Right hemisphere brain damage impairs strategy updating private schools accommodating students with learning

Right hemisphere activity may also reflect overactivation of any preserved tissue, of which there is less for people with large lesions, rather than actually remapping of function.

Furthermore, neuroimaging studies show that early engagement of the right hemisphere during the acute phase promotes recovery but that disengagement of the right hemisphere in later stages is related to ongoing successful recovery [16–19].

Increased activation in the right hemisphere during the chronic stage of aphasia is associated with naming errors [20] and overall worse performance, especially in picture-word naming and rhyme judgment [16, 21].

Additionally, right hemisphere recruitment identified in neuroimaging studies may not be a consequence of plasticity at all.

In neurologically healthy control subjects, right hemisphere activation has been shown to increase as a function of task difficulty [22, 23].

The increased activation in the preserved left hemisphere in people with aphasia has generally been associated with overall better performance [5–8].

However, the relationship between lesion size, location, and ability to use these preserved regions has not been carefully examined.

Unfortunately, the same concerns arise when examining the function of the right hemisphere as were raised for the left, specifically, confounding with lesion size and location.

The usefulness of a shift from right to left hemisphere activation during the chronic stages likely depends on the availability of remaining healthy left hemisphere tissue [5].

With regard to direct biological mechanisms underlying plasticity in language networks, relatively few specific hypotheses have been put forth.

While some investigators, including ourselves, have previously described different patterns of reorganization (e.g., compensatory “takeover” by a new area), these descriptions do not generally hypothesize a specific biological basis for these changes.

In the context of a picture naming f MRI task, we tested whether lesion size and location relate to activity in surviving left hemisphere language nodes, as well as homotopic activity in the right hemisphere during covert name retrieval and overt name production.

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