Vision and kinesthesis in accuracy of hand movement.

Two experiments examined the accuracy with which college students were able to touch a target when knowledge of the target location had been gained either visually, kinesthetically, or by both modalities. In all but "baseline" trials, individuals were not allowed to guide the hand visually and so relied on kinesthetic cues during movement to the target location. No feedback was provided. Contrary to students' expectations, accuracy of the movements was greater when the target location had been given kinesthetically (passive movement to the target) as opposed to visually. When target location was provided by seeing one's hand move to the target (kinesthetic plus visual), performance was slightly poorer (though nonsignificantly) than for the purely kinesthetic condition, but significantly better than for a purely visual target condition. These results are discussed in terms of visual dominance and the roles of vision and kinesthesis in guiding normal hand movements.

Vision, kinesthesis, and control of hand movement by young and old adults.

This study examined the accuracy with which 20 young (18 to 24 yr.) and 32 old (55 to 85 yr.) adults were able to move their hands when not allowed to guide them visually. They tried to touch a target spot given either visually or kinesthetically, under conditions in which the target either remained present during the response or was discontinued prior to the response. They also tried to touch points on the face with eyes closed and wrote their names and common words with and without visual input. While there was slight evidence of age-related decline in accuracy of moving the hand to a target location in some conditions, older adults appear to use kinesthetic cues to the target location as effectively as visual cues. The absence of age effects on touching the face or writing with the eyes closed suggests that the kinesthetic and motor control systems are relatively well preserved in healthy older adults.

The role of vision in sound localization.

Three experiments examined the role of vision in locating a brief sound (2-sec. speech noise) from an unseen source in the horizontal left front quadrant. The head could be freely moved. Subjects could point to the sound location more accurately with eyes open. However, since in a second study the accuracy of pointing a finger was poorer than for aiming one's eyes at the sound, the effect in the first study may reflect using vision to calibrate the hand location. A third study showed no difference in accuracy of aiming one's eyes at a sound when eyes were open versus closed during presentation of sound. More accurate auditory localization with eyes open than closed was not supported.

Prediction and evaluation of memory performance by young and old adults.

Does the poorer performance of older people in laboratory tests of episodic memory result from metamemory problems? Memory of 20 young and 20 old adults for 60 "unrelated" paired associates was measured by an associative matching task. Two metamemory measures also were taken: Each pair was rated at the time of study for the likelihood that the person would recall it (prediction measure) and on the matching task each response pairing was judged as to its correctness (response evaluation measure). Young adults were correct on 50% of the associative matches, old only 30%. The two groups did not differ in the predictive metamemory measure: Both were able to predict relative memorability. Old persons, however, underestimated task difficulty (i.e., they overestimated the number of correct associative matches they would make, whereas the young did not). Both groups were quite accurate in the response evaluation measure.

Stimulus encoding selectivity at high degrees of paired-associate learning.

Sixty-two Ss learned six CCC trigram-digit pairs by the study-test method; 21 Ss continued the PA acquisition trials to a learning criterion of one errorless trial, while 41 Ss were carded to 300% overlearning or 24 trials, whichever came first. The Ss were then shown individual letters of the trigrams, with position cues provided, and were tested for their ability to provide the digit and produce the additional letters. Digit recall was much better to initial letters than to those in the second or third positions of the trigrams; with oveflearning, digit recall improved to the initial letters but not to letters in second and third positions. Production of additional letters of the trigrams was not appreciably related to either cue position or degree of PA learning. There was some evidence ofincreased selectivity with higher degrees of PA learning.

Free associations of older adults to single words and conceptually related word triads.

Verbal free association responses were elicited to 56 single-word stimuli and 30 triads of conceptually related words from 95 older adults (52 to 90 years) and 31 younger adults (23 to 49). For single words, the distribution of paradigmatic and syntagmatic associations was similar for the older and younger samples; multiple regression analysis indicated that, although vocabulary scores were a good predictor of type of response, age was not. Specific responses to single words were similar for older and younger adults; there was some evidence of a slight reduction in commonality of associations with aging. For triad stimuli, the levels of responses reflecting shared membership in a natural category or a shared characteristic (sensory) feature were similar for younger and older adults; again vocabulary scores consistently predicted such responses, but age did not.