Examining multisensory processing of emotional signals in PTSD
Research type
Research Study
Full title
Examining multisensory processing of emotional signals in Post-traumatic Stress Disorder
IRAS ID
270091
Contact name
Naomi Heffer
Contact email
Sponsor organisation
University of Bath
Duration of Study in the UK
1 years, 8 months, 31 days
Research summary
Understanding emotions is central to human interaction, and difficulty interpreting the emotions of other people has been linked to social and emotional difficulties in some psychiatric populations. Sensory anomalies have been demonstrated in individuals with post-traumatic stress disorder (PTSD), but only in studies focusing in on one sensory modality. Emotions are normally expressed and perceived via multiple senses, which means that in order to fully understand whether everyday emotion processing is altered in individuals with PTSD, it is necessary to investigate how emotions are recognised using multiple senses. This project will use psychophysics and electroencephalography (EEG) to assess how individuals with and without PTSD and exposure to traumatic life experiences combine auditory and visual emotional information. To this end we have developed a task where participants make emotion judgements about emotional faces and voices. We plan to measure performance on this task, along with participant heart rate, skin response and electrical brain activity and will compare these measurements between individuals in three groups: a group of PTSD patients, a group of individuals who have been exposed to trauma but not developed PTSD, and a group of individuals who have never been exposed to trauma. The main aims of the project are to determine whether (1) individuals with PTSD are more likely to weight negative or threatening cues more heavily in ambiguous multisensory displays (which would replicate what has been found for high trait anxiety), (2) allow us to link multisensory processing alterations in PTSD to a specific stage in the information processing stream using EEG, and (3) to construct a mathematical model based on behavioural, physiological and electrophysiological indicators of multisensory processes that can discriminate between individuals with and without PTSD.
Lay summary of study results: Understanding emotions is central to human interaction, and difficulty interpreting the emotions of other people has been linked to social and emotional difficulties in individuals with mental health conditions, such as post-traumatic stress disorder (PTSD). Emotions are normally expressed and perceived via multiple senses (e.g., facial expression and voice tone) but previous research in PTSD has typically only focused on visual processing. This project used a brain imaging technology called electroencephalography (EEG) to investigate how individuals with and without PTSD combine information from hearing and vision when making emotional judgements. To this end, we developed a task where participants had to make emotion judgements about happy, sad and angry faces and voices.
The final analysis of the full dataset has not yet been completed as the data analyses and publication write-up are ongoing, however a preliminary analysis of the data comparing participants with and without a diagnosis of PTSD shows some interesting potential results. There were no differences in accuracy between participants with and without PTSD when judging faces and voices as being emotional or neutral, although participants with PTSD were consistently slower at making these judgements, suggesting that these individuals may need more time to process complex emotional information. There were also differences between participants with and without PTSD in terms of their brain activity, but specifically when processing happy faces and voices, and not for information relating to the other emotions. These differences in brain activity suggested that there might be less unconscious and automatic processing of positive information for individuals with PTSD, which is compensated for by increased conscious and effortful processing of positive information. Overall, the findings so far suggest that individuals with PTSD may need to put in more time and effort to process complex emotional information (particularly positive information), although it will be necessary to complete the final analysis with the full dataset before any conclusions are made.
REC name
North East - Newcastle & North Tyneside 2 Research Ethics Committee
REC reference
20/NE/0050
Date of REC Opinion
12 Feb 2020
REC opinion
Favourable Opinion