K. and R. M. Boynton (1996). Human Color
Vision, Second Edition. Washington, DC, Optical Society of
America.
Sharpe, L. T et al. (1999). Opsin genes, cone photopigments, color vision and
colorblindness. In Color vision: From Genes to Perception. K. Gegenfurtner and
L. T. Sharpe. Cambridge, Cambridge University Press: 3-51.
Hood, D. C. (1998). Lower-level visual processing and models of light adaptation." Annual Review of
Psychology 49: 503-535.
Any introductory texts on "Sensation and Perception" will cover
topics D and E in some detail. For E, also look for books in the library on
"Visual illusions", of which there are several.
Webvision at http://webvision.med.utah.edu
A. Does activity in the 'dorsal' visual pathway reach
visual awareness? BW
References:
Milner Vision without knowledge. Phil. Trans. R. Soc. Lond., 1997 352: 1249-1256.
Goodale & Milner Separate visual pathways for perception and action Trends in Neuroscience
1992 15: 20-25
B. What is the difference between consciousness and attention? MJ
References:
Crick and Koch Consciousness and Neuroscience Cerebral Cortex 1998 8:97-107.
Lamme Why visual attention and awareness are different. Trends in Cognitive Sciences 2003 7:12-18.
C. What is the 'unit' of attentional selection? AC
References:
Duncan J, Converging levels of analysis in the cognitive neuroscience of visual attention. Phil Trans R Soc Lond B, 1998 353: 1307-1317.
O'Craven KM, Downing PE, & Kanwisher N, fMRI evidence for objects as the units of attentional selection. Nature, 1999 401: 584-587.
D. What is the 'biased competition' theory of attention? MB
References:
Desimone R, Visual attention mediated by biased competition in extrastriate visual cortex. Phil Trans R Soc Lond B, 1998 353: 1245-1255.
Chelazzi L, Miller EK, Duncan J, & Desimone R, Responses of neurons in macaque area V4 during memory-guided visual search. Cereb Cortex, 2001 11: 761-772.
E. What is the 'spotlight' of attention? AR
References:
Brefczynski JA & DeYoe EA, A physiological correlate of the 'spotlight' of visual attention. Nature Neuroscience, 1999 2: 370-374.
Vidyasagar TR, A neuronal model of attentional spotlight: parietal guiding the temporal. Brain Research Reviews, 1999 30: 66-76.
F. What is the 'premotor' theory of attention? AB
References:
Corbetta, M., et al. A common network of functional areas for attention and eye movements. Neuron 21, 761-773 (1998).
Moore, T., Armstrong, K.M. & Fallah, M. Visuomotor origins of covert spatial attention. Neuron 40, 671-683. (2003).
G. What is "blindsight'? SK
References:
Stoerig, P. & Cowey, A. Blindsight in man and monkey. Brain 120, 535-559. (1997).
Weiskrantz, L. Roots of Blindsight. Progress in Brain Research 144, 229-241. (2004).
H. What does the Moon Illusion tell us about size perception? AB
Reference:
Explaining the moon illusion. Kaufman, L. & Kaufman, J.H. (2000) Proc. Natl. Acad. Sci. U. S. A. 97, 500-505
I. What changes in the brain during multistable percepts? PB
Reference:
The neural bases of multistable perception.Sterzer, P., et al (2009). Trends Cogn. Sci. 13, 310-318
J. Does the brain get its wires crossed in visual synaesthesia (e.g., seeing sounds in colour)? GY
References:
Synaesthesia and cortical connectivity.
Bargary, G. & Mitchell, K.J (2008). Trends Neurosci. 31, 335-342
Sound-colour synaesthesia: to what extent does it use cross-modal mechanisms common to us all?
Ward, J., et al (2006). Cortex 42, 264-280
K. How can the brain be fooled by magic? AAG
References:
Attention and awareness in stage magic: turning tricks into research.
Macknik, S.L., et al. (2008). Nat. Rev. Neurosci. 9, 871-879
Towards a science of magic. Kuhn, G., et al. (2008). Trends Cogn. Sci. 12, 349-354
L. Where does the brain learn to read? OV
Reference:
The neural code for written words: a proposal.
Dehaene, S.et al . (2005). Trends Cogn. Sci. 9, 335-341
M. What is the nature of visual brain dysfunction in dyslexia? SP
Reference:
Dyslexia: a deficit in visuo-spatial attention, not in phonological
processing. Vidyasagar, T.R. & Pammer, K (2010). Trends Cogn. Sci. 14, 57-63
Additional attention references:
Kastner S. and Ungerleider L.G. (2001) The neural basis of biased competition in human visual cortex. Neuropsychologia 39, 1263-76
Chun M.M. and Marois R. (2002) The dark side of visual attention. Curr. Opin. Neurobiol. 12, 184-189.
Reynolds J.H. and Chelazzi L. (2004) Attentional modulation of visual processing. Annu. Rev. Neurosci. 27, 611-647
Shipp S. (2004) The brain circuitry of attention. Trends Cogn. Sci. 8, 223-230.
Maunsell JH, Treue S. (2006). Feature-based attention in visual cortex. Trends Neurosci. 29:317-322.
Saalmann YB, Pigarev IN, Vidyasagar TR. 2007. Neural mechanisms of visual attention: how top-down feedback highlights relevant locations. Science. 316:1612-1615.