290 likes | 414 Views
Cortical Fine Timing and Behavior. Yang Yan g Program in Neuroscience, Stony Brook University Zador Lab, Cold Spring Harbor Laboratory Sloan-Swartz Meeting 2010, Yale. Precise stimulus timing can guide behavior. interaural time difference. ∆t ≈ 10 µs. N ot Cortical. 300. 200.
E N D
Cortical Fine Timingand Behavior Yang Yang Program in Neuroscience,Stony Brook University Zador Lab, Cold Spring Harbor Laboratory Sloan-Swartz Meeting 2010, Yale
Precise stimulus timing can guide behavior interaural time difference ∆t ≈ 10 µs Not Cortical
300 200 Neurons in Auditory Cortex can fire precisely in response to sound rat monkey Hromadka, Deweese & Zador, 2008 Barbour &Wang, 2003
Cortical fine timing and behavior • Precise stimulus timing can drive behavior • Not cortical • Sensory stimuli can elicit precisely timed spikes in cortex • behaviorally relevant? • Can precise cortical spike timing drive behavior? • Hard-wired or use-dependent?
Using artificially induced, precisely timed cortical spikes to drive behavior Behavioral paradigm: 2-Alternative Forced Choice task. Dt = 0 LEFT Dt > 0 RIGHT
Using artificially induced, precisely timed cortical spikes to drive behavior Behavioral paradigm: 2-Alternative Forced Choice task. Implant 2 electrodes (A & B, 1.1mm apart) chronically into left auditory cortex,directly stimulate A and B Task: simultaneous A&B vs. B-∆t-A Dt = 0 LEFT Dt > 0 RIGHT
Inter-stimulus Interval (ms) Spike timing of 3 msin auditory cortex can drive behavior! Yang, DeWeese, Otazu, Zador, Nat. Neurosci, 2008
22/24 11/13 6/8 5/7 10/15 1.0 2/7 0.8 Fraction of rats able to perform above chance 0.6 0.4 0/4 0.2 0 100 35 15 7 5 3 1 Inter-stimulus interval (ms) Spike timing of 3 msin auditory cortex can drive behavior Population summary
Spike timing of 3 msin auditory cortex can drive behavior Is auditory cortex unique?
YES: Auditory cortex is different from visual cortex Audition Vision Sunrise, Monet slow fast
Physiology A1 brainmaps.org Hromadka et. al,2005 V1 A1 MT Douglas & Martin, 2004 Buracas et. al, 1998 NO: auditory cortex and visual cortex are similar Canonical Circuit
What about visual cortex? Your guess?
Limit in V1 is 15 ms visual cortex stimulation 4/4 5/5 7/10 2/6 0/7
22/24 11/13 6/8 5/7 10/15 1.0 2/7 0.8 Fraction of rats able to perform above chance 0.6 0.4 0/4 0.2 0 100 35 15 7 5 3 1 Inter-stimulus interval (ms) Visual Cortex is slower than Auditory Cortex Auditory cortex stimulation visual cortex stimulation 4/4 5/5 7/10 2/6 0/7 ** --- A1 --- V1 * Threshold: Auditory cortex: 1-3 ms Visual cortex: 5-15ms ** *: p<0.05 **: p<0.005
Barrel cortex neurons can respond precisely to a whisker stimulation Arabzadeh E. et. al, 2003 How about barrel cortex?
6/6 6/6 6/6 4/6 --- S1 --- A1 --- V1 * * * 0/6 Limit in barrel cortexis 1 ms !
Different cortical areas are different in fine timing discrimination • Thresholds: • Barrel Cortex: 1ms • Auditory Cortex: 3ms • Visual Cortex: 15ms
Audition Vision Whiskers! Sunrise, Monet faster slow fast Hard-wired or use-dependent?
anatomy physiology imaging Fox 1992 Holtmaat & Svoboda, 2009 Glazewski & Fox 1996 Whisker trimming during development changes properties of barrel cortex
Experimental group . . . . . . P0 P60 • Control group: non-deprived P0 P60 • Control group: ipsilateral P0 P60 Sensory Deprivation
Performance is impaired for sensory deprived animals • Median performance for each rat on each Inter-stim-inteval. Barrel control Barrel deprived p<0.05: 3,5,15,35,100 (ms)
Comparing all experimental groups • Median performance for each rat on each Inter-stim-inteval. Error bar: median absolute deviation from the median --- Barrel --- Auditory --- Visual --- Deprived
Performance improved for sensory deprived animals with training y=0.5+(k-0.5)*(1-exp(-t/tau)) k: asymptotic performance, tau: time constant
Tau is bigger for deprived animals than for control animals p=0.0013
Conclusions • The ability to exploit timing information behaviorally is use-dependent • Sensory deprived animals were severely impaired in cortical timing discrimination, suggesting that sensory input during development is essential in establishing the ability of fine timing discrimination in the cortex • Sensory deprived animals showed more improvement with training than the control animals, suggesting that sensory deprived animals could learn to use the cortical timing cue with direct cortical stimulation input
Many thanks to… • Tony Zador • Mike DeWeese • Gonzalo Otazu • Past and present Zadorians • My dear rats yy001-yy293