Susan A. Leon

A pilot study of use-dependent learning in the context of Constraint Induced Language Therapy

This investigation reports the results of a pilot study concerning the application of principles of use-dependent learning developed in the motor rehabilitation literature as Constraint Induced Therapy to language rehabilitation in a group of individuals with chronic aphasia. We compared treatment that required forced use of the language modality, Constraint Induced Language Therapy, (CILT) to treatment allowing all modes of communication. Both treatments were administrated intensively in a massed practice paradigm, using the same therapeutic stimuli and tasks. Results suggest that whereas both interventions yielded positive outcomes, CILT participants showed more consistent improvement on standard aphasia measures and clinician judgments of narrative discourse. These findings suggest that CILT intervention may be a viable approach to aphasia rehabilitation.

Treatment of naming in nonfluent aphasia through manipulation of intention and attention: A phase 1 comparison of two novel treatments

Twenty-three chronic nonfluent aphasia patients with moderate or severe word-finding impairments and 11 with profound word-finding impairments received two novel picture-naming treatments. The intention treatment initiated picture-naming trials with a complex left-hand movement and was designed to enhance right frontal participation during word retrieval. The attention treatment required patients to view visual stimuli for picture-naming trials in their left hemispace and was designed to enhance right posterior perisylvian participation during word retrieval. Because the intention treatment addressed action mechanisms and nonfluent aphasia reflects difficulty initiating or maintaining action (i.e., language output), it was hypothesized that intention component of the treatment would enhance re-acquisition of picture naming more than the attention component. Patients with moderate and severe word-finding impairment showed gains with both treatments but greater incremental improvement from one treatment phase to the next with the intention than the attention treatment. Thus, the hypothesis that intention component would be a more active constituent than the attention component was confirmed for these patients. Patients with profound word-finding impairment showed some improvement with both treatments but no differential effects for the intention treatment. Almost all patients who showed treatment gains on either treatment also demonstrated generalization from trained to untrained items.

Affective Aprosodia from a Medial Frontal Stroke.

BACKGROUND AND OBJECTIVES Whereas injury to the left hemisphere induces aphasia, injury to the right hemispheres perisylvian region induces an impairment of emotional speech prosody (affective aprosodia). Left-sided medial frontal lesions are associated with reduced verbal fluency with relatively intact comprehension and repetition (transcortical motor aphasia), but persistent affective prosodic defects associated with right medial frontal lesions have not been described. METHODS We assessed the prosody of a man who sustained a right medial frontal cerebral infarction seven years prior. RESULTS While propositional speech expression was normal including syntactic prosody, the patient was impaired at expressing emotions using prosody. His comprehension and repetition of prosody were also impaired but less so than expression. CONCLUSIONS Right medial frontal lesions can induce an affective aprosodia that primarily impairs expression.

Errorless practice as a possible adjuvant to donepezil in Alzheimer's disease.

Six individuals with probable Alzheimers disease (AD) participated in a phase 1 study employing a repeated measures, parallel baseline design testing the hypothesis that error-free experience during word production practice combined with an acetyl cholinesterase inhibitor would improve confrontation naming ability. While acetyl cholinesterase inhibitors are safe and delay cognition decline associated with AD, improvement over baseline cognition is less evident; clinically significant cognitive deficits persist and progress. Both animal and clinical research strongly implicate acetylcholine in learning, a form of neuroplasticity. In clinical practice, however, people with AD are given cholinergic medications without concomitant systematic/targeted retraining. In this study six participants with probable AD and taking donepezil participated in targeted word production practice using an errorless learning strategy. Results showed that combining behavioral enrichment training and an acetyl cholinesterase inhibitor resulted in significant improvements in verbal confrontation naming of trained items for three of six participants. Differences in baseline dementia severity, living conditions, and medications may have influenced the training response. Detection of substantial treatment effects in 50% of subjects suggests further language treatment studies in AD in combination with an acetyl cholinesterase inhibitor are warranted and provide useful information on inclusion/exclusion criteria for use in subsequent studies.

Novel treatments for expressive aprosodia: A phase I investigation of cognitive linguistic and imitative interventions

This study investigated two mechanism-based treatments for expressive aprosodia, a disturbance in emotional prosody thought to be governed by the right hemisphere. The 3 participants all suffered right CVAs resulting in expressive aprosodia. Presence of expressive aprosodia was determined by performance on two batteries of emotional communication. A single subject ABAC design was employed in which two treatments, one imitative and one cognitive linguistic, were assigned in random order. All participants in this study were randomly assigned to begin with the cognitive linguistic treatment. Probes of treated and untreated emotions were completed during baseline and therapy phases. Probe items were judged by a reliable, trained rater blind to time of testing. Visual and statistical analyses were completed. These analyses confirmed that both treatments were active. For example, effect size calculations confirmed modest to substantial treatment effects for both treatments in all 3 patients. Replication to increase confidence about treatment effect and enhance understanding of the neuromechanisms underlying aprosodia is underway.

Changes in aphasic discourse after contrasting treatments for anomia

Background: Discourse analysis is a key element in determining treatment effects. However, it is extremely labour intensive, requiring in‐depth knowledge of linguistics and aphasiology; thus, it is often neglected in the analysis of treatment outcomes. A clinically practical method of discourse analysis would be beneficial for evaluation and determination of treatment efficacy. Aims: The current study investigates changes in discourse content following contrasting treatments for anomia using grammatical analysis. In addition, we pilot the use of a new information measure. Methods & Procedures: We compare discourse changes after a gestural + verbaltreatment and a semantic‐phonologic treatment for nouns and verbs on two groups of individuals with aphasia. Analyses compared discourse samples from 14 participants taken at baseline, post‐phase 1, and post‐phase 2. In addition to traditional measures such as number of nouns, verbs, and sentence types, a new measure of information is introduced, the Utterance with New Information (UNI). The UNI is designed to assess content in non‐propositional, impaired speech in open‐ended discourse. Outcomes & Results: Noun production increased in participants of both treatments, whereas grammatical sentences increased only in participants of the semantic‐phonologic treatment. Production of UNIs increased in participants of both treatments as well as over time. Conclusions: This study demonstrates that a few easily counted measures of discourse production can provide clinically useful information for the clinician. Moreover, these findings suggest discourse analysis is a viable method of determining treatment outcomes especially given that improving discourse is the ultimate goal of all aphasia treatments.

Effects of two treatments for aprosodia secondary to acquired brain injury

Expressive aprosodia is an impaired ability to change ones voice to express common emotions such as joy, anger, and sadness. Individuals with aprosodia speak in a flat, unemotional voice that often results in miscommunicated emotional messages. This study investigated two conceptually based treatments for expressive aprosodia: imitative treatment and cognitive-linguistic treatment. Five women and nine men with expressive aprosodia following right-hemisphere brain damage received the treatments in two phases 1 month apart in random order. Treatment was received 3 to 4 days a week for a total of 20 sessions each phase. As the outcome measure, sentences that elicited treated (happy, angry, sad, neutral) and untreated (fear) emotional tones of voice were administered during baseline, prior to treatment sessions, following treatment termination, and at 1- and 3-month follow-ups. Effect sizes indicated that treatment effects were modest to substantial and that 12 participants responded to at least one treatment. Four responsive participants who were available for follow-up showed benefit at 1 and 3 months posttreatment. Most visual and statistical analyses were congruent.

Divergent Task Performance in Older Adults: Declarative Memory or Creative Potential?

Divergent thinking is a process or method used to generate creative ideas by exploring many possible solutions or responses, and is a critical element of creativity. Lesion and imaging studies have shown that the frontal lobes are important in mediating divergent thinking, and frontal lobe function is highly dependent on white matter connections with subcortical and cortical networks. Normal aging often results in deficits in functions controlled by the frontal lobes, as well as decrements in white-matter connectivity. Objectives of this study included comparing non-time-constrained tasks of verbal divergent processing in young adults (YAs) and older adults (OAs) and correlating performance with tasks of working memory, language ability, and disengagement/inhibition. Participants were 30 YAs and 30 OAs. Contrary to the a priori hypothesis, OAs produced significantly more unique responses than YAs, although total fluency was not significantly different. Correlational analyses examining the groups together and separately revealed a number of differences suggesting that the groups were utilizing different underlying cognitive abilities to complete these tasks. Future studies are needed to test the hypothesis that the primary factor resulting in higher uniqueness scores for the OAs was a greater wealth of experiences, including in the use of language.

Cognitive–motor dysfunction after severe traumatic brain injury: A cerebral interhemispheric disconnection syndrome

Background/Objectives: In most right-handed people, the left hemisphere is dominant for programming the temporal and spatial “how” (praxis) aspects of purposeful skilled movements, and the right hemisphere is dominant for control of the intentional “when” aspects of actions that mediate initiation, persistence, termination, and inhibition. Since the interhemispheric axons of the corpus callosum are especially susceptible to shearing from torsional forces during traumatic brain injury (TBI), the goal of this study was to learn whether participants with a history of severe traumatic brain injury demonstrate three types of cognitive–motor impairments that may result from callosal injury: ideomotor apraxia of the left hand, limb kinetic apraxia of the left hand, and hypokinesia of the right hand in response to left hemispatial stimuli. Method: Nine participants with severe TBI and nine healthy control participants were studied for the presence of ideomotor apraxia, limb kinetic apraxia, and hypokinesia. Results: When compared to the control participants, the participants with TBI revealed ideomotor apraxia and limb kinetic apraxia of the left hand and hypokinesia in response to left-sided visual stimuli when tested with the right hand. Conclusions: TBI appears to cause unilateral disorders of cognitive–motor functions. Future research is needed to understand how these cognitive–motor disorders are related to interhemispheric disconnection most likely induced by injury to the corpus callosum.

Affective communication deficits associated with cerebellar degeneration

The cerebellum has extensive connections with the frontal lobes. Cerebellar injury has been reported to induce frontal-executive cognitive dysfunction and blunting of affect. We examined a patient with idiopathic cerebellar degeneration with impaired family relationships attributed to an “emotional disconnection.” Examination revealed ataxia, dysmetria, and adiadochokinesia more severe on the left and frontal-executive dysfunction; memory and cognitive functions were otherwise normal. Testing of emotional communication included assessments of emotional semantic knowledge, emotional prosody, and emotional facial expressions. Comprehension was normal but expression was severely impaired. Cerebellar dysfunction can cause a defect in facial and prosodic emotional communication.