Luria revisited: cognitive research in schizophrenia, past implications and future challenges

Contemporary psychiatry is becoming more biologically oriented in
the attempt to elicit a biological rationale of mental diseases.
Although mental disorders comprise mostly functional abnormalities,
there is a substantial overlap between neurology and psychiatry in
addressing cognitive disturbances. In schizophrenia, the presence
of cognitive impairment prior to the onset of psychosis and early
after its manifestation suggests that some neurocognitive
abnormalities precede the onset of psychosis and may represent a
trait marker. These cognitive alterations may arise from functional
disconnectivity, as no significant brain damage has been found. In
this review we aim to revise A.R. Luria's systematic approach used
in the neuropsychological evaluation of cognitive functions, which
was primarily applied in patients with neurological disorders and
in the cognitive evaluation in schizophrenia and other related
disorders. As proposed by Luria, cognitive processes, associated
with higher cortical functions, may represent functional systems
that are not localized in narrow, circumscribed areas of the brain,
but occur among groups of concertedly working brain structures,
each of which makes its own particular contribution to the
organization of the functional system. Current developments in
neuroscience provide evidence of functional connectivity in the
brain. Therefore, Luria's approach may serve as a frame of
reference for the analysis and interpretation of cognitive
functions in general and their abnormalities in schizophrenia in
particular. Having said that, modern technology, as well as
experimental evidence, may help us to understand the brain better
and lead us towards creating a new classification of cognitive
functions. In schizophrenia research, multidisciplinary approaches
must be utilized to address specific cognitive alterations. The
relationships among the components of cognitive functions derived
from the functional connectivity of the brain may provide an
insight into cognitive machinery.