Language Processing in Posterior Fossa Tumour Patients: Psycholinguistic Insights into the Word-Finding Ability

Background: Word finding - the ability to retrieve and produce appropriate words in response to prompts or visual stimuli - is impaired in some patients with a posterior fossa tumour. Yet, few studies use preoperative assessment as a baseline, and an in-depth linguistic analysis of tasks assessing word-finding ability remains limited. The current study aims to fill this knowledge gap by analysing pre- and postoperative word-finding ability and identifying its linguistic predictors. 

Method: 38 English-speaking patients (19 males and 19 females), aged between 2,5 and 17,6 years and diagnosed with posterior fossa tumours were assessed before and after surgery. Performance was assessed using a picture-naming task, Wordrace, measuring both accuracy and reaction times. These measures were interpreted in terms of their correlation with linguistic levels (i.e., lexical, semantic, phonological). 

Results: Patients exhibited a significant slowing in word-finding speed following surgery, while accuracy remained stable across assessment points. Despite this decline in speed, we did not find evidence for a change in the influence of psycholinguistic factors on word-finding ability in our sample. Lexical-semantic variables predicted word-finding speed, whereas accuracy was influenced only by lexical variables. 

Conclusion: The findings suggest that although general performance declined postoperatively, we did not find evidence in our sample of disruption to the underlying linguistic processes engaged during word-finding. However, the absence of control group limits interpretation, and future studies comparing patients with healthy controls may reveal more subtle differences. The study emphasises the importance of longitudinal assessment in patients with posterior fossa tumours and future studies should incorporate additional timepoints to examine the potential effects of radiotherapy and chemotherapy on word-finding over time.