Stimulus sequence and the exponent of the power function for loudness

In two experiments, 15 and 13 subjects estimated the loudness of 12 sound-pressure levels (38-104 dB; 6-dB intervals) of a 1000-Hz tone by the method of magnitude estimation with a modulus assigned to the first stimulus presented. The tone duration was 1 sec. and the interstimulus interval was 6 sec. The presentation order was systematically ascending-descending in one experiment and balanced-irregular in the other. The results indicate that (1) loudness is a power function of sound pressure with an exponent of 0.60 for the systematic order and 0.29 for the irregular order. (2) For both the irregular and systematic orders, a large step-size (12 or 18 dB) between the stimulus on Trial n and on Trial n-1 (or n-3) results in a slight assimilation effect. This also occurs for the small step-size (6 dB) in the irregular order. (3) The size of momentary exponents (based on two points, Trials n and n-1 or n-3) depends on the sound pressures of successive stimuli, whether the steps are positive or negative, and whether the stimuli have been presented in systematic or irregular order. For positive steps, the momentary exponent is lower for a soft tone (Trial n) than for a loud tone, whereas for negative steps the momentary exponent is lower for a loud tone than for a soft tone. These effects ar more pronounced when these stimuli are presented in an irregular order. A relative judgment model is offered for magnitude estimation. It assumes that subjects judge the loudness of a stimulus in terms of three reference markers: the minimum and maximum sound pressures as well as the sound pressure of the previous stimulus.     

Effects of stimulus duration and ISI on accuracy and transference errors in pictorial recognition

The influence of stimulus duration and ISI on accuracy of recognition for two-part configurations was investigated in two experiments. A six-alternative forced-hoice recognition procedure is described that tested (1) subjects’ ability to recognize correct or partially correct stimuli, and (2) their tendencies to make transference errors. Subjects were significantly more accurate in recognition of pictorial components when given a longer (2-sec) rather than a shorter (.5-sec) exposure to stimuli, with ISI held constant (.5 sec). There was no beneficial effect on recognition of pictorial components when ISI was lengthened from .5 to 2 sec Iwith a .5-sec stimulus duration) or from .5 to 1.5 to 7 sec Iwith a 2-sec stimulus duration). The total time hypothesis received no support, since when two groups were given the same total time (2.5 sec for stimulus duration plus ISI), the group given the longer 12-sec) stimulus duration was significantly more accurate in partial recognition than a group given a longer 12-sec) ISI. There was a high incidence of transference errors in all experimental groups, although subjects’ ability to distinguish old stimuli from distractors made by recombining parts from different targets was not affected by any of the temporal manipulations. It appeared that, although length of stimulus duration determines the number of components encoded from a picture, the encoding of information that integrates these components into a whole does not require additional processing time.     

The mediation of aggressive behavior: arousal level versus anger and cognitive labeling.

The principal goal of the present research was to contrast the arousal-level and cognitive-labeling (anger) interpretations of aggressive behavior. In a 2 X 5 factorial between-subjects design, subjects were first either insulated or treated neutrally by a confederate. Four fifths of the subjects then received on each of 50 trials a 10-sec tone sequence while deciding whether or not to give an "electric shock" to the confederate. The stimulation was either simple (4.00 bits/tone) or complex (9.17 bits/tone) and was presented at either a comfortable (73-d.) or an aversively loud (97-db.) level. A group was assigned to each of the four stimulation treatments. The remaining subjects received no stimulation. In terms of the total number of shocks administered by subjects in different groups, the cognitive-labeling hypothesis was strongly supported. Both complexity and loudness had an effect, but only on insulted subjects. Other implications of the results were discussed.     

Avoidance responding as a function of stimulus duration and relation to free shock

Response-independent pairings of a tone and a brief shock were superimposed on uncued avoidance responding in four groups of rhesus monkeys. For one group, tone presentations were immediately followed by an unavoidable electric shock; for the remaining groups, gaps of 5, 20, and 80 sec intervened between tone termination and shock delivery. These temporal values subsume paradigms usually treated as discrete procedures; the conditioned emotional response procedure (0-sec gap between tone and shock), trace procedure (5-sec gap) and safety-signal training (80-sec gap). Within each group, tone durations of 10, 20, 40, and 80 sec were examined. A response pattern marked by maximum response rate in the initial 5 sec of the tone followed by deceleration before shock was observed when shock immediately followed the tone, but not when gaps were interposed between the tone and shock. Response rates in the first 5 sec of the tone were a function of both tone duration and duration of the gap. When the gap was 0 to 5 sec, initial response rates were highest in longer duration tones; this relationship between tone duration and initial tone response rate was not observed for longer gaps.     

Serial position curves in spatial memory of rats: Primacy and recency effects

Memory for lists of items was tested in rats (N = 18) in an 8-arm radial maze. In Experiment 1 trials consisted of a study phase, in which the rat could freely choose five arms to obtain a food reward, and a test phase in which the animal was presented with a choice between a novel and a previously visited arm. The rat received additional food reinforcement only when visiting the novel arm. The two phases of a trial were separated by a retention interval of 30 sec or of 4, 16 or 60 min. It was found that recall of the five free arm choices was related to the serial position of the previously visited arm. There was a significant recency effect at the 30-sec delay. With longer retention intervals this disappeared, and a significant primacy effect could be observed. In Experiment 2 the same animals were given forced arm entries during the study phase and delays of 30 sec or 4 or 16 min before the test phase. Again, there was a trend towards a recency effect after the shorter delays and a significant primacy effect after the 16-min interval. These results show that, in the recall of lists of spatial items, rats have serial position curves with primacy and recency effects, depending on the length of the retention interval.     

Reevaluating the role of the medial prefrontal cortex in delay eyeblink conditioning

It has been proposed that the medial prefrontal cortex (mPFC) is not necessary for delay eyeblink conditioning (DEC). Here, we investigated the involvement of the mPFC in DEC with a soft or loud tone as the conditioned stimulus (CS) by using electrolytic lesions or muscimol inactivation of guinea pig mPFC. Interestingly, when a soft tone was used as a CS, electrolytic lesions of the mPFC significantly retarded acquisition of the conditioned response (CR), and muscimol infusions into mPFC distinctly inhibited the acquisition and expression of CR, but had no significant effect on consolidation of well-learned CR. In contrast, both electrolytic lesions and muscimol inactivation of mPFC produced no significant deficits in the CR when a loud tone was used as the CS, or in the unconditioned response (UR) when a soft or loud tone was used as the CS. These results demonstrate that the mPFC is essential for the DEC with the soft tone CS but not for the DEC with the loud tone CS.     

Rats' Memory for Serially Presented Novel Flavours: Evidence for Non-spatial Primacy Effects

Four experiments examined the effects of serially presenting a number of novel flavours to rats on their subsequent consumption of those flavours. In Experiments 1-4, rats were orally infused with 0.5 ml of flavour over 30 sec for each of five flavours in the exposure phase of the experiment. In these studies, primacy and recency effects emerged, the size of the primacy effect being related to the length of the retention interval, which varied from zero to twenty-four hours. Thus, both primacy and recency effects can be generated using nonspatial stimuli with rats.     

Selective changes of sensitivity after adaptation to simple geometrical figures

Using simple geometrical figures, the effect of adaptation upon sensitivity to figures of the same or different form was investigated. The adapting stimuli (blank white field, contour triangles, or circles) were presented for 1, 5, 30, or 60 sec. The test stimuli were always triangles, presented for a short exposure time at .1, .2, .4, .8, and 1.2 sec after the offset of the adapting pattern. The threshold duration of the test stimuli was measured. It was found that both adapting patterns raised the threshold above that measured for adaptation with the blank white field. But it wss only for the pair “adapting triangles-test triangles” that an increase of the time of adaptation beyond 5 sec resulted in an increase of this effect. This suggests that selective lowering in sensitivity during prolonged viewing of some figures may develop. The effect disappeared after about 1.2 sec following an exponential curve.     

Attention orienting by eye gaze and arrows reveals flexibility to environmental changes

This study aimed to evaluate the difference in non-predictive cues between gaze and arrows in attention orienting. Attention orienting was investigated with gaze or arrows as separate cues in a simple condition (i.e., block design) in Experiment 1 and in an unpredictable condition (i.e., randomized design) in Experiment 2. Two kinds of sound (voice and tone) stimuli were used as targets. Results showed that gaze and arrow cues induced enhanced attention orienting to a voice versus tone target in the block condition. However, in the randomized condition, enhanced attention orienting to a voice versus tone target was found in gaze but not arrow cues. The congruency of the meaning between a social cue (i.e., gaze) and a social target (i.e., voice) was clear in the randomized but not blocked design, because social gaze and non-social arrow cues were implemented in the same block. Thus, attention orienting might be mediated by the associated relationship of cue–target in a randomized condition, as an enhanced orienting effect was found when the associated relationship of cue–target was strong (i.e., social cue and target). The present study suggests that the difference in attention orienting between gaze and arrows is apparent in a randomized design (the unpredictable condition), and people employ a flexibly strategy of orienting to better respond to environmental changes.     

One-trial cardiac conditioning in dogs

Our interest in cardiovascular conditioning, particularly the fact that conditional tachycardia has been observed in many dogs after only one or two combinations of conditional and unconditional stimuli, led us to investigate conditioning using a single application of an unconditional stimulus. Initially we studied the effect of orienting stimuli (soft tones) on the heart rate in 9 dogs. After 30–100 presentations of the tones alone, each dog received on one occasion a 25-volt shock (sufficient to cause yelping and struggling) to a leg as unconditional stimulus immediately following a tone. Thereafter 30–100 additional tones were presented with no further shock. Little or no heart rate change occurred during the orienting tones (before shock). Three types of cardiac changes occurred during experimental sessions after the shock: 1) Increased heart rate during the tones in 5 dogs; 2) Generalized lowering of heart rate during all experimental sessions after shock in 4 dogs; 3) Electrocardiographic changes during tones in 3 of the dogs also showing the generalized decrease in heart rate. No motor flexion conditional reflexes developed. Tones an octave different in pitch from the one associated with the shock also caused approximately the same heart rate changes, indicating lack of differentiation. This one-trial cardiac conditioning persisted after the single conditioning trial for more than a month in 2 dogs and for at least 3 to 5 sessions in the other dogs.     

Factors producing and factors not producing time errors: An experiment with loudness comparisons

Pairs of 1-sec, 1,000-Hz tones, with interstimulus intervals of 1.5 sec, were judged by 60 subjects in categories of “louder,” “softer,” and “equal.” The judgments referred to the first tone in the pair for half of the subjects and to the second tone for the other half. Perceived loudness differences were scaled by a Thurstonian method. The SPL of the standard tone alternated between 50 and 70 dB in one experimental series and between 30 and 50 dB in the other. Time errors (TEs) were consistently positive (first tone overestimated relative to second) at the lower SPL and negative at the higher SPL. This “classical” effect of stimulus level on TE was thus shown to depend upon the relative, rather than the absolute, level of stimulation. The judgment mode was of very little consequence, which strongly contradicts TE theories that emphasize response-bias effects. The quantitative results are interpreted in terms of a general successive-comparison model employing the concepts of adaptation and differential weighting of sensation magnitudes.     

Effects of massed versus distributed practice on gross and fine motor proficiency of educable mentally handicapped adolescents

Gross and fine motor proficiency were studied in a sample of 52 educable mentally handicapped students (M = 15.8 yr.), half of whom were assigned to 15 30-sec. trials, a relatively massed practice schedule with 5 sec. between trials, and half to a distributed practice schedule with 30-sec. rests. 5 trials were given 24 hr. later. All subjects performed the stabilometer balance task to measure gross motor proficiency and a 45-rpm pursuit rotor task to measure fine motor proficiency. No significant differences with regard to the practice schedule used early in learning were found, however, boys scored significantly higher on the pursuit rotor than girls.     

Punishment of observing by a stimulus associated with the lower of two reinforcement frequencies

Three pigeons were used to investigate the effects of a stimulus associated with the lower of two reinforcement frequencies on the response producing it. In a three-key chamber, pecking the center key produced grain on alternating variable-interval schedules with mean durations of 2 min or 30 sec. Initially, green illumination of the keys accompanied the more favorable (30-sec) schedule and red accompanied the less favorable (2-min) schedule. Then the keys remained yellow unless the bird pecked one of the side (observing) keys to produce the discriminative stimuli for a 30-sec period. Subsequently, when red was withheld as a possible consequence of pecking a particular side key, the rate on that key increased; when red was restored, the observing rate decreased. Thus the stimulus associated with less frequent reinforcement had a punishing effect on the behavior producing it. When green was withheld on one of the side keys and the other key produced both colors, observing behavior was not maintained on the red-only key, but was maintained on the key that produced both colors.     

Effects of stimulus duration on observing behavior maintained by differential reinforcement magnitude

Pigeons made observing responses for stimuli signalling the availability of either 10-sec or 2-sec access to grain on fixed-interval 1-min schedules. If observing responses did not occur, food-producing responses occurred to a stimulus common to both reinforcement magnitudes. When the stimuli remained on for the duration of the components and signalled differential reinforcement magnitudes, observing responses were maintained; however, when the stimuli remained on for 10 sec, observing responses decreased markedly. In addition, it was shown that the occasional presentation of the stimulus signalling 10-sec access to grain was necessary for the maintenance of observing behavior. A control condition demonstrated that when all the available stimuli signalled 6-sec access to grain, observing responses declined. Taken together, the results demonstrated that the occasional presentation of the stimulus that remained on for the duration of the component and signalled the larger reinforcement magnitude was necessary for the maintenance of observing behavior.     

Effect of information feedback on temporal discrimination in concurrent and post-feedback measures

College students estimated time intervals (5, 6, 7, 8, and 9 sec.) where one group (N = 20) received information feedback in terms of actual interval durations and a second group (N = 18) received no information. Theshold measures were then taken for all subjects using the method of constant stimuli (comparison stimuli of 5, 6, 7, 8, and 9 sec. and a 7-sec. standard). In addition to increased accuracy and consistency of judgments, the feedback group showed a decreasing Weber fraction during the estimation phase, while the Weber fraction for the no-feedback group increased. The feedback group retained only a slight advantage in subsequent threshold measures; group differences in difference thresholds and derived nonparametric estimates of d' were nonsignificant.     

时间判断的视听通道效应的实验研究

该实验用视觉或听觉两种方式一次呈现两个时距,随机地指定其中的一个时距要求被试立即再现或延迟5秒再现。实验结果表明:①对短时距信息(1秒,1.5秒,2秒)的判断,听觉比视觉具有明显的优势,听觉的再现时距较精确,延迟对听觉的时间信息检测的破坏作用较小;而对长时距信息(10秒,11秒,12秒)的判断,却未发现听觉比视觉有优势现象。②通道效应的产生机制源于记忆的特点而不是感觉储存的特点。③对短时距的判断通常表现为正时间顺序误差,而对长时距的判断则表现为负时间顺序误差。     

Psychological and psychophysiological effects of music intensity and lyrics on simulated urban driving

The main aim of this study was to investigate the effect of musical characteristics (i.e., presence of lyrics and loudness) in the context of simulated urban driving. Previous work has seldom isolated musical characteristics and examined these both singularly and interactively. We investigated the potentially distracting effects of processing lyrics through exposing young drivers to the same piece of music with/without lyrics and at different sound intensities (60 dBA [soft] and 75 dBA [loud]) using a counterbalanced, within-subjects design (N = 34; M_age = 22.2 years, SD = 2.0 years). Six simulator conditions were included that comprised low-intensity music with/without lyrics, high-intensity music with/without lyrics, plus two controls – ambient in-car noise and spoken lyrics. Between-subjects variables of driving style (defensive vs. assertive) and sex (women vs. men) were explored. A key finding was that the no lyrics/soft condition yielded lower affective arousal scores when compared to the other music conditions. There was no main effect of condition for HRV data (SDNN and RMSSD). Exploratory analyses showed that, for assertive drivers, NASA-TLX Performance scores were lower in the no lyrics/soft condition compared to the lyrics/loud condition. Moreover, women exhibited higher mean heart rate than men in the presence of lyrics. Although some differences emerged in subjective outcomes, these were not replicated in HRV, which was used as an objective index of emotionality. Drivers should consider the use of soft, non-lyrical music to optimise their affective state during urban driving.     

Signal recognition as influenced by presentation schedules

Performance in a recognition task involving two amplitudes of the same tone was investigaled over a wide range of presentation schedules. The task was arranged so that there was no trial-to-trial feedback or other information regarding the relative frequencies of the two tones. The hit and false alarm rates (the proportion of “loud” responses to loud and soft stimuli, respectively) on any given trial were strongly influenced by the stimulus and response on the preceding trial. In general, Ss tended to repeat the last response and were more accurate after a stimulus alternation than after a stimulus repetition. In addition, hit and false alarm rates were inversely related to the presentation probability of the loud tone, in contrast to the direct relation typically found in signal detection experiments and in recognition experiments with trial-to-trial feedback. A mathematical model incorporating three processes (memory, comparison, and decision) was shown to give a good account of these data.     

Magnitude estimations of the course of gustatory adaptation

Magnitude estimations of 15-sec intervals were obtained during 2-min and 5-min adaptation of suprathreshold solutions of NaCl. quinine sulfate (QSO₄, and sucrose. Expectorating and adding fresh adapting solution at the end ofeach minute produced higher estimations than those obtained with continuous adaptation because of salivary dilution. Separation of the adaptation determinations by 45-sec rest intervals rather than 5 min had no effect on the form or magnitude of the functions for NaCl or sucrose, although QSO₄. adaptations separated by the shorter rest intervals were of greater magnitude. The absence of complete adaptation was largely attributed to the effects of tongue movements.     

Auditory streaming: Competition among alternative organizations

It has been suggested that the ON and OFF components of the auditory evoked potential (AEP) may be mediated by independent physiological mechanisms and that the response to a brief tone consists of overlapping ON and OFF responses. Two experiments were performed to evaluate these proposals. First, AEPs were recorded to tonebursts of various durations presented at a fixed rate. As the tonebursts were made longer, they evoked smaller ON responses and larger OFF responses, particularly when either response followed the other by less than 5 sec. This indicates that ON and OFF responses are not physiologically independent. Second, the AEP to a 25-msec tone was compared with the ON response to a 2,000-msec tone. At an interstimulus interval of 4 sec, the difference wave formed by subtracting the latter AEP from the former contained clear N₁ (ca. 100 msec) and P₂ (ca. 180 msec) components, which have been interpreted as an OFF response by some authors. These components in the difference wave were greatly reduced or even inverted at 10-sec interstimulus intervals, however, where interactions between ON and OFF responses to successive stimuli were minimized. This result indicates that any residual OFF response in the AEP to a brief tone is very small in amplitude, if present at all.