Hypothyroidism is associated with significant neurocognitive deficits that develop across the life span. This article discusses the patterns of cognitive deficits associated with congenital and adult-onset hypothyroidism. A review of the extant literature shows that the successful treatment of clinically evident thyroid gland hypofunction, resulting in a return to euthyroidism in both infants and adults, may be associated with only partial and typically inconsistent patterns of recovery of overall neurocognitive function. In addition to demonstrating different patterns of cognitive impairments, patients with congenital and acquired adult-onset hypothyroidism have variable responses to thyroid replacement therapy, which increases the risk of higher neurocognitive morbidity associated with congenital hypothyroidism. An evaluation of the commonly held view that hypothyroid dementia is an imminently reversible condition is only partially supported by the medical literature, which is fraught with methodological and conceptual shortcomings. I offer some recommendations for addressing the cognitive and behavioral management concerns of individuals with clinical hypothyroidism.

Abstract. Pathologic studies of central nervous system damage in human falciparum malaria indicate primary localization in the cerebral white matter. We report a sensory-perceptual investigation of 20 Ghanaian children with a recent history of cerebral malaria who were age-, gender-, and education-matched with 20 healthy control subjects. Somatosensory examinations failed to show any evidence of hemianesthesia, pseudohemianesthesia, or extinction to double simultaneous tactile stimulation. While unilateral upper limb testing revealed intact unimanual tactile roughness discrimination, bimanual tactile discrimination, however, was significantly impaired in the cerebral malaria group. A strong negative correlation (r ϭ Ϫ0.72) between coma duration and the bimanual tactile roughness discrimination test was also found. An inefficiency in the integrity of callosal fibers appear to account for our findings, although alternative subcortical mechanisms known to be involved in information transfer across the cerebral hemispheres may be compromised as well.An estimated 40% of the world's population is exposed to malaria.1 In Africa, children are at particular risk of developing the imminently lethal complications of Plasmodium falciparum infection, with 90% of all malaria deaths being pediatric cases. 2 We are far from understanding why some children in malaria endemic areas who develop symptomatic manifestations of falciparum malaria progress to the more severe cerebral malaria while others do not.3 There is also scant, but increasing evidence of neurologic deficits in both uncomplicated falciparum malaria 4-6 and cerebral malaria, 7-9 with an estimated 5-10% of African children developing significant and neurologic sequelae following cerebral malaria. These include sensory (i.e., hearing deficits, cortical blindness, and other visual field defects) and motor (i.e., ataxic and paretic) disorders.Recent advances in neuroradiologic imaging technologies have improved the diagnostic accuracy of detecting neuropathological changes in cerebral malaria 10,11 over earlier, lower resolution methods.12 Unfortunately, however, neuropsychologic aspects of cerebral malaria have received very little clinical or research attention. Cerebral white matter lesions have been strongly associated with cerebral malaria, 13,14 with axonal demyelination 15 and local cerebral hypoxic effects 14 thought to be among its pathologic sequelae. The human corpus callosum is the largest neocortical fiber tract in the brain, and along with other forebrain commissures, facilitates efficient communication between the cerebral hemispheres. If indeed cerebral malaria shows a predilection for cerebral white matter, one can hypothesize interhemispheric transfer inefficiencies on neuropsychologic evaluation. To investigate this possibility, the efficiency in transmission of tactile somesthetic information across the cerebral hemispheres was studied in a sample of Ghanaian children. MATERIALS AND METHODSStudy area and study population. Accra, the capital of Ghana...

This study investigated the long-term emotional and cognitive effects of malaria infection in a sample of community resident nonmigratory Ghanaian adults, comparing 142 individuals with a documented history of clinical falciparum malaria and 30 controls without a lifetime medical diagnosis of malaria. Results were based on self-report inventory and interview-based approaches to assessment of emotional status as well as individual administration of the Mini-Mental State Examination. Our findings indicated the presence of an enduring, albeit subclinical, mixed anxiety-depression syndrome after medical recovery from falciparum malaria. There were, however, no significant neurocognitive deficits associated with malaria status on the objective screening instrument, nor were there reports of subjective attention, concentration, memory, or other cognitive complaints by self-report. Malaria may be a risk factor for psychiatric morbidity. We therefore recommend a search for effective malaria prevention and intervention strategies to avert the more serious clinical manifestations of mental disorder likely to evolve in this imminently lethal infectious disease.

The Color Trails Test (CTT) has been described as a culture-fair test of visual attention, graphomotor sequencing, and effortful executive processing abilities relative to the Trail Making Test (TMT). In this study, the equivalence of the TMT and the CTT among a group of 64 bilingual Turkish university students was examined. No difference in performance on the CTT-1 and TMT Part A was found, suggesting functionally equivalent performance across both tasks. In contrast, the statistically significant differences in performance on CTT-2 and TMT Part B, as well as the interference indices for both tests, were interpreted as providing evidence for task nonequivalence of the CTT-2 and TMT Part B. Results have implications for both psychometric test development and clinical cultural neuropsychology.

The Color Trails Test (CTT) has been described as a culture-fair test of visual attention, graphomotor sequencing, and effortful executive processing abilities relative to the Trail Making Test (TMT). In this study, the equivalence of the TMT and the CTT among a group of 64 bilingual Turkish university students was examined. No difference in performance on the CTT-1 and TMT Part A was found, suggesting functionally equivalent performance across both tasks. In contrast, the statistically significant differences in performance on CTT-2 and TMT Part B, as well as the interference indices for both tests, were interpreted as providing evidence for task nonequivalence of the CTT-2 and TMT Part B. Results have implications for both psychometric test development and clinical cultural neuropsychology.