Functional MRI of working memory in paediatric head injury

Adolescent Brain and Cognitive Developments: Implications for Clinical Assessment in Traumatic Brain Injury

Adolescence is a time of significant physical, social, and emotional developments, accompanied by changes in cognitive and language skills. Underlying these are significant developments in brain structures and functions including changes in cortical and subcortical gray matter and white matter tracts. Among the brain regions that develop during adolescence are areas that are commonly damaged as a result of a traumatic brain injury (TBI). This paper summarizes major brain changes during adolescence and evidence linking maturation of these cognitive and language functions to brain development, placing consideration of both areas of development in the context of rehabilitation for adolescents with TBI.

Variability in Stroop task performance and functional activation among a small brain-injured group

This study evaluated the effects of moderate to severe brain injury on cognitive task performance and cortical activation. Five participants completed a Stroop task while undergoing functional magnetic resonance imaging (fMRI) at two time points post- injury. Results revealed activation within regions typically activated during a Stroop task (the region of interest: ROI), though variability among participants was evident. Regions outside of the ROI were activated among all participants, to a greater degree than was present within the ROIs. This finding may indicate that recruitment of outside regions was necessary for successful task completion at both time points, and may suggest functional plasticity in cognitive task completion.

The use of functional MRI in traumatic brain injury diagnosis and treatment

Recent advances in MRI have provided the opportunity to map changes in hemodynamics that correspond to cognitive and sensory operations. These advances in noninvasive, low-risk, imaging environments have extended the traditional role of medical imaging into new domains that include investigations into the interplay between brain anatomy, physiology, and function. This interplay is mandatory for examination of the complex effects of diffuse damage caused by traumatic brain injury. Functional MRI (fMRI) provides relatively high-resolution indirect assessment of neuronal activity. Three main factors interact to affect the quality of fMRI data that is acquired: (1) MRI hardware, (2) the paradigm (or experimental) design, and (3) subject cooperation. This article focuses on paradigm design and subject cooperation.