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Neuroscience_topics
Neuroscience: CNS disease, pain, brain research, ion channels, synaptic transmission, channelopathies, neuronal network
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Scooped by Julien Hering, PhD
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Deficits in Predictive Coding Underlie Hallucinations in Schizophrenia

The neural mechanisms that produce hallucinations and other psychotic symptoms remain unclear. Previous research suggests that deficits in predictive signals for learning, such as prediction error signals, may underlie psychotic symptoms, but the mechanism by which such deficits produce psychotic symptoms remains to be established. We used model-based fMRI to study sensory prediction errors in human patients with schizophrenia who report daily auditory verbal hallucinations (AVHs) and sociodemographically matched healthy control subjects. We manipulated participants' expectations for hearing speech at different periods within a speech decision-making task. Patients activated a voice-sensitive region of the auditory cortex while they experienced AVHs in the scanner and displayed a concomitant deficit in prediction error signals in a similar portion of auditory cortex. This prediction error deficit correlated strongly with increased activity during silence and with reduced volumes of the auditory cortex, two established neural phenotypes of AVHs. Furthermore, patients with more severe AVHs had more deficient prediction error signals and greater activity during silence within the region of auditory cortex where groups differed, regardless of the severity of psychotic symptoms other than AVHs. Our findings suggest that deficient predictive coding accounts for the resting hyperactivity in sensory cortex that leads to hallucinations. (...) -  by Horga et al., The Journal of Neuroscience, 11 June 2014, 34(24): 8072-8082

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Scooped by Julien Hering, PhD
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Scientists construct first map of how the brain organizes everything we see

Scientists construct first map of how the brain organizes everything we see | Neuroscience_topics | Scoop.it

Our eyes may be our window to the world, but how do we make sense of the thousands of images that flood our retinas each day? Scientists at the University of California, Berkeley, have found that the brain is wired to put in order all the categories of objects and actions that we see. They have created the first interactive map of how the brain organizes these groupings. (...) - By Yasmin Anwar, Media Relations UC Berkeley News Center, December 19, 2012 

Julien Hering, PhD's insight:

Here's the interactive map: http://gallantlab.org/semanticmovies/


More about this: http://www.newscientist.com/article/mg21728984.400-take-a-peek-inside-the-brains-filing-cabinet.html

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Emre Erdogan's curator insight, March 12, 2013 2:14 AM

Concepts and our brain