Treatment of Characteristics of Right Hemisphere Disorder (RHD)

Right hemisphere disorder (RHD) occurs when there is damage to the right cerebral hemisphere of the brain. This can take place due to a stroke, traumatic brain injury, surgery, tumor, an infection or illness (Blake, Fryman, & Venedictor, 2013). The right hemisphere of the brain is responsible for attention, memory, reasoning and problem solving, semantics and pragmatics and speech prosody (Halper & Goldfarb, 2013). When damage to the right hemisphere occurs, it can impact an individual’s cognition, and/or communication. According to Halper & Goldfarb (2013), cognitive deficits seen in RHD include neglect, constructional impairment, limb apraxia, anosognosia or prosopagnosia, and confabulation. Communication deficits in RHD can impact an individual’s speech and/or language.

Both formal and informal tests can be used to diagnose RHD.  Informal tests can be used to assess neglect, prosody, pragmatics, and language deficits. Formal tests can assess cognitive and communication deficits such as the Discourse Comprehension Test, Evaluation of Communication Problems in RHD, Rapid Assessment of Problem Solving and many more (Halper & Goldfarb, 2013).

There are many characteristics displayed by RHD that impact communication, emotion, facial recognition, visuoperceptual and constructional impairment, and the most common, perceptual impairment. This research paper will discuss perceptual, constructional and communication impairments and current treatment practices for each.

When working with individuals who have RHD there are three approaches that speech language pathologists can take for treatment. First, the level of impairment approach focuses on areas of relative strength and weakness in a patient’s performance. Second, the fundamental abilities approach targets processes that are expected to underlie a range of deficiencies and to be necessary for eventual communication success such as attention. Third, the functional abilities approach focuses on daily life competencies and concerns. When treating patients with RHD they may be indifferent and in denial, passive in therapy, and their homework may be neglected. Treatment needs to be deferred until denial resolves and then it should be highly structured, have clear goals, provide feedback about errors and inappropriate responses and improve self-monitoring skills in the patient.

 The number one characteristic seen with RHD is perceptual impairment, which includes denial of illness and left hemispatial neglect. Denial of the illness, also known as anosognosia causes an individual to disregard, underestimate the severity, or deny that a disability has occurred. Due to the denial of impairment, individuals may be disinterested in therapy. The research regarding treatment of anosognosia is lacking, however Blake, Novak, and Freer (2016), have provided suggestions such as discussing the problem and providing verbal and visual feedback to bring awareness of errors to the individual. Having an individual watch a video of their own performance can help develop awareness of errors. If the individual sees themselves using cues and being successful in a video, the individual may become aware and understand that neglect is occurring on the left side. Ideally, in the next step the individual would be able to internalize the strategies and use them more spontaneously. If a breakthrough does not occur, teach the individual to use a strategy habitually, even if they feel it is not necessary.  However, the researchers explain that the habituation takes many hours of treatment, and patience from both the patient and the clinician.

Left hemispatial neglect is the most common feature associated with perceptual impairment. According to Hattori et al. (2018), neglect is an “impaired state of spatial attention, or the inability to pay attention to the left space.” The biggest issue when treating neglect is anosognosia, because the patient has reduced awareness of deficits. Researchers Spaccavento, Cellamare, Cafforio, Loverre, and Craca (2016), list visual scanning training, limb activation, mental imagery, sustained attention training, prism adaptation, noninvasive brain stimulation, vestibular and optokinetic stimulation, and pharmacological therapy as rehabilitation treatments for neglect. These researchers conducted a study that looked specifically at prism adaption, and the more popular approach, visual scanning treatment.

Visual scanning treatments have a top-down approach, that are based on voluntary shifting of attention to the neglected side. The goal of this treatment is to “improve visual-scanning behavior, requiring the patient to actively and consciously pay attention to stimuli on the contralateral side” (Spaccavento et al., 2016). In administering this treatment, researchers set the client about 3 feet in front of a large screen where the stimuli would be appearing. The stimuli were digits 1-9, or symbols, and were positioned in 1 of 48 positions. The individual was asked to name the stimulus that was presented, and quickly press a button after. This process began with stimuli being presented on the right and slowly shift left, and then gradually stimuli appeared 2 or 3 horizontal positions to the left of each previous stimulus. Lastly, sequences were presented randomly at the end of the treatment. Depending on the difficulty, the order of presentation, encouragement from the therapist, or possibly a warning signal prior to the stimulus changed. Additional scanning tasks that Spaccavento et al. (2016) had patients complete were reading and copying training, copying of line drawings, and description of scenes.

Spaccavento et al. (2016), are not the only researchers who see visual scanning treatments as a primary option in treating neglect. Sutton (2018), states that visual scanning tasks are the most effective treatments for left neglect, as it can provide quick results, especially if the task is similar to the desired outcome, gives feedback, and is delivered intensively. Additionally, Blake, Novak, and Freer (2016), describe a visuospatial motor treatment, which is a form of treatment that incorporates visual scanning and then adds in spatial and motor components. The researchers explain how movement of the left side of the body is useful because it creates activity within the right hemisphere, which may increase activity in the attentional circuits of the brain, increasing attention to the left. These researchers describe it as the lighthouse strategy, which incorporates imagery of how a lighthouse functions with the scanning and movement components. This strategy encourages the patient to use a full head motion from the left to the right, scanning just like a lighthouse would do. The lighthouse strategy has shown evidence that it helps with neglect, and aids in environment navigation because it has the patient scanning their environment fully from left to right, which could help them to avoid bumping into doorways.  More research is needed to better look at generalization and maintenance of the improvements made in therapy, as well as to tease apart the various subtypes of neglect rather than treating it as a single disorder.” CITE

Prism adaptation is a bottom-up technique that is aimed at enhancing automatic orientation toward the left space (Spaccavento et al., 2016). Researchers explain that this task consisted of repetition of exercises where the patient pointed to targets placed in front of them, while wearing prismatic lenses. “The prismatic glasses induce a visual field deviation toward the right, which patients with neglect correct by shifting toward the controlesional side of space to compensate for the prism-induced error. This left compensatory shift can also be observed after the removal of the prism lenses (after effect)” (Spaccavento et al., 2016). The research done by Spaccavento et al. (2016), gave evidence that visual scanning and prism adaptation treatments do in fact improve patient’s neglects signs, especially in personal and peri-personal spaces.

Constructional impairment, also known as constructional apraxia, is a visuospatial perceptual and organizational impairment, rather than a motor planning impairment that is typically see in apraxia according to Brookshire (2014). Russell et al. (2010), explains that individuals with RHD do not have trouble making relevant individual movements, but struggle to accurately copy simple drawings. Adults with RHD respond quickly and impulsively. They make errors often and attempt to correct them by adding more line to their drawings or by aimlessly rearranging designs (Brookshire & McNeil, 2014).  Details on the left side of a page will often be omitted and the drawings become fragmented, distorted, or crowded towards the right side of the page (Brookshire, 2014). Halper and Goldfarb (2013), explain that the struggle in drawing geometric designs/ drawing or manipulating 3-D objects are due to the deficits in attention, perception and neglect.

There are numerous ways to test for constructional impairments, one of which being the Montreal Cognitive Assessment, because it has visuo-perceptual aspects within the test.  When providing treatment for constructional impairment, it is important to work on the patient’s attention. There are computer-based attention drills, maze solving, letter cancelation, or paper and pencil tasks. Halper and Goldfarb (2013), give examples such as having the patient draw lines between points, lines through other lines, connecting dots to make letters or shapes, and copying or making their own simple drawings.

Individuals with RHD can have communication impairments as well, with deficits in speech and/or language. According to Halper and Goldfarb (2013), language deficits associated with RHD include trouble with inferencing, abstract and concrete words, understanding narrative discourse, and pragmatic skills. Researchers identified prosody, using and understanding emotional speech, and linguistic factors as the areas of speech that can be affected by RHD. According to Brookshire and McNeil (2014), many adults with RHD have communication impairments that make it difficult to “communicate emotion, express themselves coherently and efficiently, comprehend humor, sarcasm, and nonliteral material, and behave appropriately in conversations.” One of the most common communication impairments of adults with RHD is their excessive, distorted, and at times inappropriate connected speech (Brookshire & McNeil, 2014). Comprehension is also impacted, so they may have trouble with implied meaning, can’t get past literal meanings, contribute distorted reasons for their truth, can’t determine moral of a story, etc.

Researchers Blake et al. (2013), noted that until more treatment studies are completed, rehabilitation services will be from experts in the field using theoretically based treatments, and treatments that are designed for other neurological populations that have similar deficits to those linked with RHD. The theoretically based treatment that is recommended by Blake et al. (2013) incorporates major emphasis on contextual cues. Researchers recommend using contextual cues in treatment to “(a) determine appropriate meanings of ambiguous words and sentences; (b) activate and access distant meanings or features of words that are contextually important; (c) determine meanings of nonliteral language such as idioms and metaphors; and (d) determine speakers’ intents, such as interpreting sarcasm, white lies, and meanings conveyed through prosody.” This theoretical treatment approach is supported by Tompkins, Scharp, Meigh, Blake, and Wambaugh (2012), and their research regarding deficits in coarse coding and suppression and RHD adults’ ability to use strong contextual cues to determine meaning. Research has also found that the use of structured feedback, videotaped interactions, modeling, rehearsal, and training of self-monitoring are treatment strategies for individuals with a traumatic brain injury that could also work for adults with RHD (Blake et al., 2013).

 Right hemisphere disorder only began being treated a short twenty years ago, which means evidence-based research for treatment approaches for the copious characteristics is lacking. The lack of research adds to the challenge for speech language pathologists as patients with RHD appear on the caseload. Like Blake et al. (2013) noted, until more research is done, SLP’s will have to continue using theoretical approaches, and treatments that were originally designed for other neurological disorders. However, despite the lack of research for concrete treatment approaches, SLP’s have been serving the RHD population with what information they do know and watching the patients carefully to see if it is successful. Data from ASHA’s National Outcomes Measurement System (NOMS), proves that success. This data shows that patients with RHD who have received therapy from SLP’s show improvement in problem solving by 73%, improvement in memory by 74%, improved pragmatics by 77%, and increased attention by 80% (Barrera, 2018). This data shows that SLP’s are on the right track, and over time more research will continue to be completed in order to serve the RHD population even more so. The goal of treatment for RHD is to inform the patient and their families of the nature of the disorder, provide appropriate treatment to the deficits that are being displayed, and encourage the patient and their families to continue treatment strategies after therapy is over.

References

• Blake, M. L., Frymark, T., & Venedictov, R. (2013). An evidence-based systematic review on communication treatments for individuals with right hemisphere brain damage. American Journal of Speech-Language Pathology, 22(1), 146–160. https://doi-org.ezproxylocal.library.nova.edu/10.1044/1058-0360(2012/12-0021)
• Brookshire, R. H., & McNeil, M. R. (2014). Introduction to neurogenic communication disorders (8th ed.). St. Louis, MO: Mosby.
• Hattori, T., Ito, K., Nakazawa, C., Numasawa, Y., Watanabe, M., Aoki, S., … Yokota, T. (2018). Structural connectivity in spatial attention network: reconstruction from left hemispatial neglect. Brain Imaging & Behavior, 12(2), 309–323. https://doi-org.ezproxylocal.library.nova.edu/10.1007/s11682-017-9698-7
• Tompkins, C. A. (1995). Right hemisphere communication disorders: Theory and management. San Diego, CA: Singular Publishing Group, Inc.
• Blake, M., Novak, K., & Freer, J. (2016). Treatment strategies for unilateral visuospatial neglect and anosognosia. Retrieved October 23, 2018, from https://www.medbridgeeducation.com/blog/2016/02/treatment-strategies-for-unilateral-neglect-and-anosognosia/
• Russell C, Deidda C, Malhotra P, Crinion JT, Merola S, Husain M, … Husain, M. (2010). A deficit of spatial remapping in constructional apraxia after right-hemisphere stroke. Brain: A Journal of Neurology, 133(4), 1239–1251. https://doi-org.ezproxylocal.library.nova.edu/10.1093/brain/awq052
• Sutton, M. (2018). Left neglect after stroke – Definition & treatment exercises. Retrieved October 24, 2018, from https://tactustherapy.com/what-is-left-neglect/
• Tompkins, C., Scharp, V., Meigh, K., Lehman Blake, M., & Wambaugh, J. (2012) Generalization of a novel, implicit treatment for coarse coding deficit in right hemisphere brain damage: A single subject experiment. doi:
  http://dx.doi.org.ezproxylocal.library.nova.edu/10.1080/02687038.2012.676869 
• Halper, H., & Goldfarb, R. (2013). Language and motor speech disorders in adults. Burlington, MA: Jones & Bartlett Learning
• Spaccavento, S., Cellamare, F., Cafforio, E., Loverre, A., & Craca, A. (2016). Efficacy of visual-scanning training and prism adaptation for neglect rehabilitation. Applied Neuropsychology: Adult, 23(5), 313–321. https://doi-org.ezproxylocal.library.nova.edu/10.1080/23279095.2015.1038386
• Barerra, M. (2018). Right hemisphere syndrome [PowerPoint slides]. Retrieved from https://nsu.instructure.com/courses/2359486/files/131460583?module_item_id=40088482