CHAPTER 15 This book describes the impact of cognitive impairments on the communication functioning of individuals following acquired brain injury. Cognition can be broadly described as mental activities or operations involved in taking in, interpreting, encoding, storing, retrieving, and making use of knowledge or information and generating a response (Ylvisaker & Szekeres, 1994). Examples of cognitive processes attributed to the frontal lobes include the ability to focus attention to stimuli, remembering and learning, organizing information, reasoning, and problem solving. In addition to specific cognitive processes, the frontal lobes mediate executive control of thought and behavior. Such executive functions include goal setting, behavior planning and sequencing, goal oriented behavior, and initiation and evaluation of behavior (Lezak, 1993). Baddeley (1986) coined the term “dysexecutive syndrome” to characterize the range of impairments that commonly follow frontal lobe injury (Baddeley, 1986). Executive functions impact on all aspects of our daily behavior, including our ability to communicate. This chapter will focus on approaches to taking executive functioning explicitly into account when treating communication difficulties after acquired brain injury. Executive functions are typically mediated by the frontal and prefrontal cortices (Stuss & Benson, 1984), and so the assessment and treatment approaches described in this chapter will be most relevant to populations who have damage in these regions. This is with recognition of the fact that executive functioning probably involves multiple component processes involving several brain regions working in concert (Keil & Kaszniak, 2002). Frontal injury can be focal, such as would occur with a stroke, or it can be diffuse, which is more typical of traumatic brain injury (TBI). Executive functioning can be compromised by disorders such as multiple sclerosis (O’Brien, Chiaravalloti, Goverover, & DeLuca, 2008), Alzheimer’s disease (Marshall, Capilouto, & McBride, 2007) and even from cerebellar damage due to the links to the frontal cortex via cortico-ponto-cerebellar networks (Schweizer, Levine, Rewilak, et al., 2008). Many of the strategies discussed in this chapter are drawn from the TBI research literature, given the preponderance of executive functioning deficits that may follow this type of injury. Nonetheless, the ideas presented here will be useful to managing communication problems that arise from other acquired frontal injuries. Executive impairment has been described as representing either a loss of drive or a loss of control that may translate into deficiencies (e.g., inertia, rigidity, poor conceptualization and planning) or excesses (such as disinhibition) of cognition and behavior (R. Tate, 1999; R. L. Tate, Lulham, Broe, et al., 1989). Inertia and rigidity can lead to a flat presentation, seeming disinterest in the conversation, and inability to generate and maintain topics. Alternatively, excesses can interfere due to frequent interruptions, disinhibited responses, swearing, and perseveration on topics. These inappropriate and disturbing communicative behaviors are difficult to manage, particularly when in a community setting such as a shopping center. The relationship between executive functioning and communication difficulties after TBI was first enunciated three decades ago. A. L. Holland (1982) was perhaps the first to ask the classic question “When is aphasia aphasia?” raising the idea that if people with TBI were labeled as aphasic they would, in turn, receive inappropriate treatment that would fail to take their cognitive impairments into account. At about the same time, other researchers recognized this interplay between cognition and language, leading to the introduction of the term cognitive-language disorder (Hagen, 1984; Kennedy & DeRuyter, 1991). The first work in this area examined the relationship between cognitive disturbances following TBI and psycholinguistic aspects of language (Hagen, 1984). The impairments of attention, memory, sequencing, categorization, and associative abilities were seen to result in an impaired capacity to organize and structure incoming information, emotional reactions, and the flow of thought. Such impairments, Hagen argued, caused a disorganization of language processes. Cognitive disorganization is reflected through language use that is characterized by irrelevant utterances that may not make sense, difficulty inhibiting inappropriate utterances, word-finding difficulties, and problems ordering words and propositions. Prigatano, Roueche, and Fordyce (1985) described nonaphasic language disturbances following TBI including the problems of talkativeness, tangentiality, and fragmented thought processes. In the 1990s, the term cognitive-communication disorder emerged (Hartley, 1995) in recognition of the relationship between impaired cognition and its wider ramifications for everyday communication skills. The debate regarding the definition of “cognitive-linguistic” disorders continues with the proposition that the term lacks terminological clarity, which undermines the assessment of complex communication functioning (Body & Perkins, 2006). Nonetheless, it is now widely accepted that the communication difficulties following TBI are mostly the result of a combination of cognitive and linguistic impairments. In addition, it is also recognized that executive functioning impairments in the domains of attention, memory, organization, planning, flexible problem solving, and self awareness are consistently seen in people after TBI (Anderson, Bigler, & Blatter, 1995; Levin, Goldstein, Williams, & Eisenberg, 1991). These types of difficulties can have a significant deleterious impact on a person’s day-to-day interactions leading to social communication impairments. Elements of discourse pragmatics, such as turn-taking and social judgment, and theory of mind elements (e.g., appreciation of another’s perspective) may also be impaired due to executive dysfunction (McDonald & Pearce, 1998). Many studies have shown that individuals with TBI experience difficulties during conversation. Poor conversational competence in individuals with TBI is the result of verbosity, inappropriate responses to social communication, poor topic maintenance, and reliance on additional conversational prompting provided by their communication partners (C. A. Coelho, Youse, & Le, 2002; Godfrey & Shum, 2000; Togher, Hand, & Code, 1997). It is thus not surprising that conversations with individuals with TBI have been described as less enjoyable, less interesting, and less rewarding (Bond & Godfrey, 1997; C. A. Coelho et al., 2002). This is problematic for individuals with TBI as conversation is fundamental for socializing and strengthening interpersonal relationships (C. A. Coelho et al., 2002). The assessment of executive functioning as it pertains to communication will be described in further detail in the next section. A common aspect of all tests of executive function is that the patient is placed in a situation that requires them to respond to novel or non-routine demands with increasing levels of task complexity (Shallice, 1988). Assessments of executive functioning that includes an emphasis on communication functioning frequently rely on decontextualized tasks that use pen and paper, visual tasks, and objects. Unfortunately, the inherent structure of these assessments can enhance the performance of a person with frontal lobe impairment leading to failed diagnosis of executive functioning difficulties (Eslinger & Damasio, 1985). For example, usually testing is conducted in a quiet office, without distractions and with a clinician who coordinates the test administration, provides direction regarding rules, sets goals, and prompts the person when to start and when to stop the task. The core deficits inherent in executive functioning, namely establishing a functional framework to complete the operation, starting, stopping, tracking and switching, may be circumvented by the controlled nature of the assessment task (Manchester, Priestley, & Jackson, 2004). To guide practitioners regarding the best executive functioning tests to use in clinical practice, members of the Academy of Neurologic Communication Disorders and Sciences (ANCDS) Practice Guidelines Group (Turkstra, Coehlo, & Ylvisaker, 2005) published a list of the standardized norm-referenced tests that met established validity and reliability criteria for the TBI population. There were seven tests suggested (Box 15-1). As there is currently limited evidence with regard to standardized instruments for individuals for cognitive-communication disorders, the committee limited its recommendations to practice options. The recommendations were to use caution when evaluating people with brain injury using existing standardized tests; to consider standardized testing within a broader framework that incorporated factors such as the person’s pre-injury characteristics, stage of recovery, and everyday communication demands; and to collaborate with other health professionals, particularly when considering the use of impairment-level cognitive tests (L. Turkstra, Ylvisaker, Coelho, et al., 2005). Additionally, there are a plethora of executive functioning tests that do not specifically invoke language processing and therefore will not be discussed in this chapter (e.g., Rey-Osterrieth Complex Figure, Tower of London, Raven’s Colored Progressive Matrices, and Wisconsin Card Sort Test). For a review of these assessments, the reader is referred to Keil & Kaszniak (2002). Rather, the focus of the assessments described here will be the evaluation of executive functioning that is associated with communication skills in everyday contexts, including standardized and non-standardized approaches, which are discussed in the next section. Executive functioning affects all aspects of our everyday activity (Ylvisaker & Feeney, 1998) and so evaluation tools have begun to emerge to capture these difficulties (Kilov, Togher, & Grant, 2009). The question of when to complete these assessments remains unanswered, although it was recently reported that executive functioning tests were more predictive of recovery if administered 5 months post-injury than at 8 weeks post-injury (Green, Colella, Hebert, et al., 2008). However, there is also evidence that executive functioning can be screened in the acute setting (Bennett, Ong, & Ponsford, 2005) using the Dysexecutive Questionnaire (DEX), which is a subtest of the Behavioral Assessment of the Dysexecutive Syndrome (BADS) (Wilson, Alderman, Burgess, et al., 1996). This battery includes a 20-item Dysexecutive Questionnaire (DEX) that samples the range of problems in four broad areas of likely change: emotional or personality changes, motivational changes, behavioral changes, and cognitive changes. The questionnaire has two versions, one of which is completed by the client (the DEX) and one of which is completed by a significant other who has close, preferably daily contact with the client (DEX-R). Bennett et al. (2005) found that while neuropsychologists and occupational therapists’ ratings on the DEX were strongly associated with measures of executive functioning, the ratings of family members and people with TBI were not. This finding suggested that clinicians need to be judicious regarding when the DEX is administered and who completes it. In general, the assessments described in this chapter are best administered in the sub-acute and chronic phases of recovery after an acquired brain injury. One reason for this is that difficulties often do not become evident until the person returns to his/her everyday situations, such as shopping, working, and conversing in group situations. It is also true that the severity and degree to which executive impairment manifests from one individual to the next varies enormously, influenced not only by the severity of the injury but also pre-morbid intelligence, motivation, and the nature of the task (Shallice & Burgess, 1991). In less severe cases, routine behavior previously learned may be carried out normally and basic skills retained. However, there may be a disruption of the capacity to focus attention voluntarily and to deal with novel situations adaptively. When deficits are more pervasive all behavior may be disrupted. As the relationship between communication and executive functioning is clearly multifaceted, a variety of theoretical approaches have been taken to their evaluation. The complex nature of the area has also led to the development of multidisciplinary approaches to evaluation with considerable overlap between speech language pathology and neuropsychology. The resulting assessments developed over the past decade are innovative, reflective of everyday contexts, and encompass the latest technological advances, including: (1) the use of virtual reality (e.g., the Virtual Multiple Errands Test or VMET) (Rand, Rukan, Weiss, & Katz, 2009), (2) a focus on the intricacies of social interactions (the Awareness of Social Inference Test) (McDonald, Flanagan, & Rollins, 2002), and (3) an examination of the subtle cognitive-communication deficits arising from acquired brain injury called the Functional Assessment of Verbal Reasoning and Executive Strategies (FAVRES) (MacDonald, 1998). This test is based on the Multiple Errands Test (MET) (Alderman, Burgess, Knight, & Henman, 2003; Burgess, Alderman, Forbes, et al., 2006; Knight, Alderman, & Burgess, 2002), which is performed at a real shopping mall or in a hospital environment and involves the completion of various tasks, rules to adhere to, and a specified time frame. For example, in the MET the individual is asked to buy six items, such as: • Buy a bottle of mineral water • Get a napkin from the coffee shop • Pick up an envelope that is waiting for you at the FOX shop and do what is necessary • Get a visiting card from one of the shops The individual is then given a set of rules to abide by, including, for example, “You are not allowed to go into the same shop more than once, and you are not allowed to buy more than two items at any shop.” Finally, the individual is asked to meet the tester at a certain time at a preset location. The tester follows the participant around the shopping mall recording mistakes, with scoring relating to behaviors such as non-efficiency, rule breaking, and use of partial and complete mistakes in completing a task. The MET was moderately correlated with most of the items in the DEX (Alderman et al., 2003) demonstrating ecological validity. Two problems with the MET are the time consuming nature of completing this assessment and the requirement that the individual is independently ambulant. Rand and colleagues (Rand, Katz, & Weiss, 2007) therefore used virtual reality technology to create a virtual mall. The Virtual Mall (VMall) is a functional virtual environment consisting of a large supermarket where individuals with acquired brain injury can engage in the complex task of shopping (Rand et al., 2007). The VMET is a virtual reality evaluation of the person engaged in an adapted version of the MET. While the VMET had moderate to high correlations with the MET in post-stroke participants and older healthy controls (Rand et al., 2009), further psychometric evaluation is needed. The types of mistakes made by the post-stroke participants were similar in both the real mall and the VMall, including problems with planning, difficulty with multitasking, and a lack of awareness of mistakes. This assessment offers a promising window into the future of evaluating executive functioning deficits. As virtual reality technology continues to improve, it may be possible to expand the communicative contexts the individual with acquired brain injury is asked to participate within while remaining in the clinic room. A limitation, however, is that in the current VMall there are no communicative interactions that mirror real-life interaction—the virtual reality platform merely offers the clinician an insight into the organization and planning of shopping, and the individual’s response to distracters such as background music and announcements. Executive functioning impairments have implications for the assessment of social communication skills. Social communication encompasses a complex array of components including, for example, the ability to make inferences, and to understand and make requests (McDonald, 1992, 1993; McDonald & Pearce, 1996, 1998; Pearce, McDonald, & Coltheart, 1998; L. S. Turkstra, McDonald, & Kaufman, 1995). This research has shown that a proportion of adults with TBI misinterpret conversational inferences generated by discrete speech acts. Given that linguistic performance is relatively normal in these people, it is thought that they have difficulty utilizing the contextual information necessary to generate these inferences. However, the nature of the contextual cues involved and whether any particular sources of contextual cues are more poorly processed is not well understood (McDonald, 2000). Executive abilities related to concept formation and inhibition have been implicated in the capacity to interpret non-literal language (Martin & McDonald, 2006). Studying the effect of how indirect contextual information is detected by conversational speakers has led to advances in the study of sarcasm (McDonald, 2007; McDonald & Pearce, 1996), use of hints (McDonald & Sommers, 1993), and, more recently, theory of mind investigations with people with TBI (Bibby & McDonald, 2005; Martin & McDonald, 2005). It is thought that the ability to detect sarcasm is impaired in those with frontal injury because the frontal lobes control the executive processes that enable us to respond adaptively to novel stimuli by overriding routine, habit-driven responses. It is thought that damage to these processes may lead to more automatic responses, which are either stimulus-bound or habit driven. This leads to a reduced appreciation of inferential meanings in language because they are stimulus-bound to the most concrete aspects of the information given and are not able to suppress their tendency to respond in a routine way to such attributes. They are therefore unable to appreciate alternative meanings or associations (McDonald & Pearce, 1996). In McDonald and Pearce’s (1996) study of 10 people with TBI it was determined that this group could interpret consistent verbal exchanges but had difficulty with literally contradictory (sarcastic) verbal exchanges. They found that the literal meaning of a sarcastic comment needed to be rejected in order for the inference to be detected. Theory of mind concerns the ability to make judgments about the mental states of others. It is thought that this skill underpins the ability to interpret and predict how others will behave. The traditional approach to evaluating this skill is through the use of “false belief” and complex story tasks that examine how participants use conceptual or pictorial information about the beliefs of those depicted in the story. While this has been a tantalizing line of inquiry in the study of the unique frontal deficits that are associated with TBI, it seems that theory of mind is not a singular ability, and that the judgments made in these traditional story tasks could involve non–theory of mind inferential reasoning (Bibby & McDonald, 2005) and cognitive flexibility (Henry, Phillips, Crawford, et al., 2006). Nonetheless, people with severe TBI demonstrate specific impairments on tasks requiring them to make inferences about others’ mental states when compared to control participants (Bibby & McDonald, 2005). In response to these findings, McDonald and colleagues developed the Awareness of Social Inference Test (TASIT) (McDonald et al., 2002) which is an audiovisual clinical tool for the assessment of social perception. There are 3 parts: Part 1 assesses emotion recognition, Parts 2 and 3 assess the ability to interpret conversational remarks meant literally (i.e., sincere remarks and lies) or non-literally (i.e., sarcasm) as well as the ability to make judgments about the thoughts, intentions, and feelings of speakers. The subtests relating to executive functioning, namely Parts 2 and 3, comprise video vignettes where the participants watch brief dialogues between two actors. In Part 2 (Social Inference—Minimal), there are 15 vignettes; 5 where the exchange is sincerely meant, 5 where similar scripts were enacted sarcastically, and 5 where the scripts are literally paradoxical (i.e., they could only make sense if it was understood that one person was being sarcastic). After viewing each vignette, participants are required to answer questions regarding the speaker’s (1) feelings, (2) beliefs, (3) intentions, and (4) meaning. In Part 3 of the TASIT (Social Inference—Enriched), there are 16 vignettes that provide additional information before or after the dialogue of interest to “set the scene.” For example, two co-workers confide to each other that a party over the weekend was truly dreadful. This is followed by a scene with the host of the party in which he/she claims the party was a great success. In half the vignettes the scripts are enacted as a diplomatic lie, trying to make the best of a bad situation. In the remainder they are enacted sarcastically. As with Part 2, the ability to interpret vignettes is assessed via a set of 4 questions for each vignette. The TASIT is an important advance in the assessment of social communication functioning. It is sensitive to disorders such as TBI (McDonald, Tate, Togher, et al., 2008), schizophrenia (Rankin, Salazar, Gorno-Tempini, et al., 2009), and the behavioral form of frontotemporal dementia (bvFTD) and Alzheimer’s disease (Kipps, Nestor, Acosta-Cabronero, et al., 2009). The TASIT has adequate psychometric properties with demonstrated reliability and validity (McDonald, Bornhofer, Shum, et al., 2006) and is available in alternate forms. The Functional Assessment of Verbal Reasoning and Executive Strategies (FAVRES) is an assessment tool designed specifically for the acquired brain injury population (MacDonald & Johnson, 2005). It is a reliable and discriminating measure for differentiating performances of those with and without ABI (MacDonald & Johnson, 2005). Importantly, it provides an evaluation of executive functions within everyday communication contexts. There are four functional tasks that simulate everyday life including: planning an event, scheduling a workday, making a decision, and building a case to solve a problem. While not designed specifically to comprehensively assess executive functions, the tasks in this assessment elicit aspects of executive functioning in simulated real-life contexts. For example, the Planning an Event subtest involves choosing a social event given certain restrictions, while the Scheduling subtest involves sequencing, organizing, and prioritizing important daily events with time constraints. The latter of these tasks was found to be the most powerful discriminator of whether participants with TBI returned to work (Isaki & Turkstra, 2000). All the tests described in this chapter have been standardized evaluations of some aspect of executive functioning and communication performance. We use executive functions every day in our interactions with others, however, and so ideally it would be beneficial to evaluate the effects of executive functioning deficits in these contexts. While there is a paucity of research in this area, there have been some attempts to provide frameworks for clinicians to examine executive functioning in real-life communication contexts. Two of these are to be discussed here. These include the concept of “collaborative contextualized hypothesis testing” proposed by Ylvisaker and colleagues (Ylvisaker & Feeney, 1998), and the General Behavioral Observation Form (Hartley, 1995). This rather daunting title merely reflects the process of working out reasons for a person’s difficulty in everyday social contexts. So, for example, if a person is having difficulty reading a chapter and answering questions about the content, there are a number of possible reasons this could be occurring, including problems with executive functioning (Table 15-1). Table 15-1 Some Hypotheses About Why a Person Has Difficulty with a Reading Comprehension Task From Coelho, C., Ylvisaker, M., & Turkstra, L. S. (2005). Nonstandardized assessment approaches for individuals with traumatic brain injuries. Seminars in Speech & Language (4), 223–241. These are only some of the possible reasons a person may be having difficulty. Others include problems with visual acuity, memory, speed of information processing, language difficulties, and behavioral problems. Ylvisaker & Feeney (1998) suggest that the process of hypothesis testing is a dynamic one that should be conducted in collaboration with all members of the professional team, including family members. They suggest that this process is best conducted in real contexts in the individual’s life. As people with TBI often perform well on standardized, structured tests, but fail in their everyday activities, Ylvisaker suggests they be evaluated in the situations where they are having difficulty. It is also suggested that this process is ongoing as consequences of a brain injury may not emerge for months or even years after the injury. Examining communication in daily contexts is a challenge. One solution to simplify observing specific behaviors is the use of checklists. One such tool, called the General Behavioral Observation Form, was developed by Hartley (1995) as a way for raters to characterize an individual’s cognitive functions, including attention, executive functions/meta-cognition, processing and response speed, emotional control, drive, motivation, and memory. The rater judges where the function is “within normal limits,” “not able to judge,” or is an “area of need.” Under the heading “Executive Functioning” the following areas can be rated on this form: • Awareness of deficits/errors • Spontaneous use of strategies • Awareness of strategies used • Ability to accept/use feedback • Flexibility in shifting tasks In Coelho et al.’s (2005) review of evidence on the use of non-standardized procedures for the assessment of people with TBI, it is recommended that collaborative contextualized hypothesis testing should be used for planning behavioral interventions and to provide supports for the person with TBI. The use of checklists is suggested to have face and content validity but requires ongoing investigation (Table 15-2). Table 15-2 Summary of Executive Functioning Assessments
Clinical approaches to communication impairments due to executive dysfunction
How does impaired executive functioning affect communication?
Assessments of executive functioning
Standardized tests of executive functioning that incorporate communication
Tests of executive functioning and communication in everyday contexts: standardized tests
The virtual multiple errands test
The awareness of social inference test (TASIT)
The functional assessment of verbal reasoning and executive strategies (FAVRES)
Non-standardized approaches to assessing communication and executive functioning
Collaborative contextualized hypothesis testing
Executive Function
Description of Underlying Problem
Attention
Inadequate sustained attention, distractibility/weak filtering, inability to divide attention, difficulty shifting from the previous task
Orientation
Unclear orientation to the task
Working memory
Insufficient space in working memory to hold the task instructions, reading strategies, and information from the paragraph
Self-monitoring
Failure to recognize that the task is difficult and requires special strategic effort
Organization/integration
Difficulty organizing information to comprehend the text, to understand how details relate to each other, to understand how the questions relate to the text, or to formulate an organized answer
General behavioral observation form
