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J D Hagman

Publications and source records attributed to J D Hagman.

3 recordsLinked to original sources

Presentation- and test-trial effects on acquisition and retention of distance and location.

Acquisition and retention effects of presentation and test trials on movement distance (Experiment 1) and location (Experiment 2) were examined under three multitrial training methods. Three groups of 15 government employees performed three training trial cycles consisting of six trials each. Training methods emphasized either presentation-trial repetition, test-trial repetition, or presentation- and test-trial alternation within cycles. After training, both short- (3 min.) and long-term (24 hr.) retention scores were recorded. Absolute error revealed that (a) presentation-trial repetition promoted acquisition of both distance and location but resulted in extensive short- and long-term forgetting; (b) test-trial repetition produced error increases within cycles, potentiated presentation-trial effectiveness during acquisition, and enhanced long-term retention of both distance and location; (c) presentation- and test-trial alternation promoted distance and location acquisition and produced distance retention intermediate to that of the other two methods. Experiment 3 provided data to support the interpretation that test-trial retention benefits are a function of movement execution mode.

Adult↗

Use of distance and location in short-term motor memory.

A retroactive interference paradigm was used to determine whether kinesthetic distance, location, or distance and location cues are used at recall of a blind, simple linear movement. Students performed interpolated movements which varied distance and location cues separately or jointly. Relative to a rest condition, joint distance and location interpolation produced significant interference while no significant interference was found for interpolation of individual distance or location. The results were interpreted as supporting the involvement of multiple kinesthetic cues in the establishment of memorial representations of motor movements.

Cues↗

Stimulus intensity effects in electrodermal habituation.

Experiment 1 presented human subjects with 25 shocks of the same (.5, 1.5, or 2.5 mA:between-subjects design) or different (.5, 1.0, 1.5, 2.0, and 2.5 mA:within-subjects design) intensities to test predictions of the dual-process, cortical-model, and adaptation-level theories concerning terminal electrodermal response (EDR) magnitudes in an habituation paradigm. Dual-process theory correctly predicted terminal EDR magnitudes and relative EDR habituation rates. Dual-process theory was further supported in Experiment 3 when EDR magnitude to a standard intensity shock (1.25 mA) decreased with the intensity of a second comparison shock (0, .5, 1.25, or 2.5 mA) only up to the 1.25-mA level, as the common-elements construct of the dual-process theory predicts. Adaptation level incorrectly predicted that standard stimulus EDR magnitude would decrease as comparison intensity, hence adaptation level, increased. Forewarning subjects of each shock intensity increased EDR magnitude in Experiments 2 and 3 contrary to the cortical-model theory's prediction based on subjective stimulus uncertainty.

Adaptation, Physiological↗