Understanding language and cognition after brain surgery – Tumour grade, fine‐grained assessment tools and, most of all, individualized approach

Abstract

Cognitive performance influences the quality of life and survival of people with glioma. Thus, a detailed neuropsychological and language evaluation is essential. In this work, we tested if an analysis of errors in naming can indicate semantic and/or phonological impairments in 87 awake brain surgery patients. Secondly, we explored how language and cognition change after brain tumour resection. Finally, we checked if low‐tumour grade had a protective effect on cognition. Our results indicated that naming errors can be useful to monitor semantic and phonological processing, as their number correlated with scores on tasks developed by our team for testing these domains. Secondly, we showed that – although an analysis at a whole group level indicates a decline in language functions – significantly more individual patients improve or remain stable when compared to the ones who declined. Finally, we observed that having LGG, when compared with HGG, favours patients' outcome after surgery, most probably due to brain plasticity mechanisms. We provide new evidence of the importance of applying a broader neuropsychological assessment and an analysis of naming errors in patients with glioma. Our approach may potentially ensure better detection of cognitive deficits and contribute to better postoperative outcomes. Our study also shows that an individualized approach in post‐surgical follow‐ups can reveal reassuring results showing that significantly more patients remain stable or improve and can be a promising avenue for similar reports. Finally, the study captures that plasticity mechanisms may act as protective in LGG versus HGG after surgery.

Introduction to the special issue on cognitive neurosurgery

“…Within this special issue, one of the emphases was on the discussion of postoperative impairments, adding up to the growing literature in the field (Binder et al, 2020;Miller et al, 2019;Satoer et al, 2018;Sierpowska et al, 2022). Two topics are particularly stressed, that is, the use of individualized assessments (Buunk et al, 2023;Ferrier et al, 2023;Gasa-Roqué et al, 2023;Hernández-Martínez et al, 2023;Salillas et al, 2023;van Ierschot et al, 2023); and the study of neuropsychological functions beyond language or memory, such a social cognition (Buunk et al, 2023;Coenen et al, 2023), left-right discrimination (Ruis et al, 2023), facial emotion recognition (Duits et al, 2023), apathy (Motomura et al, 2023) and aggressive behaviour, attention, impulsivity and hyperactivity (Hernández-Martínez et al, 2023). Reflection and discussion over these aspects seem relevant as patients undergoing surgery tend to have mild to moderate impairments and, therefore, surgical teams may today not only consider biological outcomes (e.g., arrest the natural progress of tumour growth, interrupt irregular brain signals due to neurodegeneration) but also avoid any major neuropsychological damage (Duffau, 2021b;Hollunder et al, 2022;Rosenow et al, 2017).…”