The brain as a flexible task machine

Department of Medical Neurobiology, The Institute for Medical Research Israel-Canada, Israel.
Current opinion in neurology (Impact Factor: 5.31). 12/2011; 25(1):86-95. DOI: 10.1097/WCO.0b013e32834ed723
Source: PubMed


The exciting view of our brain as highly flexible task-based and not sensory-based raises the chances for visual rehabilitation, long considered unachievable, given adequate training in teaching the brain how to see. Recent advances in rehabilitation approaches, both noninvasive, like sensory substitution devices (SSDs) which present visual information using sound or touch, and invasive, like visual prosthesis, may potentially be used to achieve this goal, each alone, and most preferably together.
Visual impairments and said solutions are being used as a model for answering fundamental questions ranging from basic cognitive neuroscience, showing that several key visual brain areas are actually highly flexible, modality-independent and, as was recently shown, even visual experience-independent task machines, to technological and behavioral developments, allowing blind persons to 'see' using SSDs and other approaches.
SSDs can be potentially used as a research tool for assessing the brain's functional organization; as an aid for the blind in daily visual tasks; to visually train the brain prior to invasive procedures, by taking advantage of the 'visual' cortex's flexibility and task specialization even in the absence of vision; and to augment postsurgery functional vision using a unique SSD-prostheses hybrid. Taken together the reviewed results suggest a brighter future for visual neuro-rehabilitation.

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Available from: Amir Amedi
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    • "Alternatives to the tactile approach include encoding visual information into audible signals (Capelle et al., 1998; Hanneton et al., 2010; Loomis, 2010; Meijer, 1992). Such devices have shown great promise, however their uptake has been limited and development is ongoing (Loomis, 2010; Reich et al., 2012). "
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    • "l and Collignon , 2011 ) . For example , despite a reorientation in modality tuning , the visually deprived occipital cortex of early - blind individuals seems to maintain a division of computational labor somewhat similar to the one characterizing the sighted brain ( Amedi et al . , 2005 ; Collignon et al . , 2009a ; Dormal and Collignon , 2011 ; Reich et al . , 2012 ; Ricciardi et al . , 2013 ) . Functionally selective crossmodal recruitment has been demonstrated for several cognitive functions , such as the ability to recognize the shape of an object involving the recruitment of the lateral occipital cortex ( LOC / LOtv ; audition : Amedi et al . , 2007 ; touch : Pietrini et al . , 2004 ; Amedi et"
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    ABSTRACT: One of the most striking demonstrations of experience-dependent plasticity comes from studies of sensory deprived individuals (e.g., blind or deaf), showing that brain regions deprived of their natural inputs change their sensory tuning to support the processing of inputs coming from the spared senses. These mechanisms of crossmodal plasticity have been traditionally conceptualized as having a double-edged sword effect on behavior. On one side, crossmodal plasticity is conceived as adaptive for the development of enhanced behavioral skills in the remaining senses of early- deaf or blind individuals. On the other side, crossmodal plasticity raises crucial challenges for sensory restoration and is typically conceived as maladaptive since its presence may prevent optimal recovery in sensory re-afferented individuals. In the present review we stress that this dichotomic vision is oversimplified and we emphasize that the notions of the unavoidable adaptive/maladaptive effects of crossmodal reorganization for sensory compensation/restoration may actually be misleading. For this purpose we critically review the findings from the blind and deaf literatures, highlighting the complementary nature of these two fields of research. The integrated framework we propose here has the potential to impact on the way rehabilitation programs for sensory recovery are carried out, with the promising prospect of eventually improving their final outcomes.
    Full-text · Article · Aug 2014 · Neuroscience
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    • "It has been shown that basic binding ''principles,'' such as temporal coincidence, are influenced by task demands (Mé gevand et al., 2013; Stevenson and Wallace, 2013). An interesting view from sensory substitution research is that cortical functional specialization may actually be more driven by task goals than by the modality of sensory experience (Reich et al., 2012). This is based on repeated findings that task-related specialization in e.g., visual cortex is independent of the input modality (Striem-Amit et al., 2012). "
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