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Kirsten McKenzie

Publications and source records attributed to Kirsten McKenzie.

6 recordsLinked to original sources

Parietal updating of limb posture: an event-related fMRI study.

The posterior parietal cortex (PPC) is thought to integrate different kinds of sensory information (e.g., visual, auditory, somatosensory) to produce multiple representations of space that are each associated with different types or combinations of action; such as saccadic eye movements and reaching or grasping movements of the upper limb. Lesion studies in monkeys and in humans have shown that reaching movements to visually defined and to posturally defined targets can be dissociated from one another; indicating that different regions of the parietal cortex may code the same movement in either extrinsic (visual) or intrinsic (postural) coordinates. These studies also suggest that regions within the posterior parietal cortex play an important role in maintaining an accurate and up-to-date representation of the current postural state of the body (the body schema). We used event-related functional magnetic resonance imaging (fMRI) to investigate those brain areas involved in maintaining and updating postural (i.e., non-visual) representations of the upper limb that participate in the accurate control of reaching movements. We show that a change in the posture of the upper-limb is associated with a significant increase in BOLD activation in only one brain region--the superior parietal cortex, particularly the medial aspect (precuneus). We note that this finding is consistent with the suggestion, based upon human neurological investigations and monkey electrophysiology, that this region of the PPC may participate in the dynamic representation of the body schema, and is the most likely location for damage leading to errors in visually guided reaching to non-foveated target locations. We also note that this brain area corresponds to a region of PPC recently identified as the human homologue of the Parietal Reach Region (PRR) observed in the monkey brain that has been thought to represent reaching movements in eye-centred coordinates.

Adult↗

The quality of cause-of-injury data: where hospital records fall down.

OBJECTIVES: This research identifies the level of specificity of cause-of-injury morbidity data in Australia. The research explores reasons for poor-quality data across different causes-of-injury areas, including a lack of clinical documentation and insufficient detail in the classification system. METHODS: The 2002/03 hospital morbidity dataset of 593,079 injury-related hospital admissions was analysed to examine the specificity of coded external cause-of-injury data. RESULTS: While overall specificity appeared high, the cause of 47,660 injuries was not specifically defined according to the code assigned. Only 56% of cases for whom injury was the result of an accidental fall were assigned a specific code to identify the causal detail; 19% were assigned an 'Other Specified' fall code, suggesting a lack of specific code availability; and 25% were assigned an 'Unspecified Fall' code, suggesting a lack of clinical documentation to facilitate code selection. CONCLUSIONS: To improve the quality of injury-related hospital morbidity data, two main areas to focus resources are: 1) the development of more specific cause-of-injury codes; and 2) the provision of more detailed documentation from clinicians. IMPLICATIONS: Clinicians and clinical coders need to work together to improve the quality of injury-related coded data through the provision of specific codes and improved clinical documentation. Accurate and comprehensive data pertaining to the circumstances surrounding hospitalised injury events will benefit injury prevention and surveillance initiatives, provide justification for resources related to injury hospitalisation, and assist in external cause research in Australia.

Adult↗