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The fractal analysis of stride-to-stride fluctuations in walking has become an integral part of human gait research. Fractal analysis of stride time intervals can provide insights into locomotor function and dysfunction, but its application requires a large number of strides, which can be difficult to collect from people with movement disorders such as Parkinson’s disease. It has recently been suggested that “stitching” together short gait trials to create a longer time series could be a solution. The objective of this study was to determine if scaling exponents from “stitched” stride time series were similar to those from continuous, longer stride time series. Fifteen young adults, fourteen older adults, and thirteen people with Parkinson’s disease walked around an indoor track in three blocks: one time 15 min, five times 3 min, and thirty times 30 s. Stride time intervals were determined from gait events recorded with instrumented insoles, and the detrended fluctuation analysis was applied to each stride time series of 512 strides. There was no statistically significant difference between scaling exponents in the three blocks, but intra-class correlation revealed very low between-blocks reliability of scaling exponents. This result challenges the premise that the stitching procedure could provide reliable information about gait dynamics, as it suggests that fractal analysis of stitched time series does not capture the same dynamics as gait recorded continuously. The stitching procedure cannot be considered as a valid alternative to the collection of continuous, long trials. Further studies are recommended to determine if the application of fractal analysis is limited by its own methodological considerations (i.e., long time series), or if other solutions exists to obtain reliable scaling exponents in populations with movement disorders.

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The DASH score is a universally accepted method for assessment of hand function. However, there are occasions when a pre-treatment DASH score is unavailable. This study provides a solution to this situation. An initial DASH score was obtained from all patients at the time of their first clinic visit. A second score was obtained at the time of final follow-up asking the patient to "Recall" their pre-treatment status. The two scores were compared with appropriate statistical analysis. Thirty-eight patients were included in the study and scores were obtained at an average time interval of 32 weeks (6-121 weeks). Excellent agreement was noted for the ability of the patient population to recall their scores with a group correlation of 0.86. This proves that the Recall DASH score is an excellent and useful research tool for use in hand surgery.

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A same-different matching task was used to investigate how subjects perceived a dichotic pair of pure tones. Pairs of stimulus tones in four frequency ranges (center frequencies of 400-1,700 Hz), with separations between 40 and 400 Hz, were tested. Five types of test tones were matched to the stimulus pair: the stimulus pair presented again (control) or crossed over (same tones, different ears), the geometric mean of the two tones, or a binaural tone of the low or high tone of the pair. In the lowest frequency range and the highest with maximum separation, the crossed-over test tones were perceived as different from the same stimulus tones. A bias for perceiving the higher tone of a pair was evident in the frequency ranges with separations of 40-200 Hz. In the lowest frequency range, the bias was for perceiving the higher tone in the right ear. This restricted ear advantage in the perception of pure tones was not significantly related to the right-ear advantage in dichotic word monitoring.A common finding in speech perception research is that the speech signal contains redundant acoustical information. This has been amply demonstrated by the ability of researchers to "paint" their own spectrograms, which bear little resemblance to actual speech spectrograms but carry sufficient information to allow for the perception of speech content (Liberman, Cooper, Shankweiler, & StuddertKennedy, 1967). Several information processing models have implied the existence of filtering mechanisms at the input stages of an information channel (Broadbent, 1971), and it may be hypothesized that some form of filtering takes place in the auditory system to separate complex signals into relevant and irrelevant components.One method of ascertaining what remains of the signal after it has been processed is to present a complex signal followed by a component of the signal and to ask the subject whether the two inputs were the same or different. If the subject says that the inputs were the same, it is likely that the part of the original stimulus not included in the matching stimulus was filtered out, assuming that the subject does not also match what was supposedly filtered out to the original stimulus. This is the method employed in the present study. Only two input stimuli were used (both being pure tones), and determinations were made as to which stimulus dominated the percept. To offset any interactions of the two stimuli along the basilar membrane, stimuli were presented dichotically (i.e., a different stimulus to each ear) and the matching This study was supported by an ARGC grant to Gina Geffen. We are grateful to Kustas Tiivas for software development on the tone perception task. stimuli were presented binaurally (one of the two components of the original stimulus presented to both ears).This method allows for the testing of two possible. types of dominance, ear or stimulus dominance (or some combination of the two). Several studies have examined ear differences in the perception of dichotic pure-tone stimuli. Deutsch (1974Deutsch...

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