19, D38106 Braunschweig, Germany ( 1 JOHN C. BAIRD Psychological Applications, Newport, New Hampshire , Dartmouth Medical School , Lebanon, New Hampshire , and Dartmouth College , Hanover, New
A series of experiments considers the extent to which the interrelations among subjective magnitudes aroused by images corresponds to those for subjective magnitudes aroused by physical stimuli. In Experiment 1,68 undergraduates typed phrases in response to graded categories regarding the imagined magnitude of lights, sounds, and smells. In Experiment 2,5 undergraduates and, in...
The human channel capacity for identifying sensory stimuli is compared with channel capacities based on neurophysiological findings. Studies have shown that cells in the postsubiculum (PoS) and the anterior dorsal thalamus (ADN) of the rat discharge as a function of the animal’s head direction in the horizontal plane. We compute the statistical properties of the firing rates of...
employees or consultants, provided access to its proprietary data on de-identified hospital patients. Competing Interests: Manu N. Capoor, John C. Baird, and Fahad S. Ahmed are paid employees of MMF Systems
Background The relationship between intervertebral disc degeneration and chronic infection by Propionibacterium acnes is controversial with contradictory evidence available in the literature. Previous studies investigating these relationships were under-powered and fraught with methodical differences; moreover, they have not taken into consideration P. acnes’ ability to form...
Do response-related processes affect perceptual processes? Sometimes they may: Algom and Marks (1990) produced different loudness exponents by manipulating stimulus range, and thereby also modified the rules of loudness summation determined by magnitude scaling. The present study manipulated exponents by having a dozen subjects learn prescribed power functions with exponents of 0...
JOHN C. BAIRD 0 1 2 0 This research was sponsored by a grant from the Swedish Environ mental Protection Board to Ulf Berglund and also by a grant from the University of Stockholm. The work was ... conducted while John C. Baird was a visiting professor at the Department of Psychology, University of Stockholm and the Department of Hygiene of the National Institute of Environmental Medicine. We thank
Background In previous studies, Propionibacterium acnes was cultured from intervertebral disc tissue of ~25% of patients undergoing microdiscectomy, suggesting a possible link between chronic bacterial infection and disc degeneration. However, given the prominence of P. acnes as a skin commensal, such analyses often struggled to exclude the alternate possibility that these...
expert advice and encouragement on all phases of this research. We also appreciate the constructive comments of Roberta Klatzky and two anonymous reviewers. Reprint requests should be sent to John C. Baird
dressed to John C. Baird, Department of Psychology , Dartmouth Col lege, Hanover, NH 03755 1 Dartmouth College , Hanover, New Hampshire The size-distance invariance hypothesis (SDIH) was examined for
In a simulated absolute judgment task, subjects guessed which numeral would appear next in a random sequence. Feedback was given after every trial. The average response for the nth trial was analyzed as a joint function of both the response and the feedback for the previous trial. The results confirm those of an earlier study by Ward and Lockhead (1971). Two new models are...
-Packard video equipment. Requests for reprints should be sent to John C. Baird, Department of Psychology, Dartmouth College, Hanover, New Hampshire 03755. for a different purpose by Swets, Green, Getty
An experiment was conducted to explore the quantitative relationship between "goodness" and the amount of symmetry in visual designs. Subjects arranged items in one, two, and three dimensions in an aesthetically pleasing manner. Each design was analyzed to determine its amount of symmetry, and the percent of subjects who created designs having each possible degree of asymmetry...
A quantitative description offrontal-size judgments is presented in three models. The models are similarin that each is based upon the power function between theoretical and judgment ratios. Within broad limits, the exponent of the function indicates the specific experimental conditions. The Null model describes judgments when stimulus cues are totally reduced, and the visual...
A psychophysical approach was used to evaluate the results of reducing the number of stimuli in the visual field upon distance estimates. It was expected that decreases in numerosity would be accompanied by decreases in the magnitude of distance estimates. Numerosity reduction did have a slight but significant effect in the expected direction.
This study evaluated the result of a reduction in the number of types of stimuli (heterogeneity) in the visual field upon distance estimates. Heterogeneity reduction led to significantly shorter distance estimates when a standard consisted of unequal numbers of stimulus-types, but not when they were equally represented.
given by Virgil Graf and W. L. Gulick on the arrangement of the optical and sound equipment used in this study. Requests for reprints should be sent to John C. Baird, Department of Psychology, Dartmouth
This paper describes the results of three experiments on the global precedence effect, using stimuli derived from the receptive field characteristics of neurons in the visual cortex. Thus, the local cue consists of oriented line segments whose sizes correspond to the average size of the central portion of receptive fields in parafoveal representations of the macaque primary...
Behavioral modeling of voice intensity was demonstrated under several conditions. Four groups of Ss first read a list of words aloud, then listened to a list of words, and finally read a third list of words aloud. The sound intensity of the second list was high (115 dB)for two groups and low (20 dB)for two groups. Within an intensity level, one group wore earplugs during the...
Psychophysical theories differ in the relative weight given to sensory and cogruuve variables. Two opposing theories are described and tested in an experiment designed to vary a cognitive factor while maintaining a constant sensory factor. The method of magnitude estimation was used with the constant stimulus attribute of line length. The cognitive factor was varied by providing...
