Item and order recognition memory in subjects with hypoxic brain injury.

Subjects with hypoxic brain injury resulting in significant cell loss in the hippocampus but not the parahippocampal gyrus or temporal lobes and normal control subjects were tested for memory impairments. The Denman Memory Scale was given to all subjects as a baseline memory assessment. All subjects were then tested for item and order recognition memory for lists of six words, pictures, abstract pictures, spatial locations, and motor responses. Results indicated that hypoxic subjects are impaired compared to control subjects on the Denman memory scale for verbal, non-verbal, and full-scale memory quotients. In addition, results indicated that compared to control subjects, hypoxic subjects displayed item and order recognition deficits for words, pictures, abstract pictures, and spatial locations. A recency effect for item recognition of abstract pictures, spatial locations, and hand positions was found. For motor response order recognition, both primacy and recency effects were found, with deficits in performance for the middle items of the list. It appears that subjects with hypoxic brain injury in the face of severe memory deficits for words, pictures, abstract pictures, and spatial locations display residual capacity for remembering the last items for spatial locations, abstract designs, and hand positions. Hypoxic subjects also display residual capacity for remembering motor responses using episodic or data-based memory.