Odor intensity and pleasantness for a diverse set of odorants

Data Analysis Office, U.S. Army Natick Laboratories, Natick, Massachusetts 01760 Observers compared the odor of butanol to the odors of various concentrations of 32 chemicals, and also rated the odor pleasantness and unpleasantness of these 32 odorants by a line matching procedure. All stimuli were presented to the observers by air dilution olfactometers. Odor intensity matches between each odorant and butanol were often describable by power functions. A derived magnitude estimate of odor intensity was obtained through a calibration of the butanol concentration scale. Most odorants grew less rapidly in intensity than butanol, and all odorants grew in intensity as decelerating functions of concentration. A more general function of the form P =: k₁ + k₂C^k3 was needed to account for the pleasantness-unpleasantness judgments. In this study, most odorants were rated either neutral or unpleasant. Observers showed far more variability in hedonic judgments than in intensity judgments.     

The effect of familiarity on the processing of fragmented figures

The processing of fragmented figures was investigated in a same-different reaction time task with pairs of intact and pairs of fragmented alphabet letters. The effect of fragmentation was significantly larger for pairs of letters rotated into an unfamiliar orientation than for pairs of normally oriented letters. Since this significant interaction was obtained for subjects emphasizing a structural mode of processing (Hock, 1973), it was concluded that familiarity had a direct effect on the structural/ organizational processing of the fragmented figures.     

The case records of the Psychological Clinic at the University of Pennsylvania (1896-1961).

The case records of the Psychological Clinic of the University of Pennsylvania the first established in this country, have been transferred to microfilm to save them from desctruction. A survey of the records indicate that they may be valuable in both historical and follow-up research. The microfilms can be made available to qualified investigators with worthy projects.     

The anomaly of anomaly

In order to determine whether mechanically generated sentences, often referred to in the literature as anomalous, are in fact anomalous, subjects in the present experiment were asked to do two different tasks: a paired-associates learning task involving anomalous sentences as responses, and a second task in which they were asked to interpret such sentences. These tasks were counterbalanced across different groups of subjects. Results of the interpretation task showed that a large proportion of subjects were able to give interpretations for anomalous sentences, while learning results indicated that anomalous sentences were more difficult to anticipate than natural sentencesonly when task order was Learn first, Interpret second. In the order Interpret-Learn, differences in ease of learning between anomalous and naturally occurring sentences did not appear. The results of this study demonstrate that anomalous sentences are interpretable, that a range of difficulty for such sentences can be established, that anomalous sentences are learned as easily as naturally occurring ones after interpretation, and that many of the interpretations given to such sentences are metaphoric in character. These findings are discussed in terms of their implications for models of lexical organization.     

On the locus of visual dominance

A series of six experiments explored the dominance of vision over audition reported by Colavita (1974). We first confirmed the existence of visual dominance in a paradigm somewhat different from Colavita’s: Mean reaction time (RT) to a light was found to be faster than to a simultaneously presented tone, even though the stimuli were equated in subjective intensity and even though RT to the tone presented alone was faster than to the light presented alone. Additional experiments showed that when subjects did not have to respond to light, tone RT was equal or faster (intersensory facilitation) when a light was present than when it was not. These findings suggest that sensory or perceptual processing of the tone is not affected by the light, i.e., that visual dominance is nonsensory in locus and depends on the relevance of the light stimulus. This interpretation was reinforced by other findings which showed that the degree of visual dominance was sensitive to the probability of light, tone, and light-plus-tone trials and to instructions to attend to a specific modality, but was not sensitive to the intensity of the light.     

Overt activity during conditioned suppression: a search for punishment artifacts

Pigeons, previously trained to peck a key (using food as the reinforcer), were permitted unlimited access to food and, concurrently, key pecking was allowed to go unreinforced until all pecking ceased. A tone ending with electrical shock was then repeatedly presented in an effort to establish the tone as a potentially suppressing stimulus. When key pecking was later reestablished, tone presentation (without shock) sharply reduced the rate of pecks. At selected points throughout the experiment, special observation procedures supplemented the recordings of key pecks and provided detailed fine-grain protocols of the birds' overt movements during the periods before, during, and after tone presentations. Results indicated that neither punishment of key pecks nor punishment of other overt movements was a necessary precursor to the conditioned suppression observed in the final stage. As such, the findings support interpretations of conditioned suppression that characterize the phenomenon as reflecting a conditioned emotional reaction that either directly or indirectly inhibits overt activity.     

Laterality effects in perceptual matching

Two experiments are reported in which Ss had to indicate whether pairs of simple geometric forms were “same” or “different.” In Experiment I the two forms were either both in the left visual hemifield or both in the right hemifield. Reaction times were unaffected by the locus of the stimuli. In Experiment 2, in addition to left and right pairs, there were pairs in which one of the stimuli was on the left and the other was on the right. Under these conditions, reaction times were faster for pairs totally on the left than for pairs totally on the right. The data support the notion that implicit scanning patterns are important in determining laterality differences. When such scanning is not involved and when simple nonverbal stimuli and responses are employed, laterality differences are eliminated.     

Intensity scales for pure tastes and for taste mixtures

In four series of studies, taste intensities of sour, bitter, sweet, and salt were measured by number matching (magnitude estimation), and by noise matching. The two procedures agreed in their estimates of the power-function exponent for each taste. Representative exponents obtained from the studies are 1.0 to 1.1 for sour and bitter and 1.3 to 1.5 for sweet and salt. In a second set of studies each taste was judged against three or more background levels of a second taste. The results suggest that the power-function exponent is unaffected when a second taste is present in the solution. Whether the intercept changes in taste mixtures was not determined in these experiments.