Mild Head Injury

     Glenn Mason-Riseborough (5/7/1998)

It is often the case that the problems associated with mild head 
injuries are overlooked.  This is because there are often no 
significant visible signs and it can be difficult to recognise and 
measure the effects of the injury, and therefore recognise if and 
when the person is fully recovered.  This essay will discuss some 
of the effects of mild head injury and a few of the measures used 
in assessment.  For clarity it will be divided into three sections. 
The first will discuss the cognitive, social, personality and 
behavioural effects of mild head injury.  Secondly, this essay will 
discuss the measures that can be used to assess the cognitive and 
behavioural effects of closed head injury and the rationale for 
using them.  Thirdly, the importance of gathering qualitative as 
well as quantitative information when assessing the effects of 
closed head injury will be discussed.

The effects of mild head injury
Gronwall, Wrightson, and Waddell, (1990) discuss in depth many 
of the effects that a person with mild head injury will experience.  
They categorise these as:
Fatigue:  This can often be the most debilitating effect of 
mild head injury.  The person finds it difficult to perform long or 
intensive activities because he tires far quicker.  He often sleeps 
more frequently and for longer periods, but may still wake feeling 
tired or may feel tired within a very short time.  Even normally 
relaxing activities such as watching television may be fatiguing.
Poor concentration and attention: This can be divided 
into three types of attention deficits.  A mild head injury patient 
may have focused attention deficits.  He may find it difficult to 
concentrate on a single task at the exclusion of other distracters 
in the environment.  Additionally, his divided attention may be 
affected.  In this case, he finds it difficult to complete two or 
more tasks simultaneously.  Thirdly, his attention span is 
affected.  The patient may find it difficult to work continuously 
on a task for a long period of time.
Memory problems: All parts of the memory process can 
be affected.  Often the patient will have retrograde amnesia (of 
any length of time) or post-traumatic amnesia (again this may last 
any length of time).  Any or all of immediate memory, short term 
memory and long term memory may be affected.  However, 
Lezak (1995) notes that many apparent memory problems may 
be due to attentional or retrieval deficits.
Lack of insight: The patient suffering from mild head 
injury may deny some of his problems and deficits from the 
injury, or focus on one symptom and not on others.  
Additionally, he may be unable to appreciate other peoples’ 
responses and may thus exhibit inappropriate actions in some 
social situations.
Slowed reactions: The patient may be unable to perform 
tasks (both physical and mental) as quickly or efficiently as he 
could before the accident.  Lack of coordination, and general 
physical weakness may also be noticeable.
Headaches: Patients suffering from mild head injury often 
suffer from headaches after the injury.  These may be related to 
stress or fatigue.
Emotional ups and downs: The emotions of the patient 
are often effected after a head injury, and he may suffer from 
extreme mood swings.  Feelings of elation and depression are not 
uncommon, and periods of objectivity and distancing may also 
occur.  Additionally, the patient may be unable to gauge the 
emotional reaction of others.  The patient may also be more 
irritable and may not be able to control his temper.
Changes in sexuality: The patient may suffer from 
impotence.  He may also behave in sexually inappropriate ways, 
and as mentioned above, may be unaware of his socially 
inappropriate behaviours.
In addition the patient may be sensitive to light, noise and 
alcohol (Fernando, 1998).  He may also suffer from epileptic 
seizures or have dizzy spells (Gronwall, Wrightson, & Waddell, 
1990).  There may be lesions in any area of the brain, producing 
for example, deficits in language or visual (or other sensory) 
recognition.  Lezak (1995) states that it is common for the 
patient to exhibit communication or perceptual difficulties.  
Fernando (1998) notes that these problems generally dissipate 
within three months after a mind head injury, however, for some 
patients it may take much longer.

Measures used to assess the effects of closed head injury
Numerous tests can be used to assess many of the typical effects 
of closed head injury as given in the previous section.  This 
section will examine a few of the more common tests available 
and the rationale for using them.  Gronwall (1977) states that in 
mild cases of closed head injury there is usually no detectable 
neurological evidence of injury.  However, the patient often 
complains of many of the symptoms given above.  Thus, there is 
a requirement for an objective measure of the severity of the 
injury and symptoms, and what (if any) recovery is taking place.  
The tests in general are used for a number of purposes 
(Fernando, 1998).  They provide information to assist in 
decision-making for rehabilitation – what are the deficits to be 
targeted, and is the current rehabilitation program assisting in 
recovery?  Secondly, the tests indicate if and when the patient 
should return to work and to what extent should his return be – 
full time, part time, reduced responsibilities etc.  Thirdly, the 
tests are used to indicate the extent of the deficits, the areas 
where the patient may have difficulty coping in everyday life, and 
the type of assistance (financial or otherwise) which may need to 
be provided.  Typically, a battery of tests is administered to cover 
the many possible problem areas and deficits.  No one test may 
be considered sufficient, and as Anastasi and Urbina (1997) note, 
there may be areas of duplication of function within the battery.  
Some of the more commonly used tests are:
Paced Auditory Serial Addition Task (PASAT) 
(Gronwell, 1977): The patient is required to listen to a series of 
numbers, add the last number to the previous number and record 
the result.  The numbers are read out at progressively faster 
speed for each respective trial.  This task is used to test the rate 
of information processing.  It assesses ability to work at speed, 
attention, and fatigue.  There is a significant practice effect 
between the first and second test administration, however, after 
this the effect is negligible.  Thus, the test is useful in measuring 
the recovery of the patient over a period of time, and can be used 
to indicate when the patient is ready to return to work.
Wisconsin Card Sorting Test: The patient is given a pile 
of cards and asked to sort them into groups according to a 
certain rule (colour, shape, number) one card at a time.  The 
examiner indicates whether each card was placed in the correct 
pile according to the current rule (which is changed without 
warning) and errors are recorded.  This test is useful in the 
assessment of cognitive flexibility – a large number of 
perceveration errors may indicate frontal lobe damage.  Memory 
may also be assessed using this test (Fernando, 1998).
In addition, general intelligence tests may be administered 
to patients with closed head injuries (eg WAIS-R, WISC-III) to 
measure academic and intellectual problems.  However as Lezak 
(1995) notes, often head injury patients can achieve adequate 
results in these general tests of intelligence but still suffer from 
memory deficits or slowed processing abilities.  Fernando (1998) 
states that there is often impairment on the Performance subtests 
as opposed to the Verbal subtests.  The results from individual 
subtests may also be useful in assessment, for example Digit 
Span tests immediate memory.  Other tests that may be used are 
Trail Making Test (attention), Symbol Digit Modalities Test 
(attention), Oral Word Fluency (verbal memory, retrieval and 
cognitive flexibility), Tower of London (problem solving), Rey-
Osterreith Complex Figure (visual memory), Benton: Visual 
Retention Test (visual memory), Wechsler Memory Scale – 
Revised (memory), California Verbal Learning Test (verbal 
memory), and Learning Efficiency Test (verbal memory).

The importance of qualitative data
The tests discussed in the previous section provide vital 
quantitative data in the assessment of closed head injury, 
however, it is important not to take these results in isolation.  
Fernando (1998) notes that the favourable conditions of a test 
environment may compensate for any functional deficits.  
Attentional deficits may not surface in a tidy, minimalist 
environment.  Quantitative data may not show evidence of the 
patient’s fatigue, as tests are generally relatively short and 
sessions are structured to maximise the patient’s potential.  The 
patient’s executive functioning requirements are minimised with 
clear test instructions.  Stress is relieved with the support and 
encouragement of an understanding examiner.  Pre-injury data is 
often not available so pre-injury skills and knowledge is not 
considered and comparisons are difficult.  Thus, qualitative 
information is often invaluable.  Interviews with the patient, 
family, friends and acquaintances provide important background 
and historical information.  It can also provide information on 
how the patient is coping outside the test environment – at home, 
work etc.  Observations of the patient during the tests may 
provide information on such problems as fatigue, stress, 
attention, perseverance and effort in responding, consistency, and 
previous knowledge.  Behavioural checklists which are filled out 
by family and acquaintances also provides information on how 
the patient is responding – are their behaviours appropriate in 
given situations, and have their behaviours changed noticeably 
since the accident?

Conclusions
After initial recovery from a mild head injury, the patient may 
suffer from many effects and deficits that generally dissipate with 
time (but not always).  These may include fatigue, poor 
concentration and attention, memory deficits, lack of insight, 
slowed reactions, headaches, emotional and sexual problems, 
sensitivity to light, noise, or alcohol, epileptic seizures, dizziness, 
and language or sensory deficits.  A battery of tests provides 
important quantitative information for many of these problems.  
There are many tests available that test specific areas that may be 
effected by closed head injury.  These tests often overlap and it is 
important to use a number of different tests to build a picture of 
the range and extent of the deficits.  This knowledge then assists 
in the rehabilitation and reintegration of the patient into society 
and work.  In addition to quantitative information, qualitative 
information also provides an important role in the assessment of 
the effects of a closed head injury.  Interviews, observations, and 
behavioural checklists all provide additional information that may 
be used in assessment.


References:
Anastasi, A., & Urbina, S. (1997). Psychological testing. 7th edn. 
Prentice-Hall.

Fernando, K. (1998). Lecture notes for University of Auckland 
paper 461.301.

Gronwall, D., Wrightson, P., & Waddell, P. (1990). Head injury. 
The facts. A guide for parents and care-givers. Oxford: 
Oxford University Press.

Gronwall, D. (1977). Paced auditory serial additional task: A 
measure of recovery from concussion. Perceptual motor 
skills, 44, 367-373.

Gronwall, D., & Wrightson, P. (1981). Memory and information 
processing capacity after closed head injury. Journal of 
neurology, neurosurgery, and psychiatry, 44, 889-895.

Lezak, M. (1995). Neuropsychological assessment. 3rd edn. 
Oxford: Oxford University Press.