THE BRAIN, A PREDICTIVE MACHINE?: Cortical oscillations of anticipating and observing actions in ASD and typically developing people.

López Pigüi, Joana

Abstract

A fundamental human capacity is to construct predictive representations of upcoming events (the brain as a predictive machine). This is of special relevance within the social world, where the events that matter most are others’ actions, and whose accurate prediction/anticipation critically affects social success. The study of action prediction in social contexts is therefore a relevant issue in the Cognitive Neurosciences and Psychology, although it is a thoroughly complex and challenging task. A promising framework to study action prediction is the Mirror Neuron System (MNS), located in the sensorimotor cortex, which becomes active during both the execution and observation of actions. There has been a lot of speculation about the functional significance of the MNS. One interpretation, which will be pursued in the current studies, is that it is involved in the automatic understanding of others’ actions, i.e. an ‘experiential’ understanding ‘from within’. Traditionally, the MNS has been thought to respond only reactively, not predictively, when observing actions. However, recent single-cell studies in monkeys support a predictive role for the MNS. That is, provided contextual cues allow them to predict the upcoming action.
There is some intriguing evidence for an action anticipation impairment in autism spectrum disorder (ASD). Studies with ASD children suggested that, crucially, the chaining of the subsequent acts that together make up an action, is impaired. This motor chaining is crucial because it allows one to ‘take a peek into the future’ when the chain automatically unfolds like a row of falling dominoes. However, testing of adults with ASD has shown inconclusive results concerning their capability to predict actions, possibly reflecting their use of compensatory mechanisms. Aswell, the differences between different experiment conditions (age of the participants, type of stimuli, ecological validity, differences within the spectrum of autism) have made it difficult to compare results of mirror neuron functions in ASD people.
In this research we aimed to test the contentious idea that the ability to predict/anticipate other’s (upcoming) actions is underpinned by the concerted activation of ‘action-chains’ in the Mirror Neuron System, which has been suggested by some researchers to be impaired in ASD. To this aim, we collected the EEG data of adult participants with autism and of those high on autism traits, and neurotypical controls, while they observed sequences of actions between two interacting agents (either biological agents or non-biological agents). Each trial started with the still hands of the two agents depicted facing each other. The sequence of events included in some cases a predicting cue announcing that the first agent was going to perform an action (giving a card to the second agent) and the second agent was going to respond to that action (picking up the card that was given), or a unpredictable cue with no information on the incoming events (either first agent giving a card or not giving a card, second agent picking up the card or not picking up the card in case it was given to them). In parallel, there were non-biological stimuli, consisting of rectangular shapes (bars) rather than hands, “transferring” an object or not “transferring” it, with the same motion patterns and velocities as in the biological conditions. We measured the modulation of mu rhythms (8-13 Hz) at central, centroparietal and parietal areas, as a signature of MNS activity. Crucially, mu suppression was recorded not only during the performance of biological and non-biological motions, but also during the period preceding the motion, after the prediction cue was shown. Additionally, we measured the activity of occipital alpha in the occipital electrodes to compare such alpha band activity with mu rhythm in sensorimotor area.
We found that both experimental participants (those with autism/high autistic traits) and control participants (neurotypical) showed mu suppression during the time windows when an action was performed (either the action of the first or of the second agent for both biological and non-biological stimuli) without differences. We also found that prediction has a marginal effect in the first anticipation phase (either biological or non-biological) or no effect in mu oscillations during the second anticipation of an action. Moreover, differences between predictable and unpredictable conditions or between action and no action conditions were found only in typically developed participants. High autistic participants (experimental group) did not show differences between predictable and unpredictable contexts, with even greater mu desynchronization in some unpredictable conditions. The same pattern was found in the difference between action and no action contexts: high autistic trait groups did not show such difference, sometimes desynchronizing mu band even more in the prediction of no action conditions in the mu band.
This research hopes to establish how MNS interacts to produce a mechanism enabling action prediction/anticipation, which challenges the current MNM interpretation. It would help to understand joint actions and automatic action understanding, which form the bedrock of social interaction and education. Gaining an understanding of the characteristics of ASD/autistic traits is essential in comprehending how individuals on the spectrum read, process, and interpret social cues, particularly in relation to anticipating future events.

Citation

López Pigüi, J. (2025). THE BRAIN, A PREDICTIVE MACHINE?: Cortical oscillations of anticipating and observing actions in ASD and typically developing people. (Thesis). University of Hull. https://hull-repository.worktribe.com/output/5292359

• Thesis Type: Thesis
• Deposit Date: Jul 31, 2025
• Publicly Available Date: Aug 5, 2025
• Keywords: Psychology
• Public URL: https://hull-repository.worktribe.com/output/5292359
• Additional Information: Psychology; Faculty of Health Sciences; University of Hull
• Award Date: Jun 11, 2025