Biomedical subjects

B Hanna-Pladdy

Publications and source records attributed to B Hanna-Pladdy.

6 recordsLinked to original sources

PubMed2003

Ecological implications of ideomotor apraxia: evidence from physical activities of daily living.

OBJECTIVE: To learn if ideomotor apraxia (IMA) adversely influences skilled acts in the environment and interferes with independent functioning after stroke. METHODS: The relationship between IMA severity, based on scores from a verbal gesture-to-command (pantomime) task, and the dependency score, as defined by increased caregiver assistance on the Physical Self-Maintenance Scale (PSMS), was investigated in 10 unilateral left hemisphere-damaged stroke patients and 10 matched control subjects. RESULTS: There was a significant relationship between apraxia severity and dependency in physical functioning (PSMS). Impairment on the PSMS in the patients with IMA could not be accounted for based on overall cognitive impairment, poststroke depression, content-conceptual errors, elementary motor impairment, lesion size, or stroke-test interval. Analysis of categories composing the PSMS revealed that the patients with apraxia had increased dependency in grooming, bathing, and toileting relative to age-matched control subjects. CONCLUSIONS: These findings emphasize the ecological implications of apraxia and the need for rehabilitation strategies to improve the execution and efficiency of coordinated skilled movements in stroke patients with left hemisphere damage.

Activities of Daily Living↗

PubMed2002

Lateralised motor control: hemispheric damage and the loss of deftness.

OBJECTIVE: To learn if the left compared with the right hemisphere of right handed subjects exerts bilateral compared with contralateral motor control when performing precise and coordinated finger movements. METHODS: The study investigated intertask differences of manual motor asymmetries such as speed, precision, and independent finger movements, in patients with unilateral lesions of the left (LHD) or right hemisphere (RHD) and normal controls (C). RESULTS: Normal subjects showed the greatest right hand preference on a task that required rapid coordinated and precise independent finger movements (coin rotation). Both hemisphere damaged groups revealed contralateral motor deficits, but the magnitudes of asymmetries were found to be significantly different (RHD>C>LHD) with contralateral and ipsilateral deficits for LHD subjects. The greatest ipsilateral deficits for the LHD subjects were on those tasks that require precision (grooved pegboard and coin rotation). CONCLUSIONS: The degree of hemispheric specialisation is, in part, dependent upon the nature of the motor task, with left hemisphere motor control necessary for tasks that require precision and coordinated independent finger movements.

Adult↗

PubMed2001

Praxis lateralization: errors in right and left hemisphere stroke.

Whereas the representations of skilled movements in most right handers are stored in the left hemisphere, the right hemisphere's contribution to action planning remains unclear. We investigated error patterns in left (LHD) and right hemisphere damaged (RHD) subjects as well as normal control subjects (C) to determine if specific components of action programs may be processed by the right hemisphere or bilaterally represented. We had these subjects perform gestures to verbal command with the ipsilesional limb. Although the LHD group made significantly more qualitative errors than the C and RHD groups, the RHD subjects produced a number of apraxic errors. Specifically, the LHD group produced a wide range of spatiotemporal and conceptual errors for both transitive and intransitive gestures, while the RHD group made specific spatial and temporal errors primarily when performing transitive gestures. These findings support the postulate that the left hemisphere stores the spatiotemporal and conceptual representations of learned skilled movements, while several specific components of action programs, such as external configuration (limb orientation) and timing, may have bihemispheric representations.

Aged↗

PubMed2001

Stress as a diagnostic challenge for postconcussive symptoms: sequelae of mild traumatic brain injury or physiological stress response.

There is considerable controversy regarding whether persistent postconcussive symptoms (PCS) are injury-specific, in a subgroup of individuals after mild traumatic brain injury (TBI). The following findings have contributed to this controversy: (1) The base rate of PCS in mild TBI is comparable to uninjured controls; and (2) The severity of PCS covary with daily stress levels (Gouvier, Cubic, Jones, Brantley, & Cutlip, 1992). We examined this relationship further by evaluating the effects of experimental conditions of stress or relaxation on individuals with TBI and uninjured control subjects, with low and high PCS endorsement. We evaluated psychophysiological parameters, neuropsychological performance, and changes in PCS and stress perception. In our study, subjects with TBI increased PCS after engaging in cognitively challenging tasks, and demonstrated significant autonomic changes in the stress condition. Symptomatic TBI subjects exposed to high stress had increases in PCS complaints, decreased speed of information processing, and subtle memory deficits. Our results suggest that PCS are injury-specific and that individuals with a history of TBI are susceptible to the effects of stress. Relaxation training including breathing retraining may be an effective means of decreasing PCS and cognitive complaints in subjects with mild TBI.

Adult↗

PubMed2001

Cortical and subcortical contributions to ideomotor apraxia: analysis of task demands and error types.

Ideomotor apraxia (IMA) is often associated with damage of the dominant parietal cortex, but many other lesion sites have been implicated suggesting that the praxis system is mediated by a distributed modular network. Although IMA has been reported with subcortical lesions, the role of subcortical structures in the praxis neural network has not been fully addressed. To ascertain the role of subcortical structures in praxis, we compared praxis performance on a variety of tasks in patients with left hemisphere cortical and subcortical lesions. The cortical patients presented with deficits in the production of transitive and intransitive gestures-to-verbal command and imitation, as well as impaired gesture discrimination. In contrast, the subcortical group demonstrated mild production-execution deficits for transitive pantomimes, but normal imitation and discrimination. Qualitative error analysis of production deficits, revealed that both patient groups produced timing errors and the full range of spatial errors. Whereas the subcortical group made more postural errors than the cortical group, sequencing, unrecognizable and no-response errors were only produced by the cortical group. The different profiles of praxis deficits associated with cortical and subcortical lesions, suggests that these structures may have different roles in praxis.

Aphasia↗

PubMed2000

Head injury as a predictor of psychological outcome in combat veterans.

Although it is recognized that psychosocial variables influence the expression of psychopathology following trauma exposure, physiological variables have received less attention as potential mediators of psychological outcome in trauma victims. The purpose of this study was to examine the relationship of head injury to psychological outcome in 171 combat veterans seeking compensation for service-connected disabilities for mental disorders attributed to etiologies other than head injury. Veterans underwent structured psychiatric diagnostic interview and completed self-report measures of combat exposure, posttraumatic stress disorder (PTSD), depression, and occurrence of head injury. Comparisons between veterans with and without history of head injury indicated that head injury was associated with more severe depression. Regression analysis suggested that head injury predicted depression, but not PTSD, severity.

Adult↗