Memory performance is related to language dominance as determined by the intracarotid amobarbital procedure.

OBJECTIVE: The goal of this study was to explore the relationship between language and memory lateralization in patients with epilepsy undergoing the intracarotid amobarbital procedure. METHODS: In 386 patients, language lateralization and memory lateralization as determined by laterality index (LI) were correlated with each other. RESULTS: Language lateralization and memory lateralization were positively correlated (r=0.34, P<0.01). Correlations differed depending on the presence and type of lesion (chi(2)=7.98, P<0.05). LIs correlated significantly higher (z=2.82, P<0.05) in patients with cortical dysplasia (n=41, r=0.61, P<0.01) compared with the group without lesions (n=90, r=0.16, P>0.05), with patients with hippocampal sclerosis falling between these two groups. Both memory (P<0.01) and language (P<0.01) LIs were higher in right- compared with left-sided lesions. CONCLUSION: Correlation of language and memory is more pronounced in patients with structural lesions as compared with patients without lesions on MRI.

Visual naming performance after ATL resection: impact of atypical language dominance.

PURPOSE: To characterize the interaction between language dominance and lateralization of the epileptic focus for pre- and postoperative Boston Naming Test (BNT) performance in patients undergoing anterior temporal lobectomy (ATL). METHODS: Analysis of pre- and postoperative BNT scores depending on lateralization of language as measured by the intracarotid amobarbital procedure (IAP) versus lateralization of the temporal lobe epileptic focus. RESULTS: Changes between pre- and postoperative BNT performance depended on epilepsy lateralization (effect size=0.189) with significant decrease in patients undergoing left ATL. Subgroup analysis in these showed that postoperative decline in BNT scores was significant in patients with atypical (n=14; p<0.05), but did not reach statistical significance in patients with left language dominance (n=36; p=0.09). Chi-square test revealed a trend of higher proportions of patients experiencing significant postsurgical deterioration in naming performance in atypical (57.1%) as compared to left language dominance (30.6%; p=0.082). Surgical failure was also associated with greater decline of BNT scores and was more common in atypical than in left language dominant patients (chi(2) (1, n=98)=4.62, p=0.032). Age of onset, duration of epilepsy, and seizure frequency had no impact on changes in BNT performance. CONCLUSION: Atypical language dominance is a predictor of change in visual naming performance after left ATL and may also impact postsurgical seizure control. This should be considered when counseling surgical candidates.

ApoE-epsilon4 is associated with reduced memory in long-standing intractable temporal lobe epilepsy.

OBJECTIVE: To investigate the relationship between the apolipoprotein (ApoE) epsilon4 allele and memory performance (verbal and nonverbal) in patients with medically intractable temporal lobe epilepsy (TLE) who underwent temporal lobectomy. METHODS: Presurgical and postsurgical memory performance was examined in 87 adult patients with TLE (epsilon4 = 22; non-epsilon4 = 65) to determine whether the expression of ApoE-epsilon4 may be associated with memory performance in this population and to examine how this relationship may be affected by duration of epilepsy. RESULTS: There was a significant interaction between ApoE-epsilon4 status and duration of epilepsy such that epsilon4 carriers with a long duration of epilepsy demonstrated the poorest memory performance on both verbal and nonverbal measures. This relationship was observed both before and after temporal lobectomy, with little change in test performance over time. CONCLUSIONS: The ApoE-epsilon4 allele interacts with longstanding seizures to affect memory performance, both verbal and nonverbal, in patients with medically intractable temporal lobe epilepsy.

Aging of attention: does the ability to divide decline?

Previous research has yielded conflicting results regarding the relationship between adult age and the ability to divide attention between two concurrent tasks. At least some of the inconsistency is probably attributable to methodological variations, such as the manner in which divided-attention ability has been assessed, how single-task performance has been considered, and the degree of control over relative emphasis placed on each task. Two experiments employing procedures sensitive to these concerns were conducted in which a speeded decision task was performed during the retention interval of a letter-memory task. The results of both experiments indicated that there were relatively few age-related influences on dual-task performance vis-à-vis those on single-task performance.

A normative study of Nelson's (1976) modified version of the Wisconsin Card Sorting Test in healthy older adults.

A modified version of the Wisconsin Card Sorting Test (mWCST) proposed by Nelson (1976) was administered to 229 healthy community-dwelling older adults, composed of 97 men and 132 women, ages 45 to 91. Investigating the impact of demographic factors such as age, education, and gender on mWCST performance, results indicated that mWCST performance was significantly affected by both age and education. Unlike the standard WCST, however, gender did not significantly influence mWCST performance. Because demographic factors appear to exert a significant influence on mWCST performance of normal older adults, demographically-corrected norms were calculated according to the procedure described by Heaton, Grant, and Matthews (1991). In addition, longitudinal analysis of mWCST performance revealed that significantly fewer nonperseverative errors were committed at retest approximately one year later. Number of categories completed and perseverative errors did not appear to demonstrate significant practice effects in this sample. Accounting for demographic influences and the inspection of practice effects on serial administration of the mWCST may improve upon its sensitivity and specificity for use in the clinical assessment of executive function in older adults.