title: Trail making test B and brain perfusion imaging in mild cognitive impairment and mild Alzheimer's disease.
abstract: The trail making test (TMT) has long been used to investigate deficits in cognitive processing speed and executive function in humans. However, there are few studies that elucidate the neural substrates of the TMT. The aim of the present study was to identify the brain regional perfusion patterns associated with performance on TMT part B (TMT-B) in patients with amnestic mild cognitive impairment (aMCI) or mild Alzheimer's disease (AD). Twenty-one patients with good TMT-B scores and 21 age- and sex-matched patients with poor TMT-B scores were selected. All 42 subjects underwent brain single photon emission computed tomography (SPECT), and the SPECT images were analyzed by statistical parametric mapping. No significant differences between good- and poor-scoring groups were found with respect to years of education, Addenbrooke's Cognitive Examination scores, and scores on TMT-A. Compared to patients with good scores on TMT-B, patients with poor scores showed significant hypoperfusion in the bilateral anterior cingulate extending to the posterior region on the right side, bilateral caudate nucleus and putamen, and bilateral thalamus. Analysis of 63 AD or aMCI subjects revealed significant correlation a between regional cerebral blood flow in the right cingulate cortex and TMT-B scores. Our results suggest that functional activity of the anterior cingulate, striatum and thalamus is closely related to performance time on TMT-B. The performance time on the TMT-B score might be a promising index of dysfunction of the anterior cingulate, striatum, and thalamus among patients with aMCI or mild AD.
authors.affiliation: Department of Neuropsychiatry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan. terada@cc.okayama-u.ac.jp
authors.forename: Seishi
authors.initials: S
authors.lastname: Terada
authors.forename: Shuhei
authors.initials: S
authors.lastname: Sato
authors.forename: Shigeto
authors.initials: S
authors.lastname: Nagao
authors.forename: Chikako
authors.initials: C
authors.lastname: Ikeda
authors.forename: Aki
authors.initials: A
authors.lastname: Shindo
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hayashi
authors.forename: Etsuko
authors.initials: E
authors.lastname: Oshima
authors.forename: Osamu
authors.initials: O
authors.lastname: Yokota
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Uchitomi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000150:complications* / Q000523:psychology; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology*; D002560:Cerebrovascular Circulation; D003072:Cognition Disorders / Q000209:etiology* / Q000473:pathology*; D003545:Cysteine / Q000031:analogs & derivatives; D005260:Female; D006801:Humans; D008297:Male; D015609:Organotechnetium Compounds; D055420:Perfusion Imaging; D011569:Psychiatric Status Rating Scales; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon; D014145:Trail Making Test
chemical_list: D015609:Organotechnetium Compounds; C059659:technetium Tc 99m bicisate; D003545:Cysteine
keywords: Alzheimer's disease (AD); Amnestic mild cognitive impairment (aMCI); Cerebral blood flow (CBF); Trail Making Test (TMT)