Neuropsychological Effects of Head Trauma in College Athletes

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Neuropsychological Effects of Head Trauma in
College Athletes

• Anthony C. Santucci, Ph.D.
• Manhattanville College
• Purchase, NY

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Outline of Talk

• Brief review of neuroanatomy
• Sources of brain damage
• Collisions in sports
• Effects of collisions on the brain
• Concussions
• Description of recent study from my lab

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Anatomy of a Neuron
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Microstructure of a Neuron
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Meninges of the Brain
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Midline View of the Brain
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Sources of Brain Damage

• Vascular Accident (stroke)
• Hemorrhage bleeding in the brain
• Infarct brain damage due to deprivation of
  blood supply resulting from vascular constriction
  or obstruction (i.e., ischemia)
• Diseases
• Progressive neurodegenerative disorders
  (Alzheimers, Picks, or Parkinsons disease)
• Viral infection (e.g., spongiform encephalopathy)

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Sources of Brain Damage (cont)

• Penetrating Wounds or Open-Head Injuries (e.g.,
  gunshot, metal rod impalement, etc. often are
  sharp force trauma)
• Genetic Abnormalities (e.g., Huntingtons
  disease, etc.)
• Tumors (e.g., glioma, meningioma, etc.)
• Closed Head Injuries (i.e., Diffuse Axonal Injury
  -- axonal shearing rotational/gravitational
  force -- whiplash, or contusions caused by
  blunt force trauma)

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Definition of Closed Head Injury

• Closed Head Injuries biomechanical deformation
  of brain tissue
• Closed Head Injuries can be caused by
• a foreign object concussing the head, i.e., blunt
  force trauma or collision (e.g., with another
  persons head or body, hit by ball)
• the head being concussed against a rigid object,
  i.e., blunt force trauma (e.g., goal post,
  boards, etc.), or
• the head being subjected to a sudden severe
  rotational and/or gravitational force (e.g.,
  whiplash) most likely cause of Diffuse Axonal
  Injury (DAI) in traumatic brain injury

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Brain Vasculature as it Relates to Head Trauma
Bridging Veins
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Collisions in Contact Sports

• Participating in contact sports, especially
  football, ice hockey, gymnastics, wrestling,
  boxing, makes one vulnerable to a closed head
  injury especially that derived from collisions
  (e.g., football causes approximately minor head
  injuries in approximately 20 of its participants
  Cantu, 1998).
• Collisions involving the head in sports can occur
  in a variety of ways including

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Head-to-Ground
Head-to-Elbow
Back-to-Ground (reverberation)
Head-to-Shoulder
Head-to-Ground
Head-to-Body
Heading
Top-to-Ground(compression)
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Head-to-Head
Front-to-Side
Front-to-Top
Top-to-Side
Front-to-Front
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Blunt Force Trauma-Induced Contusions
Extensive blunt force trauma sustained in a
vehicle accident
The cerebral crest is especially vulnerable to
damage caused by blunt force trauma
Fall-induced blunt force trauma causing contra
coup injury
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Hematomas
Subdural hematoma
Epidural hematoma
Subarachnoid hematoma from contra coup injury
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Diffuse Cerebral Edema (i.e., swelling)
Edema producing widened gyri and narrower sulci
Acute closed cranial cavity edema producing
herniation (pushing through) of the hippocampus
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Boxing Diffuse Cerebral Edema Edema
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Neurocascade Events are Evidenced by Impact Trauma
Schematic Courtesy of UCLAs Brain Research
Institute
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Rotational Gravitational Force Injuries
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Diffuse Axonal Injury

• DAI frequently results from sudden
  acceleration-deceleration impact that produces
  rotational forces, most often causing white
  matter lesions
• DAI produces an anatomic metabolic cascade
• ? shearing of axons ? edema ? axoplasmic leakage
  ? disruption of axonal transport ? degeneration
  of the axon ? neuron death
• DAI is often undervisualized using current brain
  imaging techniques
• DAI is a frequent cause of persistent vegetative
  state morbidity

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Other Possible Effects Produced by Collisions

• Second-impact syndrome (SIS)
• Occurs when a second concussion is sustained
  while the athlete is still symptomatic and
  healing from a previous concussion. The second
  injury may occur from days to weeks following the
  first. Loss of consciousness is not required. The
  second impact is more likely to cause brain
  swelling and other widespread damage, and can be
  fatal. (Note, some authors contend this syndrome
  is the result of complications derived from
  Diffuse Cerebral Edema and, as such, should not
  be classified as a separate medical condition.)
• Intra-cerebral hemorrhage
• Bleeding that occurs within the brain that can
  affect neurological and mental functioning

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Effects of Concussions

• Posttraumatic amnesia (anterograde amnesia)
• Retrograde amnesia
• Mental Confusion Disorientation
• Headache
• Nausea/Vomiting
• Visual disturbance (blurred vision, double
  vision)
• Dizziness
• Slurred speech
• Drowsiness
• Loss of Consciousness

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Problem of Defining Concussion

• There is no widely accepted definition of
  concussion, especially that of Postconcussion
  Syndrome i.e., residual effects of concussion)
• Committee of Head Injury Nomenclature of the
  Congress of Neurological Surgeons
• Concussion is a clinical syndrome characterized
  by immediate transient post-traumatic
  impairment of neural functions, such as
  alteration of consciousness, disturbances of
  vision, equilibrium, etc. due to brainstem
  involvement.
• However, other definitions exists

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Other Definitions of Concussion

• Other definitions are based on
• Duration of unconsciousness
• Duration of post-traumatic amnesia
• Cantu (1986) based his definition on both
  duration of unconsciousness or amnesia

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Cantu (1986) (adapted from Cantu, 1998)
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American Academy of Neurology

• AAN defines concussion as a "alteration of mental
  status due to a biomechanical force affecting the
  brain." The AAN definition does not require a
  loss of consciousness. The AAN guidelines, break
  down concussion into three grades
• Grade 1 Transient confusion NO loss of
  consciousness symptoms clear in less than 15
  minutes.
• Grade 2 Transient confusion NO loss of
  consciousness Concussion symptoms or mental
  status abnormalities last longer than 15 minutes.
• Grade 3 Any loss of consciousness, either
  brief (seconds) or prolonged (minutes).

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5-Grade Classification System (athleticadvisor.com
)

• Grade 0
• results when the head is struck or moved rapidly
  characterized by a post injury headache and
  difficulty with concentration
• Grade 1
• athlete appears stunned no loss of consciousness
  (LOC) sensory difficulties resolve lt 1min
  bell-rung
• Grade 2
• characterized by headache cloudy senses gt I min
  but no LOC tinnitus, amnesia, irritability,
  confusion, or dizziness may be present
• Grade 3
• LOC lt 1 min not comatose same symptoms as grade
  2
• Grade 4
• Grade 4 concussions are characterized by LOC of
  greater than one minute. The athlete will not be
  comatose, and will also exhibit the symptoms of
  the grade 2 and 3 concussions

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Return-to-Play Decisions(Cantu, 1998)
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Alternate 3-Grade Return-to-Play System
(Familypracticenotebook.com)
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Rationale for Study

• Head trauma sufficiently severe enough to produce
  a diagnosable concussion would be associated with
  changes in neuropsychological function,
  especially that within the memory domain
• Assessed whether such neuropsychological
  alterations would be dependent upon
• Severity frequency of concussion
• Time since concussion

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Method

• Participants
• UG participants in contact sports lacrosse,
  soccer, ice hockey, /or field hockey with
  either
• A recent history of concussion (lt 2 yrs) (N5
  3M,2F)
• A non-recent history of concussion (gt 2 yrs)
  (N6 3M,3F)
• No history of concussion (N9 6M,3F)
• UGs who did not participate in a contact sport
  and who had no history of concussion (N8 5M,3F)

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Participant Demographics
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Materials Procedure

• General Concussion Reference Form
• Subject Questionnaire Form
• Repeatable Battery for the Assessment of
  Neuropsychological Status (RBANS Randolph, 1998)
• Postconcussion Syndrome Checklist
• Stroop Task

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Materials Procedure (cont)

• RBANS
• Uses standardized norms to assess five cognitive
  domains
• IMMEDIATE MEMORY
• DELAYED MEMORY
• VISUOCONSTRUCTIONAL/SPATIAL ABILITY
• LANGUAGE
• ATTENTION
• Each sub-scale score contributes to an OVERAL
  TOTAL SCORE

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Results on the RBANS
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Results on the Stroop Test
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Correlation Matrix for the two Athlete Concussed
Groups
p lt .05 p .10
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Correlation Matrix for the Athlete/Recent
Concussed Group
p lt .05
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Conculsions

• Recent heady injury is associated with
  alterations in neuropsychological function,
  especially that which lie in the memory domain
• These neuropsychological effects appears to
  resolve with time
• Provocatively, participation in contact sports
  may produce sub-clinical cognitive impairments in
  the absence of a diagnosable concussion
  presumably resulting from the cumulative effects
  of multiple mild brain trauma

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Limitations to the Research

• Small N
• Did not include football athletes
• Used UGs at a Division-III school
• Relied on self-report data for concussion
  information
• Did not have pre-injury data
• Used only one neuropsychological test

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Future Research

• We are presently looking more closely at whether
  concussed athletes show changes
• In EEG waves, esp. within the frontal and
  temporal lobes
• In spatial memory with altering levels of task
  difficulty
• On another neuropsychological test, this time
  assessing solely attention (d2 Test of Attention)

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Thank You