Naming ability changes in physiological and pathological aging

Over the last two decades, age-related anatomical and functional brain changes have been
characterized by evidence acquired primarily by means of non-invasive functional neuroimaging.
These functional changes are believed to favor positive reorganization driven by adaptations
to system changes as compensation for cognitive decline. These functional modifications
have been linked to residual brain plasticity mechanisms, suggesting that all areas of the brain
remain plastic during physiological and pathological aging. A technique that can be used to
investigate changes in physiological and pathological aging is non-invasive brain stimulation
(NIBS). The present paper reviews studies that have applied NIBS in younger and older adults
and in patients with dementia to track changes in the cerebral areas involved in a language
task (naming). The results of this research suggest that the left frontal and temporal areas
are crucial during naming. Moreover, it is suggested that in older adults and patients with
dementia, the right prefrontal cortex is also engaged during naming tasks, and naming
performance correlates with age and/or the degree of the pathological process. Potential
theories underlying the bilateral involvement of the prefrontal cortex are discussed, and the
relationship between the bilateral engagement of the prefrontal cortex and the age or degree
of pathology is explored.