Novel associative processing and aging: effect on creative production.

Creative production has been reported to decline with age. This study investigated age-related differences in creative verbal production. Participants were 30 younger and 30 older adults. Study testing included language and cognitive assessments and the experimental task wherein participants created short stories incorporating words that are not commonly related, semantically or associatively. The resulting stories were rated by independent blinded judges for originality, cohesion, appropriateness, and organization. Younger adults' stories were rated as being significantly more original and more appropriate. Integrating unrelated words to create original stories requires activating widely distributed lexical-semantic networks to develop novel associations. Potential decreased neural network connectivity due to white matter degradation, commonly seen in normal aging, as well as decrements in front-executive disengagement may have affected older adults' performance on this story creation task. Future research using neuroimaging may elucidate possible neuroanatomic correlates of age-related changes in associative creative production..

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.

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

Divergent thinking is the ability to produce a range of responses or solutions and is an element of creative processing. Divergent thinking requires disengagement, the ability to associate between words or ideas, and the production of responses. Lesion and imaging studies have shown frontal-lobe involvement for these activities, and frontal lobe function is highly dependent on white matter pathways. Normal aging often results in deficits in functions controlled by the frontal lobes as well as decrements in white matter connectivity. The objectives of this study were to compare non time-constrained tasks of verbal divergent processing in young adults (YAs) and older adults (OAs) and correlate 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. The authors propose that the primary factor resulting in higher uniqueness scores for the OAs was a greater wealth of experience as well as longer exposure to language use.

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

Six individuals with probable Alzheimer's 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.

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.

Effects of two treatments for aprosodia secondary to acquired brain injury.

Expressive aprosodia is an impaired ability to change one's 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.

Active treatments for aprosodia secondary to right hemisphere stroke.

This study investigates the effects of two mechanism-based treatments for expressive aprosodia. Three participants, two women and one man, had a right hemisphere cerebral infarction resulting in affective aprosodia with greater expressive than receptive deficits. Trained raters determined presence of aprosodia by judging participants' performance on two emotional communication batteries. A single-subject design with replication across three participants was employed. Sentence production with the use of treated and nontreated emotions was measured during baseline and treatment phases. Sentences were scored for accuracy by a trained rater blind to time of testing and analyzed visually and statistically. Effect sizes calculated on the resulting data for each participant and treatment confirmed modest to substantial treatment effects for both treatments in all three participants. Because of a relative paucity of treatment studies investigating expressive aprosodia, these data are among the first to suggest that aprosodia may be amenable to behavioral treatments.

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 CVA's 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.

Affective aprosodia from a medial frontal stroke.

BACKGROUND AND OBJECTIVES: Whereas injury to the left hemisphere induces aphasia, injury to the right hemisphere's 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.