Olfactory adaptation and recovery in old age

Four experiments are reported in which it is shown that elderly adults are more prone than young adults to olfactory adaptation and are slower to recover threshold sensitivity. The first three experiments differed in detail, but had in common an initial threshold determination for 1-butanol, a 30 s exposure to a concentration twenty-seven times threshold, followed by repeated presentation of the initial threshold level at various intervals after adaptation. In three experiments accuracy of forced-choice discrimination was poor immediately after adaptation but tended to improve with time, and considerably faster in the young than in the elderly. In the fourth experiment, groups of twenty-three elderly and twenty-five young subjects threshold-matched for pyridine were compared. The subjects participated in three sessions in which pyridine was infused into a test chamber at either 2.5, 1.25, or 0 L min-1 (sham session). At 2.5 L min-1 both groups were able to track the buildup of odor intensity during infusion and its decline after infusion. In contrast, at 1.25 L min-1 only the young were able to track odor intensity, even though the concentration rose above initial threshold levels.     

Femininity and work plans protect women against postpartum dysphoria

This study examined contributions of the following variables to postpartum depressive symptomatology: level of antepartum depression, loss of social reinforcement, assertiveness, sex-role orientation, and work plans. The Beck Depression Inventory (BDI), Pleasant Events Schedule (PES), Assertion Inventory, and Bem Sex Role Inventory (BSRI) were administered to 69 women during the eighth month of pregnancy. One month after delivery, subjects were administered the PES, postdelivery questionnaire, and BDI. A hierarchical regression analysis revealed that antepartum BDI scores predicted postpartum depressive symptomatology, and BSRI Femininity scores and work plans were significant negative predictors. A one-way analysis of variance of sex role orientation on postpartum BDI scores showed that undifferentiated women reported more depression than other sex role groups.     

Order of Presentation and Verbal Recruitment Strategy Effectiveness1

This study examined the relative effectiveness of three different verbal recruitment strategies (opinion conformity, other enhancement, and self-enhancement) presented in different orders. Sixty undergraduates viewed three recruiters, each of whom used a different recruitment strategy to describe a hypothetical graduate program. Participants rated their impressions of each recruiter and then decided which program to attend. Results indicated that presentation order significantly affected participants' ratings of the opinion conforming and self-enhancing recruiters. Furthermore, although participants generally preferred the other enhancing and opinion conforming recruiters, this preference did not translate into a decision to attend the other enhancer's university. Implications for both the recruitment and impression management literatures are discussed.     

Modifying acute pain by matching cognitive style with cognitive treatment

To test whether congruence between cognitive style and cognitive coping would facilitate the attenuation of pressure pain, 30 verbalizers and 30 visualizers were assigned in equal numbers (ns = 10) to pleasant imagery, rational thoughts, and expectancy conditions. Separate 2 X 3 (cognitive style X experimental condition) analyses of covariance on pain tolerance and subjective discomfort indicated that imagery was superior to expectancy in raising tolerance. These findings are discussed in terms of the flexibility of cognitive coping and the content of the images and thoughts which were used.     

Temporal summation related to the nature of the proximal stimulus for the warmth sense

Magnitude estimations of the warmth aroused by radiant stimulation of the forehead showed that warmth obeys the psychophysical power law when the’ duration of the stimulus is relatively long (3 or 6 sec). When duration is short (0.25, 0.5. or 1 sec), however, warmth grows as a more complex function of irradiation. The family of psychophysical functions measured for the various durations can be used to generate the rules by which radiant intensity and duration trade to preserve constant warmth. These rules vary systematically from complete temporal summation (i.e., complete reciprocity) near threshold to less and less complete summation as warmth level increases. When, however, the stimulus is expressed as an equivalent change of temperature in the skin, there is no summation, only adaptation. It can be shown that temporal summation observed psychophysically must result from the heat-transfer properties of skin tissue.     

The form of the psychophysical function near threshold

Psychophysical functions typically depart from a simple power law in the vicinity of the absolute threshold. Five versions of the psychophysical power law have been proposed to describe the function near threshold. An account is given of some of the difficulties encountered in attempts to decide among the various versions by means of empirical tests.     

Brightness function: Role of the pupil

Pairs of brightness functions were generated by magnitude estimation, one pair for each of three flash durations (0.5,1.0, and 3.0 sec). Each pair comprised a function obtained with an artificial pupil and a function obtained with the uncontrolled natural pupil. The pupil turned out to have little or no effect on the form and slope of the power functions for brightness, even when flash duration was as long as 3.0 sec.     

Individual brightness functions

A total of 34 individual brightness functions were measured for 18 observers by two different methods. In one method the observer set various luminance levels of a white target and assigned numbers proportional to the apparent brightness of the levels set. In the other method the observer adjusted the loudness of a white noise and the luminance of a white target in order to achieve a series of cross-modality matches between loudness and brightness. Both methods gave good approximations to power functions, showing that the psychophysical power law holds for the individual perceiver.