Childhood brain tumours affect working memory of survivors

New York: Survivors of childhood brain tumours have lower working memory performance in adulthood compared to healthy adults, new research has found.

The researchers studied the working memory of adult survivors of childhood posterior fossa brain tumours versus a healthy control sample using functional magnetic resonance imaging (fMRI) and neuropsychological measures. 

Each group consisted of 17 participants.

During fMRI, the participants completed a measure called the n-back task. 

They were asked to monitor a series of letters. Accurately recalling a letter two or three letters back represented higher working memory capabilities. Participants also completed other standardised clinical measures.

"Our goal was to identify the neural mechanisms underlying working memory difficulty in adult survivors of childhood brain tumours," said Tricia King, associate professor of psychology and neuroscience at Georgia State University in the US.

"The results suggest that adult survivors of pediatric posterior fossa brain tumours recruited additional resources to control cognitive ability in the prefrontal lobe during increased demands for working memory. This increased prefrontal activation is associated with lower working memory performance," King noted.

Adult survivors of childhood brain tumours are at risk for neurocognitive deficits, such as working memory impairment, that contribute to poor long-term outcomes, the study concluded.

Working memory deficits are also common in other neurological conditions, such as schizophrenia, multiple sclerosis and traumatic brain injury, because working memory is an essential component for higher-order cognitive processes in humans.

The study was published in the Journal of the International Neuropsychological Society.