| Widespread memory problems have been reported following closed head injury (CHI). However, research has revealed multiple dissociations in memory functioning, such as conscious vs. unconscious memory, which are termed explicit and implicit memory, respectively. Thus, it may be that not all aspects of memory are equally impaired among individuals who have sustained a CHI. The current study investigated implicit and explicit memory functioning in 24 children with moderate CHI (M age = 11.4 years; range = 7.5--14.2 years) and 24 age- and gender-matched controls. Study conditions involved reading words and naming pictures. Implicit memory was subsequently examined using both lexical (word-stem completion) and pictorial (picture-fragment identification) tasks, and explicit memory was assessed using a yes/no recognition test. The CHI participants exhibited preserved implicit memory and showed a normal pattern of transfer-appropriate processing for both words and pictures despite impaired explicit memory. Specifically, priming on the word-stem completion task was greatest following word study, and priming on the picture-fragment identification task was greatest following picture study. Explicit memory testing revealed that children with CHI failed to show the standard picture-superiority effect demonstrated by the control participants. Clinical neuropsychological abilities (e.g., visual perception and executive functioning) were also examined in relation to the experimental measures. Most of the clinical measures were related to explicit memory, but only one executive measure was related to implicit memory performance. These results are consistent with those reported in the adult CHI literature and have implications for the understanding and rehabilitation of memory impairments in children with CHI. Specifically, the identification of spared implicit processing operations may serve as a basis for constructing novel memory-based interventions and rehabilitation for children who sustain CHIs. |
