Language Processing After Trauma

A study of recovery from severe traumatic brain injury conducted between the University of Birmingham and the Queen Elizabeth Hospital, Birmingham.

Note: This study is now closed. A full summary is provided below.

What was our study about?

The main aim of our study was to find new ways to more accurately predict how well people will recover after severe brain injuries.

Specifically, we investigated whether the way that people’s brains respond to hearing speech can help to predict how well they will recover while in the intensive care unit. Our study focused on people who were unresponsive after a traumatic brain injury and who weren’t being given any sedative medication at the time, as these are the people for whom it is most difficult to predict outcome currently

Why was our study important?

If we can make more accurate predictions about how well people will recover after severe brain injuries, then we can help families and clinical teams make the best possible treatment decisions during a very difficult period after injury.

 

What did our study involve?

To achieve our aim, we recorded brain activity using electroencephalography (EEG), which is a set of electrodes placed on the scalp that record the tiny electrical signals generated by the brain’s billions of cells. We recorded EEG while our participants were resting quietly and while we played them spoken sentences through earphones.


We recruited 28-participants onto our study between April 2018 and September 2019 from the Queen Elizabeth Hospital, Birmingham.

What are the results of the study?
Key result 1: Brain responses to speech help predict patients’ levels of recovery
 

Our participants’ data showed us that unresponsive people in the intensive care unit are more likely to go on to make a good recovery over the 6-months after their severe brain injury if their brains appear to be processing the meaning of what they are hearing. This result suggests that measuring brain activity while people listen to speech in the intensive care unit could be a new way to help make more accurate predictions about each individual person’s chances of recovery.


It’s important to say that we don’t know that this means that those participants had a conscious experience of understanding what they were hearing at the time. Rather, what we can say is that the brains of some participants were able to follow the structure of spoken sentences, which is something that people who are asleep, for example, cannot do, and that those participants were more likely to make a good recovery.


The next step for us now is to conduct a large-scale study of this same effect with people recruited across multiple hospitals in the UK. If we see this same effect again, then we can start to make it part of standard assessment in the intensive care unit.

 

Read the published scientific paper about this result to find out more.

Key result 2: What the brain does at rest helps predict patients’ levels of recovery


As part of the same study, we also recorded a short 5-10-minute period of EEG while our participants were lying quietly in bed in the intensive care unit. This recording can tell us about how different parts of the brain are communicating with one another while the person is resting. Our data from this study showed that a simple measure of brain activity taken from this EEG can improve the accuracy of predictions about levels of recovery. We think that this measure, known as mean relative alpha power, tells us how well two key parts of the brain can communicate with one another – the thalamus and the cortex. If communication between those regions is still happening in the intensive care unit, then those individuals have a higher chance of recovery. 


As with the result above, our next step is to verify this result in a large group of individuals across multiple hospitals in the UK before we work to make it part of standard clinical assessment after severe brain injury.
 

Read the published scientific paper about this result to find out more.

Summary

The data provided by our participants and their consultees have revealed two new important directions for clinical practice in the intensive care unit. These directions may increase the accuracy of predictions about recovery, and make sure that families, caregivers, and doctors have the best available information when making clinical decisions in this difficult period.

How can I find out more information?

If you would like more information about the study, then please get in contact with us here.