Long-Term Consequences of Severe Closed Head Injury on Episodic Memory

Abstract

This is the first systematic investigation of the very long-term effects of severe closed head injury (CHI) on objective measures of memory, and the first to employ both a normal control group and an 'other injury' control group consisting of spinal cord injury (SCI) patients. The CHI group displayed significantly poorer performance on every memory measure, and the effect sizes were large. This impairment in episodic memory is neither due to pre-injury nor post-injury differences between CHI and normal control subjects because the same differences were found when the CHI group was compared to a group of SCI patients. The findings demonstrate severe impairment in learning and retention many years after sustaining a severe CHI, which is likely in part due to the bilateral hippocampal damage shown in neuropathological studies. This life-long memory impairment needs to be addressed by community service programs.

Diffusion Tensor Imaging of the Perforant Pathway Zone and Its Relation to Memory Function in Patients with Severe Traumatic Brain Injury

“…Most studies with patients who sustained moderate to severe TBI have found impaired memory (Blachsteni et al, 1993;Millis and Ricker, 1994;Vakil, 2005;Vanderploeg et al, 2001). In addition, recovery of learning and memory functions has been found to be slower compared to other TBI cognitive abilities (Lezak, 1979), with deficient learning and memory persisting after moderate to severe TBI (Zec et al, 2001). TBI usually affects temporal lobes bilaterally, and thus memory impairment is nonspecific (Mapou, 1992).…”

Atypical within-session motor procedural learning after traumatic brain injury but well-preserved between-session procedural memory consolidation

“…Multiple memory modalities can be affected. While explicit memory impairment is well-documented (Zec et al, 2001), less is known about procedural ("how to" knowledge) learning and memory deficits in patients with TBI, with disagreement about whether these occur and to what extent (Vakil, 2005). Even less is known about the time-course of multi-session training in TBI.…”

Neuropsychological Assessment of Moderate to Severe Traumatic Brain Injury

“…Because the investigators controlled for acquisition differences and for ceiling effects on recall and recognition measures, they attributed their findings to a consolidation deficit. A more rapid rate of forgetting has also been reported in other studies (Stuss et al, 1985, Zec et al, 2001, regardless of whether they controlled for acquisition differences between groups. Nevertheless, similar rates of forgetting by patient and control groups were found by DeLuca et al (2000) when groups were equated for initial levels of learning.…”

“…In one study conducted an average of 3.25 years postinjury, patients with PTA greater than 3 weeks were impaired on the Logical Memory subtest of the WMS and on the delayed recall trial of the Rey Complex Figure Test compared to orthopedic controls (Bennett-Levy, 1984). Another study reported that a group that had sustained a severe TBI an average of 10 years earlier performed more poorly than a spinal cord injury group on several verbal and visual memory tests (Zec et al, 2001). Measures included the Buschke Selective Reminding Test, RAVLT, and WMS-R.…”

“…A tendency to retrieve items that were not presented or to answer "yes" to items not previously encountered has been observed on verbal (Crosson et al, 1988;Zec et al, 2001) and visual (e.g., Levin & Goldstein, 1986;Shum et al, 2000) recall and recognition tasks.…”