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D Goldthwaite

Publications and source records attributed to D Goldthwaite.

5 recordsLinked to original sources
PubMed1999

The effect of orientation on the clarity of Hermann grid illusory lines.

To test the hypothesis that Hermann grid illusory lines are most clear when the grid is presented at a 45 deg, each of 20 participants underwent 10 trials in each of two conditions ('make the lines least clear' and 'make the lines most clear') which were run using a method of adjustment. A matched-pairs t-test applied to the means of the two conditions was significant beyond the 0.01 level. One-group t-tests supported the claim that the illusory lines are least clear for a vertical/horizontal orientation of the grid and most clear when it is rotated 45 deg. The results substantiate, in a systematic manner, 70 years of claims about the effects of grid orientation on illusory line clarity.

Adult↗
PubMed1997

Knowledge of pragmatic conversational structure.

Knowledge of conversational pragmatic structure was examined by asking 53 female volunteers to rate the naturalness of three versions of an appointment-making conversation from a beauty salon. One version was the naturally occurring conversation. The other two were its two most frequent reconstructions created by a separate group of subjects asked to put the scrambled natural conversation "back together again." A chi-square test and standardized deviates showed that the naturally occurring conversation was rated as the most natural one. This result is attributed to subjects' implicit knowledge about conversational pragmatic structure. The role that this knowledge might play in language comprehension is discussed.

Adolescent↗
PubMed1976

A study of dark adaptation in ocular hypertensives.

Previous studies of dark adaptation in glaucoma have been hampered by lack of standardization and poor definition of clinical categories. A new method of testing has been used on ocular hypertensives. A modified Goldmann/Weekers adaptometer and an 11 degree centrally fixated test patch were used to obtain two dark adaptation threshold curves for each subject -- one for blue-green and one for yellow. Results indicate that ocular hypertensives with no field loss and normal fundi have impaired normal subjects. The differences in the thresholds for blue-green were especially noticeable with the blue-green showing the greater difference. The 2.8 minute difference in mean curve cross-over time between normal and ocular hypertensive was also found to be significant. It appears that ocular hypertensives have impaired rod and cone functions, as well as deficient rod-cone interaction.

Animals↗