KNIGHT, Robert, ECoG, Cortical Recording, Cal Berkeley, Dec 4, 2017
<p class="MsoNormal" >KNIGHT, Robert, ECoG, Cortical Recording, Cal Berkeley, Dec 4, 2017
this is an MBC Monday 5:10PM seminar in Math Corner at Stfd
in the Monday series.
Bob Knight is a neurologist, does rsch at Helen Wills Neurosci
at Cal, Berk.
full title is <b>Insights into Human Cognition from Direct Brain Recording</b>...
intracranial recording...
David Ferrier in 1876 cut off frontal lobes of his 3 smartest monkeys.
then on to A R Luria and Frontal Cortex.
1973: The Working Brain (first pub in sixties.
quite brilliant and prescient.
tumor or trauma (and also frontal dementia and hemorrhage , etc)
social interactions orbitofrontal
Ferrier 1876... lost faculty of attentive and intelligent observation
and 1973 Luria...; and grasping reflex
pursues lips... snout reflex
locked into the present... lateral frontal patient (lose IQ)
as distinct from orbitofrontal... lose social interaction...
BA 10, 11, 12, 13, 14, 47.
video of pt with orbitofrontal damage...
1929 scalp EEG Hans Berger...
Fourier 1768 to 1830...
he calls HFB high freq band above 65 Hz. high gamma...
low gamma 30 to 65.
this reflects single spike activity... signature of cortical activation...
epilepsy = 1% of the population of entire planet (excluding febrile sz)
450K people have uncontrolled sz in USA.
surgery for epilepsy...
1/3 of cases; we record from 5 med centers.
1/3 of cases... need depth trodes... into HC = hippocampus or OFC or cingulate, etc.
bilat amygdala, bilat HC, bilat insula, etc.
can push out microwires to see single unit spikes.
end of preamble *
this is TICS 2016 Helfrich and Knight...
287 patients ... we have recording (but 1 in 5 patients cannot get data)
high freq band tracks behavior (70 to 200 Hz)
Working Memory by Eddie Chang in J Cog Neuro in 2011.
listen to phonemes, eg LUL (lool or LUL) compare present to
2 back.
ie zero back to 2-back.
hear the word, implement the rule and press the button...
watch the activity go from super temp (auditory) to frontal lobe to motor cortex.
Lisa Johnson study in Cur Bio in 2017.
theta originates in PFC and goes to poster brain...
alpha goes in opposite direciton (from back to front)
video of Broca's aphasia.
non fluent aphasia... he can understand the content and can formulate the answer.
big program ... Carquinez VA...
she has patient Tan's brain (the original brain studied by Broca)
pars triangularis and pars... destroy those and only aphasic for one week!
ball... bounce;
verb generation study... he says BALL; S says hit, eg.
Auditory perhaps 300 to 500 msec. in super temp gyrus.
when you speak, Broca's area shut's off!! it's artic planning (not speech)
how abt the HC = hippocampus?
HC theta tracks semantics...
when constrained by context... eg he opened the door with the key.
HC involved in extracting meaning from sentence.
theta builds up....
*
Ryan Canolty in Scence 2006...
brain gets into synch in 100 msec.
trough of theta... get spiking activity...
theta-HFB coupling occurs.
phase of theta (a dip in theta) assoc with incr. high gamma.
when attending to a hemifield... get coupling of front and back of brain PFC and IPS.
phase amplitude coupling... assoc with high freq. high gamma)
next PFC theta drives motor cortex HFB = high freq. band.
(brad voytek... his work... just got tenure)
how about emotion....
theta amygd drives the HC HEAD (but not in the tail of the HC)
the amygdala drives the HC !!!! every subject
also confirmed with Granger causality.
next... 16 subjects; 8 tasks; and 38 ECoG sessions...
huge r2 = 93% for sustained frontal activity when it decays versus when
motor spking increases and they cross... that crossing predicts RT.
current grids are 3 mm center on...
next... categorical perception...
bah vs gah vs dah... automatic at 120 msec.
languageplasticity...
plays noisy sentence... cannot understand it...
then play the sentence in PLAIN... then noisy again (and it's now comprehensible)
works in a couple of seconds...
Brian Pasley... in 2012 PLoS Bio.
he does speech replayed from the brain (similar to work with images)
can you decode internal discourse.
imagine talking...
Gettysburg address.
four score and seven years ago our fathers brought forth on this continent...
and now imagine saying it...
stephanie Martin... we can decode imagined speech.
trodes in STG and ST sulcus.
he likes Pink Floyd...
Bellier research...
Pink Floyd playback from brain ...
15 year old... freshman at Cal Berk.
would get UCSF neurosurg...
he practiced two classical pieces....
played piece but just imagined the music...
huge lab... shows 2 dozen students in intracranial team...
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