Ann Rehabil Med.  2018 Aug;42(4):617-620. 10.5535/arm.2018.42.4.617.

Which Neural Tract Plays a Major Role in Memory Impairment After Multiple Cerebral Infarcts? A Case Report

• Park DK
• Byun KH
• Yang D

• KMID: 2420055
• DOI: http://doi.org/10.5535/arm.2018.42.4.617

Abstract

Injury to the thalamocortical tract (one in the Papez circuit) that leads to memory impairment following brain injury is very rare. In this study, we present a case of partial injury to the thalamocortical tract that causes memory impairment after concurrent thalamic and hippocampal infarct. A 20-year-old male complained of memory impairment 1 month after partial injury to the thalamocortical tract. Using a probabilistic diffusing tensor tractography, it was found that the right thalamocortical tract was thinner than the left thalamocortical tract. However, all other neural tracts including the fornix, cingulum, and mammillothalamic tract were intact on both hemispheres. Therefore, the memory impairment in this patient was considered as being due to thalamic infarct based on the observation that the fornix from hippocampal infarct was intact. This case suggests that the assessment of lesions in the neural tracts of the Papez circuit might be useful for understanding the mechanism of memory impairment following cerebral infarction.

Keyword

Cerebral infarction; Limbic system; Memory deficit

MeSH Terms

Brain Injuries
Cerebral Infarction
Humans
Limbic System
Male
Memory Disorders
Memory*
Young Adult

Figure

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  Fig. 1. (A) Diffusion brain magnetic resonance imaging showed cerebral infarction in the anterior thalamus, hippocampus, and the partially fusiform area on the right hemisphere. (B) The right thalamocortical tract (green color) between the anterior thalamic nuclei and the cingulate gyrus is thinner compared to the left thalamocortical tract (yellow arrow). Other tracts such as the mammillothalamic tract (pink), fornix (blue), and cingulum (red) are well constructed without abnormality. R, right; A, anterior.

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