Thursday, April 17, 2014

higher-level cortical areas

Neural portraits of perception: Reconstructing face images from evoked brain activity
Volume 94, 1 July 2014, Pages 12–22

What if you could "see" if your partner was cheating on you and with whom?
What  if could see your colleague's bright idea that might get he or she and not you promoted ?

What if you could see someone's fingers enter their pin number on a Mac machine?
What if you could see  inside someone else's dreams?

Recent neuroimaging advances have allowed visual experience to be reconstructed from patterns of brain activity.
 While neural reconstructions have ranged in complexity, they have relied almost exclusively on retinotopic mappings between visual input and activity in early visual cortex.

 However, subjective perceptual information is tied more closely to higher-level cortical regions that have not yet been used as the primary basis for neural reconstructions.

 Furthermore, no reconstruction studies to date have reported reconstructions of face images, which activate a highly distributed cortical network. Thus, we investigated
 (a) whether individual face images could be accurately reconstructed from distributed patterns of neural activity, and
 (b) whether this could be achieved even when excluding activity within occipital cortex. Our approach involved four steps.
(1) Principal component analysis (PCA) was used to identify components that efficiently represented a set of training faces.
(2) The identified components were then mapped, using a machine learning algorithm, to fMRI activity collected during viewing of the training faces
(3) Based on activity elicited by a new set of test faces, the algorithm predicted associated component scores.
(4) Finally, these scores were transformed into reconstructed images.

 Using both objective and subjective validation measures, we show that our methods yield strikingly accurate neural reconstructions of faces even when excluding occipital cortex. This methodology not only represents a novel and promising approach for investigating face perception, but also suggests avenues for reconstructing ‘offline’ visual experiences—including dreams, memories, and imagination—which are chiefly represented in higher-level cortical areas.

 there was a need
to know\not only
what one was thinking

at any given moment
in the day

had a vested interest in
how A Mind Works
how a Mind responds to any number of stimuli

the problem was
that was

that  the Human Guinea Pigs  involved in the  studies

began responding
quite like genuine Guinea Pigs eventually did 

Guinea pigs

 stop eating
 refuse to move from the side of the cage
they become unresponsive to handling
or participation in false stimuli
and seem to innately remember that before the word "GUINEA PIG"
meant "Guinea Pig"as we often define the term 

for either animal or human testing
          they are guinea pigs
and would rather die
as such-

than BE guinea pigs

Full-size image (31 K)

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