Methods We analyzed spinal fMRI data from healthy subjects during a proprioceptive and a tactile stimulation by using two model-based approaches, i.e., CC analysis between the stimulus shape and the time
course of every voxel, and the GLM. Moreover, we applied independent component analysis, a model-free approach which decomposes the data in a set of source signals.
Results All methods were able to detect cervical cord areas of activity corresponding to the expected regions of neuronal activations. Model-based approaches (CC and GLM) revealed find more similar patterns of activity. ICA could identify a component correlated to fMRI stimulation, although with a lower statistical threshold than model-based approaches, and many components, consistent across subjects, which are likely to be secondary
Salubrinal cell line to noise present in the data.
Conclusions Model-based approaches seem to be more robust for estimating task-related activity, whereas ICA seems to be useful for eliminating noise components from the data. Combined use of ICA and GLM might improve the reliability of spinal fMRI results.”
“Remembering where things are – object-location memory – is essential for daily-life functioning. Functionally, it can be decomposed into at least three distinct processing mechanisms: (a) object processing, (b) spatial-location processing and (c) object to location binding. A neurocognitive model is sketched, which posits a mostly bilateral ventral cortical network supporting object-identity
memory, a left fronto-parietal circuit for categorical position processing and working memory aspects, and a right fronto-parietal circuit for coordinate position processing and working memory. Medial temporal lobes and in particular the hippocampus appear essential for object-location binding. It is speculated that categorical object-location binding and episodic memory binding in general depend more on the left-sided areas, whereas coordinate object-location processing and navigation in large scale space involve the right-sided counterparts. isometheptene The various object-location memory components differ in the extent to which they are automatized or require central effort. While automatic routines protect against brain damage, neural deficits might potentially also lead to a shift upon the automatic-effortful continuum. (c) 2008 Elsevier Ltd. All rights reserved.”
“The objective of this review is to examine and evaluate recent findings on cognitive functioning (in particular imagery processes) in individuals with congenital visual impairments, including total blindness, low-vision and monocular vision. As one might expect, the performance of blind individuals in many behaviours and tasks requiring imagery can be inferior to that of sighted subjects; however, surprisingly often this is not the case.