Buried in the middle of an e-mail from my sister was news I had hoped never to receive-"By the way, did you hear that Mark fell off his bike, hit his head, and has lots of stitches?"
Mark is my brother-in-law. I immediately switched from the sister role to the role of medical investigator, and peppered her with questions to learn more about the severity of his injury: "Was he wearing his helmet? Did he lose consciousness and if so, for how long? Was he confused? Did the MRI show anything? Has he returned to work?" Mark was lucky-the blow to his head did not result in any lasting cognitive or memory problems. He was back to work in a few days.
Many others are not as fortunate. Every year, about 500,000 civilians sustain a traumatic brain injury (TBI). The Centers for Disease Control and Prevention estimates more than 50 million people currently live with TBI-related disabilities in the United States. During times of war, this number swells. Unfortunately, no age group is spared although young men are more likely to be injured than women or members of other age groups.
A blow to the head can result in long-lasting motor, cognitive, communicative, and psychosocial disabilities. These disabilities range from mild to severe and act as significant barriers when trying to return home, to school, and to work. Speech-language pathologists are uniquely trained to manage these cognitive-communication disorders, as ASHA technical documents attest.
Unlike the common portrayal of memory loss in feature films, memory impairment after TBI typically reflects difficulty individuals have remembering recent events, not their identity or remote past. While some individuals with severe injuries may have forgotten parts of their past-called retrograde amnesia-it is much more common to have trouble remembering recent events or details, called anterograde amnesia. During the early stages of recovery when individuals have fleeting attention skills, it is quite common for individuals to be very confused. This confusion presents as impaired comprehension, inability to follow instructions, disorganized discourse, confabulation, word substitutions, and even disrupted phonology. As attention improves, confusion subsides and individuals begin to form new memories, i.e., begin to learn.
Even after the "acute" recovery phase however, most individuals continue to be forgetful. They don't remember the details from stories or conversation, they have trouble remembering appointments the next day or tasks they need to plan for, they have difficulty remembering people's names, and they struggle to recall changes in procedures at work. These short-term memory problems are related to the injury.
The hippocampus, which is located just inside the temporal lobes, is where short, brief memories are formed and briefly stored while actively "waiting" to associate with other bits of information. The temporal and frontal lobes rest on the skull's boney shelf. Together, these lobes and their connections to other brain regions often are injured from direct or indirect blows to the head. Fortunately, injured individuals have other types of memory that remain intact, such as memory for procedures and routines. In treatment, SLPs should capitalize on these procedural memory skills when training the compensatory strategies.
Providing individuals with strategies does not guarantee that they will select the appropriate strategy for a given task or use it at the right time. What a person "does with what they have is more important than what they actually have" (Ylvisaker & Feeney, 2004). To make strategy decisions, individuals need to acknowledge or "know" that they have memory impairment and therefore have a need for the strategy.
Metamemory is thinking about your memory. "Meta" refers to one's ability to view, observe, and assess more basic cognitive processes…" (Kennedy & Coelho, 2005, p. 243). "Meta" can be applied to other systems, as in metacognition, metacomprehension, or metalinguistics. Strong evidence from many disciplines links meta processes to frontal lobe activity. Unfortunately, the areas of the brain that allow us to be "aware" are areas likely to be injured in a TBI. Thus, many individuals with TBI have dual disabilities-a memory impairment and metamemory impairment.
Three aspects of a meta system are important to understand, especially for SLPs, neuropsychologists, and other rehabilitation professionals working with individuals with brain injury. These aspects include autobiographical beliefs (also called self-awareness), self-monitoring, and self-control during activities. Autobiographical beliefs are opinions one holds about general skills. They are updated by ongoing experiences over a period of time. When recovering from TBI, most individuals become aware of physical impairments before gaining awareness of more subtle impairments such as attention and memory. The longer one lives with the disabilities associated with TBI, the more aware they become. But of course, there is tremendous heterogeneity in this population; some remain "unaware" for an extended time, whereas others' awareness emerges as they recover and stabilize over months and years.
Updating self-awareness of memory is related to memory for recent events. We need to be able to remember daily memory experiences (particularly memory failures) in order to reflect on these and update our general belief about our memory. For example, if people remember that they forgot about an appointment and missed it, they are more likely to think that their memory is not as good as it used to be. Thus, sufficient memory for daily events is necessary if individuals are going to become more realistic about their memory over time.
When individuals are accurate in predicting their memory, they are more likely to decide to use a strategy that could help them remember. These strategy decisions are called self-control. Consider, for example, if you are reading the new operations manual used at work and notice that many procedures have changed. Perhaps you realize that you may not remember these changes when you need them (self-monitoring). To prevent a memory failure, you decide to create a list of keywords for each procedure (self-control) and to keep it in your pocket (or paper or electronic planner) during work hours.
Thus, strategy decisions are linked to self-monitoring for tasks that are complex and non-routine. For repetitive everyday tasks, strategy decisions tend to be routine, without much conscious control. For a more complete description of the relationships between beliefs, self-monitoring, and self-control, see Kennedy and Coelho (2005).
From Kennedy, M. Managing Memory and Metamemory Impairment in Individuals with Traumatic Brain Injury. The ASHA Leader, 11(14), 8-9, 34-36. Reprinted with permission. www.asha.org.