Causal inference:

 

http://www.cell.com/trends/cognitive-sciences/abstract/S1364-6613%2810%2900147-6

 

suggested by Elfi

Face-Identity Change Activation Outside the Face System: "Release from Adaptation" May Not Always Indicate Neuronal Selectivity

 

Feed: Cerebral Cortex - current issue
Posted on: dinsdag 17 augustus 2010 23:46
Author: Mur, M., Ruff, D. A., Bodurka, J., Bandettini, P. A., Kriegeskorte, N.
Subject: Face-Identity Change Activation Outside the Face System: "Release from Adaptation" May Not Always Indicate Neuronal Selectivity

 

Face recognition is a complex cognitive process that requires distinguishable neuronal representations of individual faces. Previous functional magnetic resonance imaging (fMRI) studies using the "fMRI-adaptation" technique have suggested the existence of face-identity representations in face-selective regions, including the fusiform face area (FFA). Here, we present face-identity adaptation findings that are not well explained in terms of face-identity representations. We performed blood-oxygen level–dependent (BOLD) fMRI measurements, while participants viewed familiar faces that were shown repeatedly throughout the experiment. We found decreased activation for repeated faces in face-selective regions, as expected based on previous studies. However, we found similar effects in regions that are not face-selective, including the parahippocampal place area (PPA) and early visual cortex (EVC). These effects were present for exact-image (same view and lighting) as well as different-image (different view and/or lighting) repetition, but more widespread for exact-image repetition. Given the known functional properties of PPA and EVC, it appears unlikely that they contain domain-specific face-identity representations. Alternative interpretations include general attentional effects and carryover of activation from connected regions. These results remind us that fMRI stimulus-change effects can have a range of causes and do not provide conclusive evidence for a neuronal representation of the changed stimulus property.

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Suggested by Maarten

FW: Imaging retinotopic maps in the human brain

 

 

Feed: ScienceDirect Publication: Vision Research
Posted on: 07 August 2010 21:52
Author: ScienceDirect Publication: Vision Research
Subject: Imaging retinotopic maps in the human brain

 

Publication year: 2010 Source: Vision Research, In Press, Accepted Manuscript, Available online 6 August 2010 Brian A., Wandell , Jonathan, Winawer A quarter-century ago visual neuroscientists had little information about the number and organization of retinotopic maps in human visual cortex. The advent of functional magnetic resonance imaging (MRI), a non-invasive, spatially-resolved technique for measuring brain activity, provided a wealth of data about human retinotopic maps. Just as there are differences amongst nonhuman primate maps, the human maps have their own unique properties. Many human maps can be measured reliably in individual subjects during experimental sessions lasting less than an hour. The efficiency of the measurements and the relatively large amplitude of functional MRI signals in visual cortex make it possible...

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FW: Computing moment to moment BOLD activation for real-time neurofeedback

 

 

Feed: ScienceDirect Publication: NeuroImage
Posted on: 03 August 2010 21:25
Author: ScienceDirect Publication: NeuroImage
Subject: Computing moment to moment BOLD activation for real-time neurofeedback

 

Publication year: 2010 Source: NeuroImage, In Press, Accepted Manuscript, Available online 2 August 2010 Oliver, Hinds , Satrajit, Ghosh , Todd W., Thompson , Julie J., Yoo , Susan, Whitfield-Gabrieli , ... Estimating moment to moment changes in blood oxygenation level dependent (BOLD) activation levels from functional magnetic resonance imaging (fMRI) data has applications for learned regulation of regional activation, brain state monitoring, and brain-machine interfaces. In each of these contexts, accurate estimation of the BOLD signal in as little time as possible is desired. This is a challenging problem due to the low signal-to-noise ratio of fMRI data. Previous methods for real-time fMRI analysis have either sacrificed the ability to compute moment to moment activation changes by averaging several acquisitions into a single activation estimate or have sacrificed accuracy by failing...

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Imaging retinotopic maps in the human brain

Publication year: 2010 Source: Vision Research, In Press, Accepted Manuscript, Available online 6 August 2010 Brian A., Wandell , Jonathan, Winawer A quarter-century ago visual neuroscientists had little information about the number and organization of retinotopic maps in human visual cortex. The advent of functional magnetic resonance imaging (MRI), a non-invasive, spatially-resolved technique for measuring brain activity, provided a wealth of data about human retinotopic maps. Just as there are differences amongst nonhuman primate maps, the human maps have their own unique properties. Many human maps can be measured reliably in individual subjects during experimental sessions lasting less than an hour. The efficiency of the measurements and the relatively large amplitude of functional MRI signals in visual cortex make it possible...

View article...

Article suggested by Maarten