Types of Cognitive Functions
There are several major areas of cognitive function that may sustain impairment following a head injury or other traumatic injury: memory and learning, language and communication, judgment and perception, spatial skills, and behavioral and emotional responses.
Memory and Learning
These are the most common areas of difficulty following a brain injury. You might experience a loss of previously learned information, but the more common symptom is difficulty organizing and learning new information.
You might notice the problem as an inefficiency with new learning (taking more time or attempts to learn new tasks of information). Depending on the extent of your injury, you may experience
- diminished information recall,
- rapid loss of new information without the opportunity to practice, or
- diminished recall of recent events.
Language and Communication
You may also experience impairment in language or communication. Injury to the left temporal lobe of the brain interferes with understanding language and may prevent you from being able to clearly express your thoughts.
Impairment in this area can include
- inefficient or loss of word retrieval,
- uninhibited choice of words, or
- "tip of the tongue" phenomenon.
Problems Expressing Language
There is, of course, a motor function involved in language. If that motor function is impaired, you may find yourself
- having difficulty saying the word,
- having difficulty generating words when asked for a specific response,
- exhibiting inefficient speech (talking around a topic),
- experiencing problems with verbal fluency.
These are all considered to be expressive language problems, where the difficulty is in producing language.
Problems Understanding Language
An impairment in receptive language causes difficulty in understanding language or the meaning of words. This can take several forms:
- difficulty following simple or complex sentences or instructions,
- difficulty interpreting someone's meaning because you can't interpret tone of voice or facial expressions,
- problems such as timing of speech or proper intonation.
These difficulties are called "paralinguistic" features of language.
Problems with Judgment and Perception
Another area of cognitive function is judgment and perception. Impairment in this area may take the form of misjudging your strengths or weaknesses.
Unrealistic judgment of your strengths or weaknesses can lead you to attempt tasks that are too difficult.
Further, you may misinterpret the actions or intentions of others. For example, physical closeness by a same sex peer may be interpreted as aggression. Similar closeness by an opposite sex peer may be misperceived as flirtation.
These kinds of misperception can lead to a wide range of inappropriate behavior, including embarrassing or insulting comments. Judgment/perception impairment can result in embarrassments, misunderstandings, and at worst, it may lead to physical harm.
Another cognitive impairment that can lead to physical harm is an impairment in your spatial skills. This can cause you to misjudge your step on stairs, or misjudge the distance between cars when driving.
Impairment in the parietal lobe of your brain may lead to problems with spatial ability. Small deficits in the front parts of the parietal lobes can lead to numbness on the opposite side of the body. Larger injuries may end your ability to perform sequenced tasks or remember right-left orientation.
With this type of cognitive impairment, people who delay treatment when they first notice symptoms can end up hurting themselves.
Behavioral and Emotional Impairment
Finally, cognitive functions also regulate behavioral and emotional responses. Impairment in behavioral or emotional function can result from damage to the frontal lobe of the brain.
Emotional problems may be a direct result of damage to the brain, or a result of the person's frustration in trying to do things after a cognitive impairment. Typical emotional reactions indicating cognitive impairment include
- mistrust of others
- social withdrawal
Emotional reactions that are linked directly to damage in certain areas of the brain include
- socially inappropriate comments or actions,
- unawareness of deficit,
- misperception of the intentions or actions of others,
- under (hypo) or over (hyper) states of arousal,
- diminished motivation and impulsiveness.
Common behavioral difficulties observable in individuals with a cognitive impairment include
- physical aggression/oppositional behavior,
- impulsive behavior,
- diminished motivation,
- failure to comply with instructions,
- irritability toward others.
Of course, it is important to assess the context in which these behaviors or emotional reactions occur. Recording the factor(s) present at the time of the reaction may be important in proper diagnosis and management.
When an inappropriate emotional reaction occurs, observe the time of day, the people present, noise levels, and the tasks the person is attempting. Understanding predictors of inappropriate emotion or behavior can assist family and caregivers in coaching proper behavior. The injured person then has a better chance to achieve their goals.