here is a nice opinion piece in NRN on the role noise plays in information processing.
The benefits of noise in neural systems: bridging theory and experiment.
McDonnell & Ward
Thursday, June 23, 2011
Monday, June 20, 2011
Thursday, June 16, 2011
in this week's Nature
Control of visual cortical signals by prefrontal dopamine
Noudoost & Moore
ABSTRACT The prefrontal cortex is thought to modulate sensory signals in posterior cortices during top-down attention, but little is known about the underlying neural circuitry. Experimental and clinical evidence indicate that prefrontal dopamine has an important role in cognitive functions, acting predominantly through D1 receptors. Here we show that dopamine D1 receptors mediate prefrontal control of signals in the visual cortex of macaques (Macaca mulatta). We pharmacologically altered D1-receptor-mediated activity in the frontal eye field of the prefrontal cortex and measured the effect on the responses of neurons in area V4 of the visual cortex. This manipulation was sufficient to enhance the magnitude, the orientation selectivity and the reliability of V4 visual responses to an extent comparable with the known effects of top-down attention. The enhancement of V4 signals was restricted to neurons with response fields overlapping the part of visual space affected by the D1 receptor manipulation. Altering either D1- or D2-receptor-mediated frontal eye field activity increased saccadic target selection but the D2 receptor manipulation did not enhance V4 signals. Our results identify a role for D1 receptors in mediating the control of visual cortical signals by the prefrontal cortex and suggest how processing in sensory areas could be altered in mental disorders involving prefrontal dopamine.
Noudoost & Moore
ABSTRACT The prefrontal cortex is thought to modulate sensory signals in posterior cortices during top-down attention, but little is known about the underlying neural circuitry. Experimental and clinical evidence indicate that prefrontal dopamine has an important role in cognitive functions, acting predominantly through D1 receptors. Here we show that dopamine D1 receptors mediate prefrontal control of signals in the visual cortex of macaques (Macaca mulatta). We pharmacologically altered D1-receptor-mediated activity in the frontal eye field of the prefrontal cortex and measured the effect on the responses of neurons in area V4 of the visual cortex. This manipulation was sufficient to enhance the magnitude, the orientation selectivity and the reliability of V4 visual responses to an extent comparable with the known effects of top-down attention. The enhancement of V4 signals was restricted to neurons with response fields overlapping the part of visual space affected by the D1 receptor manipulation. Altering either D1- or D2-receptor-mediated frontal eye field activity increased saccadic target selection but the D2 receptor manipulation did not enhance V4 signals. Our results identify a role for D1 receptors in mediating the control of visual cortical signals by the prefrontal cortex and suggest how processing in sensory areas could be altered in mental disorders involving prefrontal dopamine.
Wednesday, June 15, 2011
Codes and representations
A friend sent me this paper yesterday, and although its 10 years old, its a very nicely written piece on the relationship between neural codes and representations.
Saturday, June 11, 2011
Women in Science
Here is an interesting piece in NYT on women in science. 4 top women scientists discuss the challenges they faced in rising through the ranks and in their respective fields.
Thursday, June 9, 2011
Check out these new papers in Nature Neuro
A normalization model of multi sensory integration
Oshiro, Agelaki and DeAngelis
News & Views by Churchland
Transitions in neural oscillations reflect prediction errors generated in audiovisual speech.
Arnal, Wyart & Giraud
News & Views by Chandrasekaran & Ghazanfar
Oshiro, Agelaki and DeAngelis
News & Views by Churchland
Transitions in neural oscillations reflect prediction errors generated in audiovisual speech.
Arnal, Wyart & Giraud
News & Views by Chandrasekaran & Ghazanfar
Monday, June 6, 2011
New Serences Lab paper in TICS
Reciprocal relations between cognitive neuroscience and formal cognitive models: opposites attract?
Forstmann, Wagenmakers, Eichle, Brown and Serences
Forstmann, Wagenmakers, Eichle, Brown and Serences
SFN comments on the new Lab Animal Guide
The new lab animal guide being proposed would have a significant, and potentially negative, effect on laboratory research. In this statement by SFN, they correctly point out that many of the proposed new guidelines are not founded on any data.
Read their full statement here
Read their full statement here
Thursday, June 2, 2011
UCSD Symposium on Neural Computation
Joint Symposium on Neural Computation
Date: Saturday, June 4, 9:00 am - 5:30 pm
Location: Institute for Neural Computation, UCSD, La Jolla, CA
Directions: http://www.jsnc.caltech.edu/directions.html
Conference Program and Posters: http://www.jsnc.caltech.edu/index.html
Sponsored by Qualcomm and Brain Corporation
Keynote Talks:
Kwabena Boahen, Stanford
Toby Berger, University of Virginia
-----
SESSION 1: Vision
Chair: Charles Chubb, UCI
9:00 am - Nuno Vasconcelos, UCSD
"Discriminant saliency networks"
9:30 am - Alyssa Brewer, UCI
"Functional Plasticity in Human Parietal Cortex:
Adapting to Reversed Visual Input"
10:00 am - break
SESSION 2: Sensorimotor Control
Chair: Bosco Tjan, USC
10:15 am - Stefan Schaal, USC
"Path Integral Reinforcement Learning for Motor Skills"
10:45 am - Tansu Celikel, USC
"Closed loop sensorimotor computation for haptic object localization"
11:15 am - break
11:30 am - Keynote Talk
Chair: Gert Cauwenberghs, UCSD
Kwabena Boahen, Stanford
"Emulating a million neurons in the cortex"
12:30 pm Poster Spotlights
1:00 pm Lunch
SESSION 3: Neural Dynamics
Chair: Mayank Mehta, UCLA
2:00 pm - Dean Buonomano, UCLA
"Telling Time with Neural Dynamics"
2:30 pm - Khaleel Razak, UCR
"Neural mechanisms underlying FM sweep selectivity in the auditory cortex"
3:00 pm - break
SESSION 4: Neural Systems
Chair: Thanos Siapas, Caltech
3:15 pm - Tanya Sharpee, Salk
"Minimal models of multidimensional neural computations"
3:45 pm - Pietro Perona, Caltech
"The multidimensional wisdom of crowds"
4:15 pm - break
4:30 pm - Keynote Talk
Chair: Terry Sejnowski
Toby Berger, University of Virginia
"Neurons as Finite-State Channels with Feedback"
5:30 pm - Closing Remarks - Terry Sejnowski
46 Posters: http://www.jsnc.caltech.edu/program.html
-----
Registration fee: $35. Payable at the door by cash or by check made out
to UC Regents. Registration fee includes lunch and refreshments.
Date: Saturday, June 4, 9:00 am - 5:30 pm
Location: Institute for Neural Computation, UCSD, La Jolla, CA
Directions: http://www.jsnc.caltech.edu/directions.html
Conference Program and Posters: http://www.jsnc.caltech.edu/index.html
Sponsored by Qualcomm and Brain Corporation
Keynote Talks:
Kwabena Boahen, Stanford
Toby Berger, University of Virginia
-----
SESSION 1: Vision
Chair: Charles Chubb, UCI
9:00 am - Nuno Vasconcelos, UCSD
"Discriminant saliency networks"
9:30 am - Alyssa Brewer, UCI
"Functional Plasticity in Human Parietal Cortex:
Adapting to Reversed Visual Input"
10:00 am - break
SESSION 2: Sensorimotor Control
Chair: Bosco Tjan, USC
10:15 am - Stefan Schaal, USC
"Path Integral Reinforcement Learning for Motor Skills"
10:45 am - Tansu Celikel, USC
"Closed loop sensorimotor computation for haptic object localization"
11:15 am - break
11:30 am - Keynote Talk
Chair: Gert Cauwenberghs, UCSD
Kwabena Boahen, Stanford
"Emulating a million neurons in the cortex"
12:30 pm Poster Spotlights
1:00 pm Lunch
SESSION 3: Neural Dynamics
Chair: Mayank Mehta, UCLA
2:00 pm - Dean Buonomano, UCLA
"Telling Time with Neural Dynamics"
2:30 pm - Khaleel Razak, UCR
"Neural mechanisms underlying FM sweep selectivity in the auditory cortex"
3:00 pm - break
SESSION 4: Neural Systems
Chair: Thanos Siapas, Caltech
3:15 pm - Tanya Sharpee, Salk
"Minimal models of multidimensional neural computations"
3:45 pm - Pietro Perona, Caltech
"The multidimensional wisdom of crowds"
4:15 pm - break
4:30 pm - Keynote Talk
Chair: Terry Sejnowski
Toby Berger, University of Virginia
"Neurons as Finite-State Channels with Feedback"
5:30 pm - Closing Remarks - Terry Sejnowski
46 Posters: http://www.jsnc.caltech.edu/program.html
-----
Registration fee: $35. Payable at the door by cash or by check made out
to UC Regents. Registration fee includes lunch and refreshments.
Wednesday, June 1, 2011
check out these new reviews in TICS
Understanding complexity in the human brain
Danielle Bassett and Michael Gazzaniga
The neural variability of inter-temporal decision-making: understanding variability
Jan Peters and Christian Buchel
Danielle Bassett and Michael Gazzaniga
The neural variability of inter-temporal decision-making: understanding variability
Jan Peters and Christian Buchel
new book review
Nicolas Humphrey's new book 'Soul Dust: The Magic of Consciousness' gets reviewed in Science. Proulx makes a number of parallels with Crick in the review. Check it out
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