Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Apr;31(4):e70298.
doi: 10.1111/cns.70298.

Dynamic and Static Functional Gradient in Temporal Lobe Epilepsy With Hippocampal Sclerosis Versus Healthy Controls

Kangrun Wang  1   2 , JiaYao Li  2   3 , Fangfang Xie  4 , Chaorong Liu  2 , Langzi Tan  2   5 , Jialinzi He  2 , Xianghe Liu  2 , Ge Wang  2 , Min Zhang  2 , Haiyun Tang  4 , Danlei Wei  2 , Jingwan Feng  2 , Sha Huang  2 , Jinxin Peng  2 , Zhuanyi Yang  6 , Xiaoyan Long  2 , Bo Xiao  2   7 , Juan Li  2 , Lili Long  2   3
Affiliations

Dynamic and Static Functional Gradient in Temporal Lobe Epilepsy With Hippocampal Sclerosis Versus Healthy Controls

Kangrun Wang et al. CNS Neurosci Ther. 2025 Apr.

Abstract

Aims: The gradient captures the continuous transitions in connectivity, representing an intrinsic hierarchical architecture of the brain. Previous works hinted at the dynamics of the gradient but did not verify them. Cognitive impairment is a common comorbidity of temporal lobe epilepsy (TLE). Gradient techniques provide a framework that could promote the understanding of the neural correlations of cognitive decline.

Methods: Thirty patients with TLE and hippocampal sclerosis and 29 matched healthy controls (HC) were investigated with verbal fluency task-based functional MRI and gradient techniques. The correlation between task-based activation/deactivation and healthy gradients, task-based gradients, and dynamic features calculated with sliding window approaches was compared between HC and TLE.

Results: The allegiance in the real data of HC and TLE was more widespread compared to static null models. TLE has lower dynamic recruitment of gradient, atypical activation-gradient correlation, and contracted principal gradient. Correlation analysis proved that the reconfiguration of principal gradient did not drive the reorganization of activation. The atypical activation pattern and impaired recruitment were correlated with cognition scales in TLE.

Discussion: The principal gradient is dynamic. TLE disrupted activation/deactivation patterns, the principal gradient, and the dynamics of the gradient, which were correlated with cognitive decline.

Keywords: dynamic; fMRI; gradient; temporal lobe epilepsy.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflicts of interest.

Figures

FIGURE 1
FIGURE 1
Validation of gradient techniques in task‐based data. (A) The task‐based gradient in healthy controls; (B) correlation between resting‐state gradient and task‐based gradient; (C) correlation between beta signals and the principal gradients.
FIGURE 2
FIGURE 2
Dynamic gradient. (A) the distribution of allegiance in real data and the static null model; (B) the flexibility of networks; (C) the recruitment of networks. CCN, cognitive control network; DAN, dorsal attention network; DMN, default mode network; HC, healthy controls; LIM, Limbic system; SAN, salience network; SMC, somatomotor cortex; TLE, temporal lobe epilepsy; VIS, visual cortex; *, p < 0.05.
FIGURE 3
FIGURE 3
Static gradient. (A) the loading scores of networks; (B) the distribution of the gradients in HC and TLE; (C) the correlation between beta signals of TLE and the principal gradient of HC or TLE. CCN, cognitive control network; DAN, dorsal attention network; DMN, default mode network; HC, healthy controls; LIM, Limbic system; SAN, salience network; SMC, somatomotor cortex; TLE, temporal lobe epilepsy; VIS, visual cortex; *, p < 0.05.
See this image and copyright information in PMC

References

    1. Allone C., Lo Buono V., Corallo F., et al., “Neuroimaging and Cognitive Functions in Temporal Lobe Epilepsy: A Review of the Literature,” Journal of the Neurological Sciences 381 (2017): 7–15, 10.1016/j.jns.2017.08.007. - DOI - PubMed
    1. Wang K., Xie F., Liu C., et al., “Abnormal Functional Connectivity Profiles Predict Drug Responsiveness in Patients With Temporal Lobe Epilepsy,” Epilepsia 63, no. 2 (2022): 463–473, 10.1111/epi.17142. - DOI - PubMed
    1. Trimmel K., Caciagli L., Xiao F., et al., “Impaired Naming Performance in Temporal Lobe Epilepsy: Language fMRI Responses Are Modulated by Disease Characteristics,” Journal of Neurology 268, no. 1 (2021): 147–160, 10.1007/s00415-020-10116-x. - DOI - PMC - PubMed
    1. Caciagli L., Paquola C., He X., et al., “Disorganization of Language and Working Memory Systems in Frontal Versus Temporal Lobe Epilepsy,” Brain 146, no. 3 (2022): 935–953, 10.1093/brain/awac150. - DOI - PMC - PubMed
    1. Trimmel K., van Graan A. L., Caciagli L., et al., “Left Temporal Lobe Language Network Connectivity in Temporal Lobe Epilepsy,” Brain 141, no. 8 (2018): 2406–2418, 10.1093/brain/awy164. - DOI - PubMed