Biology subjects

Platt, A. L. M.

Publications and source records attributed to Platt, A. L. M..

2 recordsLinked to original sources

bioRxiv2025

Individual-level contextual alignment and aperiodic slope reveal improved comprehension of unexpected language

In everyday language use, individuals are required to comprehend complex, continuous and often unexpected linguistic inputs to effectively communicate with others. Evidence from other domains of processing such as memory and learning suggest that individuals these unexpected inputs can often be remembered or learnt just as well as predictable inputs in follow up testing. However, language comprehension research often focuses on how individuals process these stimuli rather than how the information which is gathered can be used at a later time. It is proposed that, in line with memory and learning, individuals can utilise unexpected language inputs to support a deeper understanding of the information which is being communicated. Further, this will be related to the interaction between an individuals alignment to local context and inter-individual differences in information processing, such as aperiodic slope. The present study uses an alignment metric which measures the relationship between individual level N400 amplitudes (a neurophysiological metric of predictability) and surprisal (a text-collection-based metric of predictability), where higher alignment suggests the individual has a stronger preexisting schema. A steeper aperiodic slope has been suggested to reflect greater adaptation of predictive models in response to prediction errors; therefore, it is hypothesised that depth of language comprehension will be modulated by both alignment and aperiodic slope. To explore this, 30 participants (23F, 1 not reported; mean age: 22.2 years [SD:4.4]) listened to 12 short stories (3 genres, audio-visual presentation) while their electroencephalogram (EEG) was recorded. Comprehension was tested via 6 multiple choice questions per story. An additional combined analysis, including a reanalysis of 40 audio- modality participants, provided evidence across both modalities that comprehension was improved for more surprising stories. Further, when considering inter-individual differences, the relationship between predictability and comprehension was shown to be modulated by both alignment and aperiodic activity. Comprehension of unexpected stories (as measured by N400 amplitudes) was improved only lower aligned, steeper aperiodic slope individuals. This finding is considered a reflection of complementary processing strategies which are weighted towards incoming stimuli, increasing the likelihood of model updating and therefore resulting in improved comprehension of unexpected stories.

neuroscience↗

bioRxiv2025

A neurophysiological alignment metric reveals a supportive role of unexpected stimuli in naturalistic language comprehension

Individuals use language every day to communicate their thoughts, emotions and expectations to those around them. Communication also incorporates receiving continuous and complex streams of information, not all of which is easily predictable. The memory literature suggests that this unexpected information may be processed more effectively when an individual possesses an adequate schema of the local context. We propose that, in language comprehension, we can determine the presence of a relevant scheme via an alignment metric, which compares an individuals brain response to language (N400 amplitudes) with an expected response as determined by the probabilistic contingencies of the current context (surprisal). When alignment is higher, an individuals internal model of the world is assumed to closely mirror the environment, constituting an effective schema. The present study sought to explore how individuals process unexpected information and whether successful comprehension is related to the alignment of internal predictive models to the external environment. It was hypothesised that higher alignment would support better comprehension of unexpected information than lower alignment. 40 participants (27F; mean age: 24.6 years [SD: 5.94]) listened to 12 short stories (3 genres, audio presentation) while their electroencephalogram (EEG) was recorded. Comprehension was tested via 6 multiple choice questions per story. A comprehension linear mixed-effects model (LMM) was computed for two regions of interest and two predictability metrics (N400 amplitudes and surprisal). A functional role of unexpectedness was demonstrated in all four models, where greater unexpectedness was related to higher comprehension scores. In one model we observed a significant interaction between alignment and average N400 amplitudes, indicating that comprehension was better for more unexpected stories when there was lower alignment to expected contextual probabilities. Our results suggest that individuals can utilise unexpected information to support language comprehension and that there are conditions where successful integration of this information is more likely. Contrary to our expectations, lower alignment to the current probabilistic conditions led to a greater capacity to utilise unexpected information. Future research should explore whether lower alignment reflects an individuals openness to integrate new information into existing schemas and how this impacts comprehension of unexpected language.

neuroscience↗