Jinping Liu1, Zhao Zhang1, Xia Zhou1, Xiaomin Pang1, Xiulin Liang1, Huanjian Huang1, Lu Yu1, Jinou Zheng2. 1. Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China. 2. Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China. Electronic address: jinouzheng@163.com.
Abstract
OBJECTIVE: Focal impaired awareness seizures are common in temporal lobe epilepsy (TLE). The cognitive impairment associated with this type of seizure is unclear. Alertness is a fundamental aspect of cognition. The locus coeruleus (LC) is closely related to alertness. We aimed to assess the impairment in alertness and LC-related alertness network in patients with focal impaired awareness seizures. METHODS: Patients with unilateral TLE were grouped into the only focal impaired awareness seizure group (focal group, n = 19) and the focal impaired awareness seizure with focal to bilateral tonic-clonic seizure (FBTCS) group (FBTCS group, n = 19) and compared with matched healthy controls (HC, n = 19). Alertness was assessed with the attention network test. Functional magnetic resonance imaging (fMRI) was used to construct an alertness-related LC-based functional connectivity (FC) network. RESULTS: The focal group exhibited impaired tonic and phasic alertness and exhibited a decreased trend of LC-based FC to the left superior frontal gyrus (SFG). The FBTCS group exhibited impaired tonic alertness, phasic alertness, and alertness efficiency. No significant difference or trend in LC-based FC was found in the FBTCS group. SIGNIFICANCE: This study reveals disrupted alertness and alertness-related LC-based FC in patients with focal impaired awareness seizures. Our results further demonstrate that the patterns of impaired alertness and of changed LC-based FC were not significantly different between focal impaired awareness seizures and FBTCS.
OBJECTIVE:Focal impaired awareness seizures are common in temporal lobe epilepsy (TLE). The cognitive impairment associated with this type of seizure is unclear. Alertness is a fundamental aspect of cognition. The locus coeruleus (LC) is closely related to alertness. We aimed to assess the impairment in alertness and LC-related alertness network in patients with focal impaired awareness seizures. METHODS:Patients with unilateral TLE were grouped into the only focal impaired awareness seizure group (focal group, n = 19) and the focal impaired awareness seizure with focal to bilateral tonic-clonic seizure (FBTCS) group (FBTCS group, n = 19) and compared with matched healthy controls (HC, n = 19). Alertness was assessed with the attention network test. Functional magnetic resonance imaging (fMRI) was used to construct an alertness-related LC-based functional connectivity (FC) network. RESULTS: The focal group exhibited impaired tonic and phasic alertness and exhibited a decreased trend of LC-based FC to the left superior frontal gyrus (SFG). The FBTCS group exhibited impaired tonic alertness, phasic alertness, and alertness efficiency. No significant difference or trend in LC-based FC was found in the FBTCS group. SIGNIFICANCE: This study reveals disrupted alertness and alertness-related LC-based FC in patients with focal impaired awareness seizures. Our results further demonstrate that the patterns of impaired alertness and of changed LC-based FC were not significantly different between focal impaired awareness seizures and FBTCS.