Multiprobe multiple single-unit recordings and visual information processing in the primate brain Hiroshi TAMURA V2 V1 V4 TEO TE Saturday, March 5, 2011
Gallant et al 1996 Ito & Komatsu 2004 TE V4 V2 V4 TE Tamura &Tanaka 2001 Desimone et al 1984 Stimulus-selective responses of neurons in visual cortices V2 V1 V4 TEO TE Saturday, March 5, 2011
Tamura &Tanaka 2001 A neuron in the inferior temporal (IT) cortex responded to an image of a chair 2.0 5.0 27.8 Saturday, March 5, 2011
How are the selective responses of IT neurons generated ? How are the neurons involved in the representation of visual images distributed in the IT cortex ? Saturday, March 5, 2011
Functional neuronal circuitry in the inferior temporal (IT) cortex Saturday, March 5, 2011
Heptode (Thomas) Multiprobe recording allows us to record simultaneously from multiple single neurons, and to perform cross-correlation analysis of spike trains Saturday, March 5, 2011
Signals recorded with Heptode Signals from 6 of the 7 recording probes were shown Saturday, March 5, 2011
Kaneko et al. 1999, 2007 Time cell 1 cell 2 cell n : Spike detection Spike classification Spike trains Isolation and classification of spikes 3 1 5 2 4 Saturday, March 5, 2011
Recording and visual stimulus presentation system Saturday, March 5, 2011
trail 1 0 trail 2 5 10 15 20 25 30 -t cell 2 +t 0 -t +t Time (reference) (reference) R 0 cell 1 5 trail 3 trail 4 trail 5 cell 1 cell 2 trail 5 0 R 10 15 20 25 30 trail 1 trail 2 trail 3 trail 4 Estimate functional connectivity with cross-correlation analysis raw correlograms shift predictors (trials were shifted for each stimulus condition) Saturday, March 5, 2011
inhibitory target neuron excitatory (cell 2) neuron target (cell 1) neuron neuron (cell 4) Raw correlogram Shift predictor (control) Raw correlogram Shift predictor (control) cell 3 -> cell 4 cell 1 -> cell 2 cell 4 -> cell 3 (cell 3) cell 2 -> cell 1 Inhibitory and excitatory interactions between neurons in the IT cortex Cell 2 -> Cell 1 Cell 1 -> Cell 2 250 250 Spikes/bin 0 0 -0.1 0 0.1 Time (s) Cell 2 -> Cell 1 Cell 1 -> Cell 2 200 200 Spikes/bin 0 0 -0.04 0 0.04 Time (s) Saturday, March 5, 2011
Signal correlation Tamura et al. 2003, 2004 A Inhibitory interactions Cell 2 -> Cell 1 Cell 1 -> Cell 2 250 250 were found in neuron pairs Spikes/bin with negatively correlated stimulus preferences 0 0 0 -0.1 0.1 Time (s) B 30 Cell 1 Spikes/s 0 -20 10 Cell 2 Spikes/s 0 -15 1 Stimulus 67 Saturday, March 5, 2011
Signal correlation Excitatory interactions were found in neuron pairs with positively correlated stimulus preferences A Cell 2 -> Cell 1 Cell 1 -> Cell 2 200 200 Spikes/bin 0 0 -0.04 0 0.04 Time (s) B Cell 4 -> Cell 3 Cell 3 -> Cell 4 200 200 Spikes/bin 0 0 -0.02 0 0.02 Time (s) Saturday, March 5, 2011
Inhibitory interaction Excitatory interaction Tamura et al. 2003, 2004 In the inferior temporal cortex, inhibitory interactions exist between neurons with different stimulus preferences Saturday, March 5, 2011
Recording sites Cell 55 neurons (1485 pairs) The best stimuli of Normalized center peak height Cell * #$)' #(!& Vertical connections # !") (() ! !&% "%%(') % $)* ('& " '' "(& $ ('#%$" Cross-correlation ) !# !%)$$ $&")" '""#$! ' $!' ( #%' & %%" #*!*) "#'#%$ #* $"$ ## $& !"( #**$ #! " %%"(( !&#!") &#)&!' #% !!$( ('*& #" '" #$ #%& !"'$) #) ! #' #( $% !!%& #& ")*'( !* &" $))!"' '"(%*% !# !! #') !(! !*((! !% !" !$ !)# !) ##)"! &$("&' Most of the functional !' !$# interactions were observed in !( !(%!# !& "($()( adjacent neuron pairs %* ##( #"%$$ &$#&!) %# $!&! Saturday, March 5, 2011
25 0 19 7k 1 9 15 302 0 1 17 28 18k 52k 2 4 0 15 32 4k 51k 200805271733 (28 cells => 378 pairs) Shank-1 Shank-2 Shank-3 Shank-4 Shank-5 Shank-6 Shank-7 Shank-8 15 0 1 0 16k 24 9 16k 15k 0 1 0 19 7k 1 9 15 302 0 1 17 28 15k 25 24 9 0 51k 4k 32 4 0 2 52k 18k Horizontal connections We found short-range and long-range horizontal connections Saturday, March 5, 2011
Inhibitory interaction Excitatory interaction Tamura et al. 2003, 2004 In the inferior temporal cortex, inhibitory interactions exist between neurons with different stimulus preferences Saturday, March 5, 2011
Representation of visual object information in the inferior temporal (IT) cortex Saturday, March 5, 2011
How wide is necessary? widely distributed? or locally distributed? Saturday, March 5, 2011
“The representations are widely distributed ” Haxby et al., Science 293:2425-2430, 2001 Saturday, March 5, 2011
Complex objects are represented by combinations of feature columns 1 mm Tsunoda et al., Nat Neurosci 4:832-838, 2001 Saturday, March 5, 2011
Adjacent neurons belong to independent networks Yoshimura et al., Nature 433:868-873, 2005 Saturday, March 5, 2011
Tamura et al. 2005 TE 下側頭葉 Responses of 3 adjacent neurons to a stimulus set 1 ch 2 ch 3 ch 4 ch 5 ch 6 ch cell 1 cell 2 0.2 cell 3 mv -0.2 0 1.5 ms A Cell 1 B Cell 2 C Cell 3 65 67.5 80 1s 1s 1s 0 0 0 40 60 40 Spikes/s Spikes/s Spikes/s 0 0 0 1 64 1 64 1 64 Saturday, March 5, 2011
Adjacent neurons do not always share stimulus preferences Neurosci Res 52:311-322, 2005 Saturday, March 5, 2011
How wide is necessary? We investigated this issue by quantifying single-trial responses with a linear decoding analysis Saturday, March 5, 2011
I am sorry, I removed 2nd part of my talk Saturday, March 5, 2011
The representation is locally distributed Saturday, March 5, 2011
Cell Time (sec) 0 50 Spike trains of 55 simultaneously recorded neurons Saturday, March 5, 2011
Collaboration between computational neuroscientists and neurophysiologists (biologists) spike trains from multiple neurons http://images.jsc.nasa.gov/lores/S68-49301.jpg Saturday, March 5, 2011
Recommend
More recommend
