During my MSc project, I used EEG to explore the electro-cortical correlates of multisensory integration in autism spectrum disorder. You can find more information on my MSc thesis here Past and current research projects are as follows:
Multisensory Integration in Autism
Abnormalities in sensory processing have been reported in individuals with autism spectrum disorder (ASD) in all sensory modalities. Along with unimodal deficits, there is mounting evidence for a deficit in assimilating information across modalities, or multi-sensory integration (MSI), especially in affect perception.
- Though the original objective of the study was to compare affective MSI in ASD and controls, due to time and technical constraints, only controls were tested.
- A reaction time, forced choice, categorization paradigm was used: Event-Related Potentials (ERPs) were recorded simultaneously while participants were asked to distinguish between dynamic stimuli depicting fear or disgust emotions; presented either auditorily (non-verbal), visually, or audio-visually. Results demonstrated a visual dominance in processing of emotions.
- ERPs were more sensitive in identifying neural correlates of affect perception.
Functional Specificity and Automatic Imitation
Humans show an involuntary tendency to copy other people’s actions. Although automatic imitation builds rapport and affiliation between individuals, we do not copy actions indiscriminately. Instead, copying behaviors are guided by a selection mechanism, which inhibits some actions and prioritizes others.
- To date, the neural underpinnings of the inhibition of automatic imitation and differences between the sexes in imitation control are not well understood.
- Previous studies involved small sample sizes and low statistical power, which produced mixed findings regarding the involvement of domain-general and domain-specific neural architectures.
- Here, we used data from Experiment 1 ( N = 28) to perform a power analysis to determine the sample size required for Experiment 2 ( N = 50; 80% power).
- Using independent functional localizers and an analysis pipeline that bolsters sensitivity, during imitation control we show clear engagement of the multiple-demand network (domain-general),but no sensitivity in the theory-of-mind network(domain-specific).
In summary, neurocognitive models of imitation require revision to reflect that the inhibition of imitation relies to a greater extent on a domain-general selection system rather than a domain-specific system that supports social cognition.Resources for this project: scripts and data available online at: link here.
Automatic Imitation and Cognitive Load
Automaticity has been argued to be a core feature of the mental processes that guide social interactions, such as those underpinning imitative behaviours. To date, however, there is little known about the automaticity of imitative tendencies.
- In the current study, we used a finger movement stimulus-response compatibility task to index processes associated with controlling the urge to copy other people’s actions.
- In addition, we manipulated the level of load placed on a secondary cognitive task to test if there is a capacity limit in the systems that filter distractor finger movement stimuli.
- Across three experiments, we showed that whether letter strings (Exp. 1), faces (Exp. 2) or hand postures (Exp. 3) are held in working memory, there was no impact on compatibility effects in the main task.
Therefore, in the sense of persisting in the presence of a demanding cognitive load this type of imitation behaviour can be considered automatic
Automatic Imitation: fMRI Meta-Analysis
Humans copy other people without their conscious awareness, a behaviour known as automatic imitation. Although automatic imitation forms a key part of daily social interactions, we do not copy other people indiscriminately.
- Instead, we control imitative tendencies by prioritising some actions and inhibiting others.
- To date, neuroimaging studies investigating the control of automatic imitation have produced inconsistent findings. Some studies suggest that imitation control relies on a domain-specific neural circuit related to social cognition (the theory-of-mind network).
- In contrast, other studies show engagement of a domain-general neural circuit that is engaged during a diverse range of cognitive control tasks (the multiple demand network). Given the inconsistency of prior findings, in the current paper we avoided problems associated with interpreting individual studies by performing a meta-analysis.
- To do so, we used a multi-level kernel density analysis to quantitatively identify consistent patterns of activation across functional magnetic resonance imaging studies investigating the control of imitation.
- Our results show clear and consistent evidence across studies that the control of automatic imitation is guided by brain regions in the multiple demand network including dorsolateral frontoparietal cortex.
- In contrast, there was only limited evidence that regions in the theory of mind network were engaged.
- Indeed, medial prefrontal cortex showed no consistent engagement and right temporoparietal junction engagement may reflect spatial rather than imitative control.
Consequently, neurocognitive models of imitation need updating to place more emphasis on domain- general control mechanisms, as well as to consider more complex organisational structures of control, which may involve contributions from multiple cognitive systems.