Good cognitive capacity can aid recovery from a brain injury

In Finland, 15,000–20,000 new cases of brain injury are diagnosed annually. As many as half of brain injury patients develop long-term symptoms that impair their functional capacity and everyday life. 

Recovery from a brain injury is different for everyone and influenced by many factors such as the severity of the injury, age, and genetic traits. A study carried out at HUS reveals that the patient’s pre-injury cognitive capacity, the ability to process information, solve problems and perceive the environment, can significantly influence post-injury functional outcomes.

Previous studies have indicated that a higher pre-injury cognitive capacity protects the patient against after effects of brain injury. Register-based research has also observed that a weak pre-injury cognitive capacity is connected to a higher risk of sustaining a brain injury. However, measuring pre-injury cognitive capacity has been challenging as patients’ cognitive functioning is generally only assessed after the brain injury. 

Test results from the Finnish Defence Forces and data from the Brain Injury Registry opened up a new research opportunity  

The study utilized the test results Finnish Defence Forces’ P1 “basic test” which measures cognitive capacity in all individuals entering military service in Finland. Researchers combined test results from 1982–2015 with Brain Injury Registry data collected by Helsinki University Hospital in 1997–2020. 

The dataset included 377 male patients whose cognitive capacity had been measured prior to injury and whose recovery was assessed six months after traumatic brain injury using the Glasgow Outcome Scale. The results showed that a higher test result was associated with better recovery. Additionally, the test scores of those who had sustained a brain injury were, on average, lower than those of the control group. 

“Our results emphasize the significance of cognitive capacity both in brain injury prevention and rehabilitation. A good cognitive baseline can protect the patient against the after effects of brain injury and promote recovery,” summarizes doctoral candidate Wivi Taalas, who is conducting research at HUS under the guidance of neurosurgeons, Associate Professors Rahul Raj and Jari Siironen. 

Link to the research article:
The Role of Preinjury Cognitive Function in Future Traumatic Brain Injury and Functional Recovery. Published online October 16, 2025, in American Academy of Neurology’s medical journal Neurology.
 

In a university hospital, research is part of the treatment: we continuously evaluate and develop care based on scientific research evidence and patient experience. At HUS, we conduct close research collaboration with the Faculty of Medicine at the University of Helsinki. We publish approximately 2,400 peer-reviewed research articles) annually, which we highlight in our newsfeed.

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