Richard P. Smith

Boredom: A Review

Psychological and psychiatric studies of boredom from 1926 to the present are reviewed. Articles concerning boredom averaged less than one paper per year during the review period. The most consistent finding has been that extroverts apparently constitute a group especially susceptible to this state, although this has not often been tested directly. Stimulus factors such as repetitiousness, lack of novelty, and monotony have been found to generate boredom. Coping strategies have been found to include daydreaming, motor restlessness, exploration, response variability, and withdrawal from the boring situation. Experimental approaches to the problem have generally been traditional. Attempts have consistently been made to relate boredom to altered or characteristic physiological states, but they have not resulted in a consensus concerning these biological variables.

Diurnal variation in response to thermal stimulation: Mouse-hotplate test ☆ ☆☆

Abstract Circadian changes in pain thresholds were assessed in 70-day-old CF1 male mice. The hotplate method was used. A different group of 15 mice was tested every 3 hr over a 48 hr interval. Response latencies were found to vary in a sinusoidal manner over a 24 hr interval. Minimal latencies were obtained 3 hr before the onset of darkness at 1500 hr (4.53 ± 0.26 sec) and maximal latencies at 0300 hr (6.15 ± 0.35 sec). In addition, the pattern of responses varied with time of day. The probability of the jump response was maximal during the dark and minimal during the light period (39% vs 9%). Hind leg flexion exhibited a reciprocal pattern (22% vs 54%). The probability of forepaw licking was not significantly altered during the 24 hr period.

Diurnal variations in the analgesic effectiveness of morphine in mice

Response to thermal stimulation and the analgesic effectiveness of morphine during various phases of the diurnal cycle were assessed by the hotplate method. Saline treated controls exhibited shortest reaction times during the last quarter of the light-phase and first quarter of the dark phase. Longest reaction times were recorded during the last quarter of the dark phase. Doses of 4, 8, 16, and 32 mg/kg of morphine was administered IP at the peak and trough of the pain sensitivity rhythm. The ED50 (95% C.L.) during the last quarter of the light phase was found to be 14.60 (10.6-20.0) mg/kg while during the last quarter of the dark phase the ED50 was found to be 5.85 (4.5-7.7) mg/kg. In a second experiment, independent groups of ten mice each were injected SC with 8 mg/kg of morphine at three hr intervals over a 48 hr test session. Peak analgesic activity was obtained in the group injected during the last quarter of the dark phase while minimal analgesic effectiveness was obtained during the third quarter of the light phase. Central administration of morphine via the intraventricular route yielded the same relationship, i.e., maximal analgesic effectiveness during the last quarter of the dark phase.

EFFECTS OF INDUCED MUSCLE TENSION ON JUDGMENT OF TIME

The functional relation between induced muscle tension and temporal perception was explored. Judgments of the duration of 4 intervals (6, 12, 24, and 48 sec.) were made under 5 levels of muscle tension (0, 10, 20, 30, and 40% of maximum grip strength) by the methods of reproduction and verbal estimation. The effects of degree of muscle tension were negligible at the two shortest stimulus durations. At the two longer intervals, perceived duration decreased as a non-monotonic function of muscle load. Findings were independent of the psychophysical methods employed. Disparities in the magnitude of duration judgments secured by the two psychophysical methods were also dependent upon stimulus duration. At 24 and 48 sec., verbal estimates of the standard interval were significantly longer than reproductions. Differences in response magnitude between methods were not observed at the two shortest stimulus intervals. Results are discussed in terms of the general relation between activity level and temporal perception and in terms of the problem of methodological equivalence in judgments of time.

Effects of temporal uncertainty on watchkeeping performance

Two experiments were conducted to assess the relative effects of signal density and regularity on watchkeeping performance. In Experiment I, three levels of density (6, 24, and 96 signals/hr.) were combined factorially with three levels of variability (coefficients of variation of 0.01, 0.10, and 1.00), and 10 Ss were assigned at random to each of the nine conditions. In Experiment II, five levels of density (6, 12, 24, 48, and 96 signals/hr.) were combined with the same three levels of variability, and 13 Ss were assigned to each condition. Each 5 monitored a visual “blinking-lights” display for an hour under instructions to detect and report the occurrence of certain “critical signals,” i.e., arrests of alternation of the lights. Response times (RT’s) to correctly detected signals in both experiments decreased as a linear function of logarithmic increases in signal density. An uncertainty metric, the signal surprisal due to density, was derived, and the watchkeeper’sRT was expressed as an increasing linear function of this measure of temporal uncertainty. Interpretation of these and other data support a functional, psychophysical approach to the study of watchkeeping behavior.

Attempts to Condition the Acoustic Reflex

Using a delay conditioning paradigm, an attempt was made to condition the acoustic reflex, as produced by a 1000‐cps tone, to onset of a light. Responses were measured in humans with an acoustic impedance bridge. Two out of 12 Ss gave obvious anticipatory conditioning responses; four other Ss also gave anticipatory reactions, but there was some doubt concerning these results. The remaining six Ss failed to condition. Application of the results are discussed in connection with protection from noise and future lines of research are suggested.

Self-paced and irregular methods of subjective estimation of pain

Sixteen Ss estimated the pain produced by isometric muscle contraction maintained to exhaustion. Two loads (25% and 40%), two scales (5- and 10-point), and two scaling methods (self-paced and irregular) were used. Pain levels were reported earlier with the 40% load (p <.01), with the self-paced method (p <.01), and with the 5-point scale (p <.01). Both the 10-point scale and the irregular reporting method produced longer response times at the terminal intensities (p <. 01).

Reaction time to changes in the tempo of acoustic pulse trains.

Response times (RTs) were determined for the detection of linear accelerations and decelerations in the tempo of subfusional acoustic pulse trains. 4 basal repetition rates (2, 5, 8, and 11 pulses/sec.) were used with 5 rates of change (0.1, 0.3, 0.5, 0.7, 0.9 pulses/sec.). RTs were a negatively accelerated decreasing function of the rate of acceleration or deceleration of the pulse trains. RTs to accelerations in tempo were faster than to decelerations but only with a base rate of 11 pulses/sec. and a rate of change of 0.1 pulses/sec. Over-all speed of response was inversely related to basal repetition rate, principally with decelerations in tempo at 0.1 pulses/sec. A model based upon the temporal analysis of the metric properties of the stimuli was insufficient to account for these results.

Perception of Rate Changes of Pulsed Stimuli

This experiment was designed to assess the efficiency of listeners in detecting changes in rate of pulsed stimuli. Each subject was given 50 trials in a counterbalanced order. The following stimulus conditions were used: basal rates of 2, 5, 8, and 11 Hz and linear rate changes of 1, 3, 5, 7, and 9 Hz/sec. Subjects listened to each basal rate for 10 sec, after which a signal light indicated that the basal rate would begin to increase or decrease. Reaction times to perceived increases and decreases of basal rate tempos were recorded. The carrier frequency of the square‐wave pulses was 1000 Hz. The intensity was 70 dB (SPL). An analysis of variance indicated: (1) Reaction time was a negatively accelerated decreasing function of rate of change; (2) The over‐all effects associated with basal rate and direction of change were not significant. But both parameters interacted with rate of change; (3) Increases in tempo were detected more quickly than decreases in tempo only at high basal rates and slow rates of c...

Some Factors Influencing the Release from Masking

The general purposes of these experiments were to: (1) replicate earlier findings that release from masking could not be obtained using a pure‐tone masker, (2) determine whether the release from masking could be obtained for remote masking of low‐frequency tones by higher‐frequency noise, and (3) determine if there was a relation between the amount of masking and the release from masking. Results indicated that, in confirmation of earlier work, release from masking could not be obtained using a pure‐tone masker. Also, the use of high‐frequency noise to mask lower‐frequency tones did not result in release from masking. Research on the possible relation of the amount of masking to the amount of release from masking is still in progress.