Cognitive effects of early unilateral brain injury

Date of Completion

January 1997


Psychology, Psychobiology|Psychology, Behavioral|Psychology, Cognitive




Performance on a variety of language and spatial abilities were studied in a group of 15 early unilaterally brain injured subjects and 15 age and gender matched non-brain injured controls using a series of specific cognitive tasks. The unilaterally injured subjects were further divided by side of lesion and by gender resulting in groups of: 4 Left Hemisphere Injured (LHI) Males, 6 Right Hemisphere Injured (RHI) Males and 5 Right Hemisphere Injured Females.^ Test sessions consisted of a standard Wechsler Intelligence Test, California Verbal Learning Test, Biber Figure Learning Test, Continuous Performance Test, Rey-Osterrieth Complex Figure and the Wechsler Wide Range Achievement Test-3. All test sessions were conducted by the author.^ Results indicate there are significant differences between the unilaterally injured group and the control group on Full Scale IQ scores which can be accounted for by the significantly lower Performance IQ. The unilaterally injured group specifically had difficulty with tasks that relied upon perceptual organizational and processing speed abilities. The unilaterally injured group was also impaired on measures of attention, recognition of figural designs, copying and remembering detail aspects of a complex design, and retrieval of verbal material. When groups were divided by side of injury, many of the differences noted between the Injured Group and controls persisted when comparing the RHI group with their matched controls.^ When groups were analyzed by side of lesion and gender, different cognitive patterns of impairment were noted between males and females with RHI. Male RHI subjects were impaired on various measures of verbal ability while exhibiting no significant differences, from their matched controls on spatial tasks. The RHI females appeared to exhibit a more "adult like" pattern of cognitive impairment following early right hemisphere injury, evidencing significant difficulty with various spatial tasks.^ Control females were also noted to be impaired on some spatial and attentional tasks when compared with Control males. The difficulties normal females have with these types of tasks are seemingly exacerbated by an early right hemisphere injury.^ The results suggest the need for considering different patterns of cognitive recovery following early right hemisphere injury based on gender. ^