Photo Credit: freepik
The following is a summary of “Association of Normative and Non-Normative Brain Networks With Cognitive Function in Patients With Temporal Lobe Epilepsy,” published in the September 2024 issue of Neurology by Zhang et al.
Patients with Temporal lobe epilepsy (TLE) can still have normal cognitive function despite their temporal lobe damage.
Researchers conducted a retrospective study identifying patients with TLE with intact or impaired neurocognitive profiles and investigating the presence of both standard and unique intrinsic connectivity networks (ICNs) to understand the transition from impaired to intact neurocognitive status.
They involved patients with TLE and matched HCs from the Thomas Jefferson Comprehensive Epilepsy Center. Functional MRI data were analyzed through independent component analysis to generate individualized ICNs. The study assessed how closely these individualized ICNs matched canonical ICNs (e.g., 17 resting-state networks by Yeo et al.) and classified each participant’s ICNs as normative or non-normative based on this match.
The results showed 100 patients with TLE (mean age 42.0 [SD: 13.7] years, 47 women) and 92 HCs. Individualized networks matched less well with canonical networks in cognitively impaired patients (n = 24) compared to cognitively intact patients (n = 63), with a mean difference of −0.165 (−0.317, −0.013), P=0.028. In impaired patients, there were significant abnormalities in both normative and non-normative networks, while intact patients showed abnormalities only in non-normative networks. Unlike non-normative networks, normative networks had a strong positive correlation with neuropsychological measures.
They concluded that data showed significant cognitive deficits were linked to canonical and highly individual ICNs, indicating that the transition from intact to impaired cognitive status was not solely due to disruptions in normative brain networks.