Mild traumatic brain injury

Concussions

Mild traumatic brain injury (mTBI), or concussion, is the result of a minor head injury. This potentially results in neural alterations which can cause long-term cognitive impairment, known as post-concussive syndrome. Many patients are admitted to the emergency departments every year for a mTBI, while less than half of them receive a prescription for a brain scan, bedrest or pharmacological treatment, and the majority are sent home without follow-up, emphasizing the lack of appropriate care provided following head injury.

A recent advancement in the field has highlighted the causal role of mTBI on cognitive impairment, but only a few studies investigated the impact of a concussion on (motor) learning. Patients, often students, present various motor deficits such as slower reaction time, longer preparation time to perform a task (Zahn and Mirsky 1999) or reduced movement velocity (De Beaumont et al. 2009). The underlying mechanism of motor learning deficits after concussion is a novel field that merits exploration. The rationale behind this is that mTBI is associated with sleep disturbances (Gosselin et al. 2009), and sleep is crucial for memory consolidation. Recently, a link between poor sleep quality following a concussion and both greater symptom severity and longer recovery time has been demonstrated both in adults and pediatric populations (Bramley et al. 2017; Chung et al. 2019). Yet the impact of sleep on motor memory consolidation following a brain injury is simply unexplored in the current literature. Dr. Aurore Thibaut (co-director of the Coma Science Group) and her team aim to study how sleep can influence functional and cognitive recovery of young adults who have suffered from a concussion. We are running different projects to enhance the current knowledge of and improve concussion management in sport professionals, with the collaboration of ReFORM (Réseau Francophone Olympique de la Recherche en Médecine du sport), Prof. Jean-François Kaux (head of the department of Physical & Rehabilitation Medicine and Sport Traumatology, University Hospital of Liège), Dr. Suzanne Leclerc (director of the Sports Medicine Clinic, INS Québec) and Dr. Géraldine Martens (scientific coordinator of ReFROM). We also study biomarkers of poor and good outcomes following a concussion using EEG and fMRI, including polysomnography and actimetry to objectify sleep quality.

COMMON SYMPTOMS in the first few hours and days after mTBI:

Physical symptoms

  • Headache

  • Nausea or vomiting

  • Fatigue or drowsiness

  • Problems with speech

  • Dizziness or loss of balance

 

Sensory symptoms

  • Sensory problems, such as blurred vision, ringing in the ears, a bad taste in the mouth or changes in the ability to smell

  • Sensitivity to light or sound

 

Cognitive, behavioral or mental symptoms

  • Loss of consciousness for a few seconds to a few minutes

  • No loss of consciousness, but a state of being dazed, confused or disoriented

  • Memory or concentration problems

  • Mood changes or mood swings

  • Feeling depressed or anxious

  • Difficulty sleeping

  • Sleeping more than usual

Moderate to severe traumatic brain injuries (can include any of the signs and symptoms of mild injury) within the first hours to days after a head injury:

Physical symptoms

  • Loss of consciousness from several minutes to hours

  • Persistent headache or headache that worsens

  • Repeated vomiting or nausea

  • Convulsions or seizures

  • Dilation of one or both pupils of the eyes

  • Clear fluids draining from the nose or ears

  • Inability to awaken from sleep

  • Weakness or numbness in fingers and toes

  • Loss of coordination

 

Cognitive or mental symptoms

  • Profound confusion

  • Agitation, combativeness or other unusual behavior

  • Slurred speech

  • Coma and other disorders of consciousness

For more information visit www.mayoclinic.org