BRAIN MEANDERING PATHWAY
Maturity, the thinking goes,
comes with age. However, this
the journey from childhood to
adulthood is uneven: some
mental attributes surface faster than others, some are
more pronounced in girls,
and poverty and trauma have
an outsized influence on cognitive development, says one
of the largest studies of its
kind, spanning nearly 9,000
children and young adults
from India.
The CVeda
The study is part of a long-term project called the ‘Consortium on Vulnerability to
Externalizing Disorders and
Addictions’ (CVeda). It aims
to follow up on those tested over
decades, and evaluate the effect of biological and environmental risk on cognitive
development.
Brain development progresses from childhood to early adulthood with wideranging connections among
neurons in multiple parts of
the brain. This connectivity significantly influences abilities such as temporarily holding chunks of information,
called ‘working memory (for
instance, memorizing a phone
the number before writing it
down) and ‘set shifting’ (iterating multiple ways to solve a
puzzle). These skills are classified as executive functions.
Another category of functions, called social cognition
help mediate relationships.
A consortium of psychiatrists, neurologists, and psychologists from India and the U.K.,
investigating the Role of Environment and Genetics on
brain development analyzed
four kinds of executive functions: verbal working memory, visuospatial working memory, response inhibition (the
ability to stop one task and begin another), setshifting and
two kinds of social cognition:
faux pas recognition (inferring
social cues) and emotion recognition (inferring another’s
state of mind).
They report, in the April
2023 edition of the peerreviewed Asian Journal of Psychiatry, that ‘working memory’ develops first, followed by
inhibitory control and finally
cognitive flexibility. However,
certain abilities such as visual
and verbal reasoning stabilized by late adolescence and
didn’t rise as people aged, whereas cognitive ability and
emotional cognition continued to develop even after
adolescence, Eesha Sharma,
the lead author of the study, Senior Resident Department of Psychiatry National Institute of Mental Health & Neurosciences Bangalore - 560029.
The studies, spanning a
range of socioeconomic
groups, ages, urbanization
and gender also found that
children who manifested certain traits to a high degree outperformed their peers in that
skill even as they aged, while other traits didn’t constitute a
permanent advantage.
“Response inhibition has a
ceiling. If you are low performing early on, you will
catch up as you grow older. It
was the other way, however,
in verbal working memory. Those who did well in early
childhood continued to significantly outperform their
peers,” said Dr. Sharma, an assistant professor at the National Institute of Mental Health
and Neurosciences, Bengaluru. “However, what all this
means in the real world is a
question that we are still analyzing.”
Complex abilities
The more ‘complex abilities’ —
response inhibition, cognitive
flexibility, and emotion recognition — are “maximally impacted” by environments
such as poverty or childhood
adversity. “No matter which ability
you are looking at, children in
wealthier households do better,” she said.
CVeda expects to map the
brains of those participating
in the study and evaluate and
compare neurologically
development. “If we can generate brain development charts across ages, just like how there are
charts for physical growth, it
could be a valuable tool in
schools and mental health assessments,” Dr. Sharma said.
