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.     

Apparent warmth as a function of thermal irradiation

The skin of the back was periodically exposed to a source of radiant heat. In Experiment 1, 20 Ss matched numbers to the apparent warmth aroused by various levels of irradiant flux (method of magnitude estimation). In Experiment 2, 15 Ss matched the loudness of a white noise to the apparent uwmth aroused by the same levels used in Experiment I (method of cross-modality matching). Both experiments showed that apparent warmth is related to absorbed irradiance by a power function whose exponent is approximately 0.7.     

Spatial summation and the dynamics of warmth sensation

Various areal extents of the forehead and back were thermally irradiated at various levels of intensity. For any areal extent, the degree of apparent warmth grows approximately as a power function of intensity level; the larger the area, the smaller the exponent of the power function. Two families of psychophysical functions, one for the forehead, the other for the back, both show that the power functions extrapolate to a point of convergence in the neighborhood of the threshold for pain and tissue impairment. The rules that govern spatial summation of warmth reveal themselvesin the two families. Intensity and area trade one for the other to preserve the same level of warmth. At faint sensation levels, reciprocity is the rule of trading; but with increasing sensation level, area makes a weaker and weaker relative contribution to warmth, and, as a result, it takes a larger and larger percentage change in area to offset a given percentage change in intensity.     

Effort in isometric muscular contractions related to force level and duration

The degree of perceived force involved in squeezing a handgrip dynamometer is shown to grow as a power function of the force of isometric contraction and also as a power function of the duration of the squeeze. The exponent for force turns out to be more than twice that for duration. These two power functions are able to predict measurements of muscle endurance, i.e., of the maximum length of time that contraction of any constant level of force can be sustained.     

The relationship between parenting styles and young adults' self-concepts and evaluations of parents.

In the present study, 123 college students were surveyed in order to assess their self-concepts, evaluations of parents, and perceptions of their parents' parenting styles. Notably, the students' self-concepts were found to vary directly with perceived level of parental warmth, but did not vary as a function of their parents' level of restrictiveness. Fathers and mothers were found to be rated more highly if they were perceived as being warm and permissive rather than hostile and restrictive. Finally, opposite-sex parents' level of warmth also correlated with how each parent was evaluated. Some explanations for these findings are offered.     

Resources versus respect: Social judgments based on targets' power and status positions

In two experiments, we investigate how individuals' levels of power and status interact to determine how they are perceived by others. We find that power and status have similar, positive, effects on judged dominance. We also find that power has a negative effect on perceived warmth, but status moderates this “power penalty”: high power without status is associated with low warmth, but power with status is judged warm. Consequently, we find high status individuals, regardless of power level, are perceived positively - dominant and warm - whereas high power-low status individuals are judged most negatively — dominant and cold (Experiments 1 and 2). As a result, perceivers expect positive interactions with high status individuals, but negative interactions with high power, low status individuals (Experiment 2). These findings provide insight into power and status social judgments, and further our understanding of similarities and differences between these distinct, yet related, constructs.     

Flooding as a function of shock level and length of confinement

In a one-way avoidance learning situation with rats, response prevention trials facilitated extinction as an increasing function of the duration of the prevention interval for shock levels below 1.8 mA. For 1.8 mA, extinction was a nonmonotonic function of the response prevention interval, with 15- and 210-sec durations showing the most facilitation of extinction. For all response prevention intervals except 15 sec, trials to extinction was a direct function of shock level. For 15 sec, it was an inverse function of shock level. The unexpected interaction of shock level with prevention interval was explained by invoking the concept of relief.     

Brightness exponent as a function of flash duration and retinal eccentricity

The effect of flash duration on the exponent of the brightness power function was investigated in the fovea and 20-deg periphery using a method of direct magnitude estimation. The flash duration employed covered a 5-log-unit range between .001 and 100 sec. The results showed that the exponent is clearly time-dependent for both extremes of the duration—that is, very short (.001 to .1 sec) and prolonged (3 to 100 sec) durations—but not for the medium flash durations between .1 and 3 sec. Furthermore, the exponent is a little larger for peripheral viewing than for foveal viewing except for the durations below approximately .03 sec. The systematic change of the exponent as a function of duration is discussed in terms of retinal and postretinal intensity coding functions.     

The duration and perceived intensity of sucrose taste

Thirty-two subjects judged the perceived intensity of each of four concentrations of sucrose over 2 min. Stimuli were either sipped and expectorated or flowed over the subject’s extended tongue. Ratio judgments on a line scale and category ratings were made. Sixteen of the subjects had had extensive training in judging the sensory attributes of food products, and another group of 16 subjects were untrained. The perceived intensity of sucrose rose to a peak within 5 or 10 sec, and then declined over 2 min. In both the sip and the flow conditions, the taste disappeared completely for 26 of 32 subjects. Stronger concentrations were perceived as having greater peak intensities and longer lasting taste. The differences between concentrations were enhanced when sipped rather than flowed over the tongue. Judgments of intensity and duration were largely unaffected by the training level of subjects and the use of different rating scales.     

The temporal course of the relationship between retinal disparity and the equidistance tendency in the determination of perceived depth

Changes in perceived depth as a function of exposure duration were compared for two stimulus conditions. In one. a depth interval between two points of light was produced by the retinal disparity cue, and in the other condition, otherwise identical to the first, the light points were connected by a thin luminous line. The principle finding was that the perceived depth interval between the light points increased as a function of exposure durations greater than 1 sec, while no change in the perceived depth interval between the end points of the line occurred. The results were interpreted in terms of a greater equidistance tendency (ET) operating for the line than for the point condition. It was concluded that both the ET and the retinal disparity cue increase in strength as a function of exposure duration.     

Temporal summation at the warmth threshold

Threshold levels for warmth aroused by infrared irradiation were measured in sLx Ss at durations between 0.05 and 10 sec. Beyond a critical duration of about a second, the threshold does not depend on duration. Below critical duration time t trades for irradiance ? by the formula ? = kt^?0.82. That these properties do not depend much on areal extent of stimulation was demonstrated by a study that compared temporal summation for two different areas of the same S’s skin. Individual differences in apparent absolute sensitivity were explored under the rubric of the theory of signal detection.     

社会层级的内隐刻板印象：权力与地位的不同作用

采用探测词再认范式,考察社会层级的内隐刻板印象。结果发现,在能力推理上,无论地位高低,个体对高权力推理为积极的反应时显著长于消极,对低权力推理为消极的反应时显著长于积极;在热情推理上,无论权力高低,个体对高地位推理为积极的反应时显著长于消极,对低地位推理为消极的反应时显著长于积极。这表明,权力和地位在热情和能力维度的刻板印象中起着不同的作用,其中权力正向预测能力,地位正向预测热情。     

Human responses to various conditions of water temperature

Skin-surface temperatures on thehuman hand were obtained immediately following six exposure times ranging from 5 to 60 sec. for water temperatures varying in 5° increments from 10° to 40°C. The surface of the skin was found to respond rapidly and regularly to both the temperature and time of exposure. In a second study 30 Ss exposed a hand for 5 or 30 sec. to water temperatures ranging from 10° to 45°C. and made ratings on scales of pain and comfort as well as attaching a verbal label (cold, cool, tepid, etc.) to each experience. The experience of cold became more intense over these time intervals while the experience of warmth became less, and with the threshold constant taken into account the sensations of pain and discomfort were found to follow a psychophysical power law. The usefulness of these sorts of data for interpreting the effects of noxious stimuli in basic learning studies is discussed.     

Evocation and characterization of percepts of apparent motion on the face

The percepts evoked by sequential stimulation of sites in close spatial proximity (<2.5 cm) on the face were studied. Both method-of-limits and magnitude-estimation procedures were used to identify and characterize alterations in the percepts produced by systematic changes in the temporal and spatial parameters of the sequence. Each site was stimulated by a vertically oriented row of miniature vibrating probes. Apparent motion was consistently perceived when the delay between the onsets of sequentially activated rows (interstimulus onset interval, or ISOI) fell within a relatively narrow range of values, the lower limit of which approximated 5 msec. Both the upper limit and the perceived smoothness and continuity of the motion percepts (goodness of motion) increased with the duration for which each row stimulated the skin over the range evaluated, 15–185 msec. For the successive activation of only two rows, goodness of motion was not influenced by changes in their separation from 0.4 to 2.5 cm. The ISOI values at which magnitude estimates of goodness of motion were highest increased with the duration for which each row stimulated the skin. As such, maximum goodness of motion decreased with increases in the apparent velocity of motion. When the number of sequentially activated rows was increased from two to four or more, the quality of the motion percepts improved. For the successive activation of multiple closely spaced rows, values of ISOI at which numerical estimates of goodness of motion were highest approximated integral fractions of the duration for which each row stimulated the skin. In this situation, the probes rose and fell in a regular, step-locked rhythm to simulate an edge-like or rectangular object moving across the skin. The goodness of motion so attained was relatively independent of the apparent velocity of motion.     

The influence of affective factors on time perception

Several studies have suggested that both affective valence and arousal affect the perception of time. However, in previous experiments, the two affective dimensions have not been systematically controlled. In this study, standardized photographic slides rated for emotional valence and arousal were projected to two groups of subjects for 2, 4, and 6 sec. One group of subjects estimated the projection duration on an analog scale, whereas the second group of subjects reproduced the intervals by pushing a button. Heart rate and skin conductance responses were also recorded during stimulus presentation as indices of attention and arousal. Time estimation results showed neither a main effect of valence nor a main effect of arousal. A highly significant valence × arousal interaction affected duration judgments. For low-arousal stimuli, the duration of negative slides was judged relatively shorter than the duration of positive slides. For high-arousal stimuli, the duration of negative slides was judged longer than the duration of positive slides. The same interaction pattern was observed across judgment modalities. These results are interpreted in terms of a model of action tendency, in which the level of arousal controls two different motivational mechanisms, one emotional and the other attentional.     

Perceived range, perceived velocity, and perceived duration of the body rotating in the frontal plane

We investigated perceived range, perceived velocity, and perceived duration of the body rotating in the frontal plane (in roll). Specifically, to examine how shear to the otoliths in the inner ears and tactile pressure to the trunk affect judgments of range and velocity, in two experiments, we manipulated rotating range (30°–160°), rotating velocity (1.8°/sec to 9.6°/sec), mean tilt of the body (?60°, 0°, and 60°), and exposure to the visual vertical. Thirty-three normal or blindfolded participants made verbal judgments of range, velocity, and duration for each combination of these factors. The exponents of the power functions fitted to these judgments were, as a first approximation, .94, .61, and .84 for range, velocity, and duration, respectively, and perceived velocity was proportional to the ratio of perceived range to perceived duration (r = .91). These results suggest that the vestibular and somatosensory inputs are effective on judgments of range, but less so on judgments of velocity, and that perceived velocity may be determined as a ratio of perceived range to perceived duration. In addition, we found that (1) when the range the body has traveled is constant, the perceived range increases as the objective velocity decreases (proprioceptive τ effect); (2) self-motion through the tilted roll sometimes enlarges perceived range and perceived duration but reduces perceived velocity; and (3) the exposure to the visual vertical reduces variability of judgments for range and velocity and also reduces perceived range and perceived velocity of self-motion within a small range through the vertical roll.     

The subjective duration of ramped and damped sounds

Two experiments demonstrate that the perceived durations of sounds as long as 1 sec are influenced by the sounds' amplitude envelopes, extending Schlauch, Ries, and DiGiovanni's (2001) observations on sounds of 200-msec duration. Sounds with a monotonic decay (i.e., damped sounds) are heard as substantially shorter than both steady sounds and those with a monotonic increase of level (i.e., ramped sounds). Neither a reaction time (Experiments 1 and 2) nor a staircase (Experiment 2) procedure supported a sensory explanation for these different subjective durations. The results are compatible with the suggestion of Stecker and Hafter (2000) that listeners exclude part of the tails of damped sounds in the computation of their subjective durations.     

Perceived social structural relations and group stereotypes: A test of the Stereotype Content Model in Malaysia

Using data from two studies, the current research tests the Stereotype Content Model (SCM) within a Malaysian context using Chinese and ethnic Malay participants. The aim of the research is to examine the theoretical underpinnings of the SCM in a new context by investigating the role of aspects of the perceived social structure that have not been considered previously. In line with the SCM it is found that the two dimensions of warmth and competence underlie in‐group and out‐group stereotypes in Malaysia. In addition, the in‐group was evaluated more positively than the out‐group on both dimensions. Furthermore, perceived economic social status rather than cultural or power status was related to out‐group competence (Study 1), and to out‐group warmth (Studies 1 and 2). Higher perceived economic competition was weakly and not consistently associated with less out‐group warmth, and political competition was not related to warmth.     

Time,change, and motion: The effects of stimulus movement on temporal perception

The effects of stimulus motion on time perception were examined in five experiments. Subjects judged the durations (6–18 sec) of a series of computer-generated visual displays comprised of varying numbers of simple geometrical forms. In Experiment 1, subjects reproduced the duration of displays consisting of stationary or moving (at 20 cm/sec) stimulus figures. In Experiment 2, subjects reproduced the durations of stimuli that were either stationary, moving slowly (at 10 cm/sec), or moving fast (at 30 cm/sec). In Experiment 3, subjects used the production method to generate specified durations for stationary, slow, and fast displays. In Experiments 4 and 5, subjects reproduced the duration of stimuli that moved at speeds ranging from 0 to 45 cm/sec. Each experiment showed that stimulus motion lengthened perceived time. In general, faster speeds lengthened perceived time to a greater degree than slower speeds. Varying the number of stimuli appearing in the displays had only limited effects on time judgments. Other findings indicated that shorter intervals tended to be overestimated and longer intervals underestimated (Vierordt’s law), an effect which applied to both stationary and moving stimuli. The results support a change model of perceived time, which maintains that intervals associated with more changes are perceived to be longer than intervals with fewer changes.     

Competence and warmth stereotypes prompt mental illness stigma through emotions

Public stigma toward mental illness subgroups (11 mental illness subgroups and 2 subgroups perceived to have mental illness) was examined. Competence and warmth stereotypes were used to predict emotional reactions posited to mediate behavioral inclinations ranging from passive to active harm or facilitation. Fear mediated the relationship between low competence and warmth stereotypes and passive harm. Anger, and to a lesser extent fear, mediated the relationship between low warmth and active harm. Pity mediated the relationship between warmth and active facilitation. Neither envy nor admiration linked stereotypes to behavioral reactions. Results suggest that emotions share motivational direction with behavior, to approach or to avoid, rather than simply sharing valence. Implications for research on stigma toward mental illness subgroups are discussed.