Kenneth M. Heilman, Ph.D. - US grants

Liepmann and Maas (1907) suggested that the left hemisphere contains movement formulas that program the timing and spatial relationships of skilled movements bilaterally. Although patients with ideomotor apraxia from the left hemisphere lesions made errors when gesturing to command or imitating a gesture, the nature of the errors made by these patients and its anatomic correlate have not been systematically analyzed. Patients with ideomotor apraxia may also have difficulty discriminating and comprehending gestures. The nature of these discrimination and comprehension defects have also not been fully explored. The purpose of this experimental program is to better define the gesture production and reception errors associated with ideomotor apraxia and see how these errors may relate to different anatomic lesions. This proposal contains five experiments. The first experiment examines the apraxic patients' production errors. Apraxic patients' production errors will be qualitatively and quantitatively analyzed and scored. The second study attempts to learn what parameters of a complex movement cause discrimination disorders in apraxic patients. The third experiment tests the hypothesis that apraxic subjects have more difficulty performing movements executed in extra-personal space than they do in performing movements in intra personal space. Experiment four attempts to learn if the gesture comprehension disorder exhibited by apraxic patients is related to a movement disorder or a language disorder. Experiment five examines how the dichotomy of abstract vs. concrete pertains to apraxic patients' performances.

Patients with right hemisphere lesions (RHD) often demonstrate flattened affect, decreased arousal, and a variety of emotional communicaitons disorders. A previous study suggests that RHD patients also recall emotional versus non-emotional stories less well than normal or left hemisphere damaged (LHD) patients. The present proposal attempts to elucidate some of the neuropsychological characteristics of this memory disturbance and its anatomic correlation. Three studies are proposed in which RHD, LHD, and non-brain-damaged patients are examined on a variety of different emotional memory tasks. Experiment I assesses the ability of RHD patients to spontaneously acquire emotional and non-emotional words using a work list learning paradigm. Experiment 2 uses a "levels of processing" paradigm to determine whether directed attention to emotional and semantic messages at the time of "encoding" differentially facilitates memory performance. Experiment 3 assesses the ability of RHD patients to recall emotional experiences from remote memory. Throughout these studies, we plan to measure psychophysiological responses and to correlate these measures with memory performance and locus of injury.

Theoretical models that deal with praxis divide the action plan into two major components: an executive-conceptual system and a production system. We define ideational apraxia as a conceptual disorder where a brain damaged patient has lost conceptual knowledge related to tool use and not necessarily performance knowledge. We propose that this conceptual disorder may occur at 3 different levels: 1. a brain damaged patient may not be able to associate a tool or instrument with the object or objects that usually receive the action of that tool. For example, a patient may not be able to associate a hammer with a nail (tool object relationship knowledge). 2. A patient may have lost knowledge as to what type of mechanical action is performed by a given tool or what type of mechanical action is needed to complete an act (tool action relationship knowledge). For example, when given a hammer, one should pound rather than twist. 3. Lastly, a patient may fail to understand the mechanical nature of problems as well as the mechanical advantages that tool may afford (mechanical knowledge). In this grant, we plan to study these potential conceptual disorders in patients with lateralized brain damage. Although it is possible that tool-object knowledge, tool action knowledge and mechanical knowledge may be diffusely or bilaterally represented, it has been well established that in man much of our knowledge about the world is represented unilaterally or asymmetrically. We therefore want to learn if the concepts about tool use are also asymmetrically or unilaterally presented. De Renzi, et al. suggested that ideational apraxia is associated with language comprehension disorders. Our planned studies will attempt to learn if these conceptual disorders are or are not related to language comprehension disorders. We also want to learn if disorders of the praxis conceptual system are related or can occur independently of disorders in the praxis production systems. Lastly, we want to learn the nature of the anatomic lesions that are associated with these praxis executive disorders.

DESCRIPTION (Investigator's Abstract): Unawareness of a deficit or anosognosia is commonly associated with brain dysfunction and often interferes with rehabilitation. Unfortunately the neuropsychological mechanisms associated with anosognolia are poorly understood Recently we observed that unawareness of hemiplegia (anosognosia) can be induced by WADA testing (intracarotid barbiturate anesthesia). The purpose of this study is to use the wada procedure to test several neuropsychological hypotheses. Experiment I will attempt to determine if anosognosia can be attributed to a memory defect. Experiment II will examine the relationship between anosognosia and personal neglect (asomatognosia) and partially test Geschwind's disconnection hypothesis. Experiment III will test the feed forward or intention.activation hypothesis.

DESCRIPTION: (Verbatim from the Applicant's Abstract) Spatial neglect impairs a person's ability to interact with their environment. Many of the symptoms of neglect can be induced by unilateral hemispheric injections of neurotoxins that unilaterally impair the dopaminergic systems. However, on standard test of neglect most patients with Parkinson's disease (PD) do not demonstrate neglect. PD patients most often have bilateral dopamine dysfunction and the failure to find unilateral neglect in these patients may be related to the bilaterality of this disease. There have been several reports of patients with bilateral lesions who had neglect of near or far peripersonal space. To learn if patients with PD may be neglecting far peripersonal space, we performed a pilot study. In this study we attempted to learn if the perceived size of lines or amplitude of movements were influenced by the spatial location of the stimulus in respect to the body. We found that when PD subjects perceived lines close to their body (medial) and tired to move an equal distance laterally they were hypometric. However, when they prceived a line laterally and movements centrally (medial) they were hypometric. These results suggested to us that patietns with PD may have either an abnormal perception of space, an abnormal response pattern or both. The purpose of this program is to further study Parkinson's patients spatial perceptions ad motor action sot learn if far peripersonal space is represented differently than near peripersonal space

human therapy evaluation; emotions; psycholinguistics; aphasia; face expression; rehabilitation; training; medical rehabilitation related tag; functional magnetic resonance imaging; brain imaging /visualization /scanning; human subject; clinical research;

DESCRIPTION (provided by applicant): The cerebellum has been linked to cognitive and emotional functions and there is increasing evidence that damage to posterior portions of the cerebellum can result in frontal-executive, visuospatial, and expressive deficits, including dysprosodia, and affective changes including blunting of affect or disinhibited and inappropriate behavior (Stoodley & Schmahmann, 2010; Schmahmann & Sherman, 1998). Based on preliminary clinical observations and tests performed in our clinic, disorders of emotional communication may also be associated with cerebellar dysfunction (Heilman, et al,. 2012). Emotional communication includes the production and comprehension of facial and prosodic expressions and is critical to maintaining positive and supportive relationships. Deficits in emotional communication can have devastating effects on relationships and on quality of life for those affected (Blonder et al., 2012). Although deficits in affect and prosody have been reported in association with posterior cerebellar disorders, there are currently no studies systematically investigating emotional communication in individuals with cerebellar dysfunction. It is known that the cerebellum has strong connections with the cerebral cortex, especially the frontal lobes, and that cortical damage from stroke or neurodegenerative disease can result in disorders of emotional communication (Tucker, Watson & Heilman, 1977; Heilman, Leon, & Rosenbek, 2004; Ross & Mesulam, 1979). Impairments in the integrity of cerebellar-cerebral networks from cerebellar disease may produce similar deficits in emotional communication. The purpose of this study is to systematically investigate and describe deficits in emotional communication in a series of patients with cerebellar disease. Method. Participants will be 40 individuals diagnosed with posterior cerebellar degeneration or damage from a non-hemorrhagic infarction, and 40 age-matched neurologically healthy controls. Assessment will include a battery of tests of neuropsychological function as well as tests of emotional communication. Comprehension of emotional facial and prosodic expressions will be assessed using the Florida Affect Battery (Bowers et al., 1998). Production of emotional communication will be evaluated by performance on the Florida Emotional Expressive Battery. Facial and prosodic expressions will be recorded and independently rated by trained judges. We will also assess reactivity to emotionally evocative pictures and words using materials with established rating norms (Bradley & Lang, 1999; Lang, Bradley, & Cuthbert, 2008) as well as comprehension and production of propositional emotional language. Outcomes. The expected outcomes will be to identify and describe deficits in production and comprehension of emotional communicative deficits (verbal and nonverbal) and to identify and describe alterations in reactivity to emotionally evocative stimuli in individuals with cerebellar disease. Little is currently known about the role of cerebellar-cerebral connections in emotional communication disorders and greater understanding may result in innovative approaches to treatment for these debilitating disorders.