Thursday, October 28, 2010
here is a review in Nature:
here is the Amazon synopsis:
In "Musicophilia", Oliver Sacks explored music and the brain; now, in "The Mind's Eye", he writes about the myriad ways in which we experience the visual world: how we see in three dimensions; how we recognize individual faces or places; how we use language to communicate verbally; how we translate marks on paper into words and paragraphs; and, even how we represent the world internally when our eyes are closed. Alongside remarkable stories of people who have lost these abilities but adapted with courage, resilience and ingenuity, there is an added, personal element: one day in late 2005, Sacks became aware of a dazzling, flashing light in one part of his visual field; it was not the familiar migraine aura he had experienced since childhood, and just two days later a malignant tumor in one eye was diagnosed. In subsequent journal entries - some of which are included in "The Mind's Eye" - he chronicled the experience of living with cancer, recording both the effects of the tumor itself, and radiation therapy. In turning himself into a case history, Sacks has given us perhaps his most intimate, impressive and insightful (no pun intended) book yet.
Wednesday, October 27, 2010
get more info here: http://www.aronlab.org/Site/Workshop.html
Tuesday, October 26, 2010
Monday, October 25, 2010
Howard Hughes Investigator
Professor of Neurobiology at the University of California, Berkeley
"Neuromodulation of brain state"
Tuesday, October 26th
CNCB Large Conference Room (formerly CMG)
Professor Yang Dan is a Howard Hughes Investigator and Professor of
Neurobiology at the University of California, Berkeley. Her work
focuses on how visual information is encoded and processed by cortical
circuits, and how the dynamics of these processes changes with
experience and across brain states. To probe these questions, her
laboratory applies a wide range of techniques, including
electrophysiology, imaging, pharmacology, behavioral paradigms, and
Friday, October 22, 2010
'Adaptive reorganization of the tonotopic map in A1'
Functional property of the brain changes in accommodation to experience. The extent of experience-induced changes in adult brain has been shown, however, to be largely limited. Our studies demonstrated that the primary auditory cortex (AI) underwent large-scale reorganization in adult rats exposed to low-level ambient noises, resulting in transformation of a tonotopic to a clustered representation of sound frequencies. Further behavioral studies demonstrated that, in the absence of the tonotopic map, auditory instrumental learning was slowed down only mildly but fine pitch discrimination was impaired severely. Finally, when tested in a noisy environment, the noise-exposed rats performed much better than the normal rats in a learned task of sound pattern recognition. These results suggest that the topographic representation of sound frequencies in AI is necessary for fine, but not for coarse, pitch discrimination and can be optimized adaptively to acoustic experience in a large-scale even in adult rats.
Monday, October 18, 2010
The effects of electrical microstimulation on cortical signal propagation
Nikos K Logothetis, Mark Augath, Yusuke Murayama, Alexander Rauch, Fahad Sultan, Jozien Goense, Axel Oeltermann & Hellmut Merkle
The authors use combined electrostimulation, neurophysiology, microinjection and fMRI to show that stimulation of a site in the lateral geniculate nucleus of monkeys increases fMRI signals in regions of primary visual cortex, but suppresses it in retinotopically matched regions of extrastriate cortex. Their results suggest that electrostimulation disrupts cortico-cortical signal propagation by silencing the output of any neocortical area whose afferents are electrically stimulated.
'Discovering functional systems in the ventral visual stream'
Selectivity for faces, places, and bodies feature prominently in the literature on the ventral visual pathway. Are face, place, and body selectivity in fact the most robust and dominant response profiles in this region, or are they merely three among a much wider set of category-selective (and other) response profiles? Here we use a hypothesis-neutral structure discovery method that avoids the assumptions built into most past work by i) giving equal consideration to all possible response profiles over the conditions tested, ii) relaxing implicit anatomical constraints (that important functional profiles should be manifest in spatially contiguous voxels, and in a similar locations across subjects), and iii) testing for dominant response profiles over images, rather than categories, thus enabling us to discover rather than presume the categories respected by the brain. Even with these assumptions relaxed, face, place, and body selectivity emerge as dominant in the ventral stream.