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Biomedical subjects

J M Notterman

Publications and source records attributed to J M Notterman.

8 recordsLinked to original sources
PubMed1987

Individual differences in ability to use EMG-derived feedback.

Evidence shows statistically reliable individual differences among unimpaired subjects in ability to use visual representation of electromyographic voltages. The visual information was displayed as a cursor in a tracking situation. The cursor was then blanked, with subjects being required to place the now invisible cursor over a target. Test-retest correlational significance is demonstrated. The rationale for using visual guidance in rehabilitating stroke victims suffering from loss in motor feedback receives support.

Adolescent↗
PubMed1982

Visual-motor organization: differences between and within individuals.

The research described in this monograph uses control theory's pursuit-tracking paradigm of voluntary movement to identify several elementary psychomotor tasks. They are simple to administer and tap increasingly complex, nonverbal cognitive or perceptual attributes. Two series of experiments are reported. Study 1 examined the hypothesis that dissimilar arrays of individual differences, as determined through test-retest correlations, may exist among the same subjects: first, across various static and dynamic visual and motor "tasks" selected from the terms of control theory's tracking equations and, second, in the organization of these tasks as represented by pursuit tracking. The hypothesis could not be rejected. Study 2 determined that test-retest individual differences in visual-motor organization not only persisted in the absence of practice, but that they also withstood active intervention by practice. This study also showed that subjects differ reliably in their ability to plan, i.e., to take advantage of coherence in visual-motor information.

Concept Formation↗
PubMed1981

Organization and learning of visual-motor information during different orders of limb movement: step, velocity, acceleration.

Theoretical use of the tracking paradigm as a means of understanding perceptual-motor organization has been influenced by ambiguous assumptions concerning the relation of time orders of force production to the learning and performance of time orders of limb movement. This study provides both a conceptual framework for clarifying these assumptions, and empirical data for testing them. The independent variables were (a) target motion (step, velocity, acceleration); (b) stick loading (elasticity, damping, mass); and (c) practice. The dependent variables were absolute terror for step and time-integrated squared error for velocity and acceleration. The hypothesis was that proficiency of tracking is inversely related to mathematical complexity of reactive forces, within constraints imposed by familiarity with required types of transfer functions. Five subjects were assigned to track one type of target motion in each of the three loading conditions, respectively. Cursor-present "training" trials were alternated with cursor-absent "test" trials. Thereby, a premium was placed on attention to proprioceptive feedback, at least at the start of training. The hypothesis could not be rejected.

Adult↗
PubMed1980

Variables influencing outflow-inflow interpretations tracking performance: predictability of target motion, transfer function, and practice.

Experimental evidence can be found in support of either outflow or inflow theories of voluntary action. Accordingly, the empirical problem becomes one of ascertaining fundamental conditions under which the dichotomy plainly manifests itself. Using a within-subjects design, six undergraduates were given pursuit tracking training. The independent variables were (a) presence or absence of regularity (predictability) in the back-and-forth motion of the target, (b) type of control stick (with attendant proprioceptive feedback) used to drive the cursor, and (c) practice. The dependent variable was the time integral of error. The following results were significant (p less than .05, two-tailed): (a) A pressure stick is better than a freely moving one when tracking a random target; this finding supports a reactive force inflow model. The converse is true for a predictable target and is therefore supportive of an outflow interpretation. (b) Regardless of kind of target motion, an unloaded stick is better than an elastically loaded one at the beginning of training (outflow support) but worse by the end of training (inflow support). It is concluded that the motor outflow versus motor inflow dispute is amenable to parametric resolution.

Cues↗
PubMed1971

Perception of changes in certain exteroceptive stimuli.

Although cybernetic models of one sort or another have become quite common in behavioral research, and although these models theoretically require a capacity for system detection of changes in error, no general psychophysical description of the individual human being's ability to discriminate different rates of stimulation is available. An initial survey of this type has been attempted and is reported here. For reasons which appear to be related to the biological mechanisms underlying sensory information processing, it is concluded, first, that ancillary cues of rate-related final magnitude are more valuable than cues of stimulus duration; second, that direct attention to on-going change is less precise than attention to final values only; and third, that differences in isochronal stimulus rates occurring in place or extent are more readily perceived than differences in isochronal rate of change in energy content, at least for the stimuli and ranges examined.

Auditory Perception↗