Human Ss Research Articles

Sex Differences in the Sense of Time: Failure to Replicate a 1904 Study

McDougall ( 1904), Yerkes and Urban ( 1906), and other early investigators reported sex differences in time estimation by human Ss, and more recent studies ( Loehlin, 1959) have reported no difference. This replication of McDougall's study followed his procedure as reported with the addition of more Ss and variables. Forty male and 78 female students in introductory psychology estimated four intervals (15, 30, 60, 90 sec.) under four conditions (listening to E read, crossing our 77zs, waiting, counting) by the method of verbal estimation at one of five sessions throughout the day. Differences between mean estimates given by males and those given by females were not significant for any of the conditions and were opposite in direction to what would be expected from McDougall's resulcs. Our obtained differences among the conditions were similar in rank but different in magnitude. McDougall's Ss overestimated all intervals with one exception; the present Ss underestimated all intervals. Additional hypotheses investigated concerned the influence of the time of day at which the estimates were made (Thor & Baldwin, 1965), the effect of the onset of the menstrual cycle, and the importance of psychosexual role identification (PRI) as measured by the Gough femininity scale (Gough, 1952). None of these variables s~gn~ficantly affected time estimates of men and women. However, the relation of b~ological sex and scores on PRI needs particular clarification in fumre research. Assuming the early studies were accurate, Loehlin's hypothesis of changing cultural roles as a determinant of time perception may be essentially cotrecc.

Human learning in a simplified contingent discrimination situation

Human Ss attempted to master discrimination tasks involving four displays containing nonsense forms, here schematized as ab, ba, cd and dc. The tasks proved difficult when position was reinforced in a way that made the distinction ab-ba vs. cd-dc relevant.

A study of cardiac conditioning in man

Conditioning procedures for EEG, ECG, and PGR responses were evaluated in 23 male and female human Ss. A 5 sec. 310 cps tone served as the CS+; a 130 cps 5 sec. tone served as the CS−. The US was a 10 msec. 6 ma shock to the finger. After orienting responses had extinguished, conditioning trials were initiated and continued until the S showed conditional responses on 5 consecutive occasions. PGR and ECG results were in accord with the findings of other authors working on animals. The significance of the responses studied was discussed in terms of data recorded by other investigators.

Postcriterion Insertion of a Second Relevant Dimension in a Simple Discrimination Problem

Thirty-one human Ss participated in a discrimination problem having three stages. Stage I involved one relevant dimension and one irrelevant dimension. Ss were trained to a criterion of eight successive correct responses. After reaching criterion on Stage I, Ss began Stage II, in which both the relevant and irrelevant cues from Stage I were maintained, and one more relevant and one more irrelevant dimension were added. At this point, it was possible for Ss to solve the problem by responding to the “old” relevant cue, the new cue, or both. Certain theories predict a sampling of the inserted cues; others predict they will not be sampled. In Stage III, the relevant and irrelevant cues from Stage I were dropped out. Solution of the problem could be gained only by responding to the cues inserted in Stage II. A control group was overtrained on Stage I and then went directly to Stage III. The data supported theories predicting sampling of all cues in Stage II.

A new type of concept learning situation.

Data obtained from four groups of human Ss suggest that general concepts of stimulus identity and distinctness are learned from discrimination tasks involving few or many exemplars of these concepts.

Preference and switching under ratio contingencies with humans.

Preference was studied by permitting human Ss to make switching responses which controlled the programming of components of various two-component multiple-ratio schedules. The results show that humans prefer (switch to) components with the smaller ratio requirement and the greater amount of reinforcement per occurrence of reinforcement under FR contingencies. No differential preference was observed when the multiple-ratio schedule consisted of FR and VR components equated for ratio requirement and reinforcement amount.

Vestibular sway: Parameters of the eliciting stimulus

Postural sway was elicited in human Ss using various combinations of low frequency-low amplitude sinusoidal electrical stimulation at the mastoid processes. Amount of sway was a V-shaped function of the stimulus frequency at low amplitude and an inverted V function at the higher amplitude. Amplitude-frequency combinations optimal for eliciting overall sway were different from those most suitable for use in conditioning.

Positive reinforcement: A test of the Premack theory

Two human Ss were tested on a key pressing task in which two keys produced the same reinforcer, counter points, but on different reinforcement schedules. The results of a contingency arranged between the two keys supported Premack’s reinforcement theory; not only do high rate responses reinforce low rate responses, but they do so even when both responses depend on the same reinforcer.

Some physical determinants of viewing time under three instructional sets

One-hundred fifty human Ss viewed 32 patterns under neutral (N), pleasingness (P), or interestingness (l) instructional sets. An analysis of variance indicated that patterns with larger areas were viewed longer than patterns with smaller areas under all conditions; however, this effect was more pronounced under the P and I conditions than under the N condition. Patterns containing 9-sided shapes were viewed longer than those containing 3-sided shapes under the N and I conditions, while the reverse was true for the P condition.

Transfer of response in visual recognition situations as a function of frequency variables.

Abstract : A series of 6 experiments investigated the principles required to account quantitatively for responses of human Ss to new combinations of cues following discrimination learning. In the training phase of each experiment, Ss learned to make identifying responses (numerical labels) to sets of stimuli (pairs of nonsense syllables) under a paired-associate procedure. After a fixed number of acquisition trials Ss were tested on stimulus compounds involving new combinations of the training cues. In all experiments a substantial proportion of variance in the test data was accounted for by a model embodying the additive rule and the probability matching rule of stimulus sampling theory. In cases when training had been conducted under standard discrimination paradigms, responses to test compounds were quite well accounted for by this model without auxiliary principles. Ss exhibited preferences for low ambiguity cues in test compounds only when this preference had been differentially reinforced during training. Under a variety of circumstances, predictions from the stimulus sampling model could be improved by the addition of a 'relative novelty' principle, stating that, other things being equal, Ss tend to sample from test compounds the cues that had occurred least frequently during previous training.

Duration of looking and number of brief looks as dependent variables

The duration for which human Ss exposed themselves to stimuli before responding on simultaneous discrimination problems varied with stimulus difficulty, discrimination reversal and reinforcement schedule.

Instrumental behavior during sleep.

ABSTRACTRepetitive auditory stimuli were used to examine the ability of human Ss to sustain instrumental motor responses during sleep. A majority of simple (one tone) and discriminative (two tones) responses occurred without distinct electrographic signs of awakening. Punishment for response failure, which changed neutral stimuli to warning signals, increased the probability of correct responding, particularly to stimuli which did not evoke the alpha rhythm.Correct responding was a decreasing function of Stages 1, 2, and 3 plus 4, in that order. In Stage REM, however, response probability was markedly affected by the nature of the stimulus. When the stimulus was converted from a neutral to a warning signal, the probability of responding was raised from nearly zero to levels approximating those of other low‐voltage EEG stages. These results suggest that while low responsiveness in Stage 4 may be due to physiological depression. Stage REM is a state of activation in which external stimuli are normally blocked. Contingent reinforcement, by changing the significance of the stimulus, modifies this occlusion‐like phenomenon, permitting appropriate responding.

Stimulus distinctiveness and visual discrimination performance.

The basic question investigated was whether the D (Distinctiveness) scale (Murdock, 1960) which was found useful in predicting accuracy of identification of stimuli in the method of absolute judgment with human Ss could also be applied to a visual discrimination problem in rats. Each of four matched groups of three rats was first trained to jump to one of four white circles on black background 2.405, 7.069, 14.190, and 23.760 sq. in. in area, respectively. After reaching criterion on single stimulus jumping, each S received 24 fourstimulus discrimination trials. Response measures collected were: responsiveness, latency, and accuracy. X' was used to test the adequacy of the fit bemeen the theoretical Distinctiveness distribution and that of each response distribution. Failure to rcject the null hypothesis will, in each case, support the efficacy of the D-scale prediction of empirical data.

Learning set with intra-problem stimulus variation.

Thirty-six discrimination problems of a new type were presented to teen-age human Ss. Each problem contained four trials, and each trial involved a choice between a constant and varied stimulus. The constant stimulus appeared on all trials within a problem The varied stimulus was different on every trial. There were six experimental groups, representing orthogonal combination of a three-treatment reinforcement variable and a two-treatment response vs nonresponse variable. The reinforcement variable involved the following treatments, listed in ascending order of difficulty: constant stimulus correct on all problems, varied stimulus correct on all problems, constant and varied stimuli correct alternately over problems. The response vs nonresponse variable was applied only to Trial 1, and its effects were evaluated on later trials, which showed that the nonresponse treatment was more difficult.

Effect of suggestion upon experimental pain response parameters.

The differential effects of permissive and non-permissive instructions upon pain threshold and pain tolerance were studied in 43 healthy human Ss, using cutaneous electrical stimulation. Non-permissive instructions resulted in very significant increases in both pain tolerance and pain sensitivity range, but no significant changes were observed for both pain threshold and detection threshold. Therefore, Gelfand's hypothesis, stating that pain threshold and pain tolerance have differential loadings of physiological and psychological components, was supported. It was also found that the left or non-dominant hand was consistently more sensitive to pain than the right hand. This result is consistent with Wolff's and Jarvik's suggestion that lateral dominance is important in pain perception.

Stimulus Compounding and the Attainment of Conjunctive and Disjunctive Concepts

Stimulus patterning was found to have a differential effect on the ease with which human Ss attained conjunctive and disjunctive concepts. Twenty-four undergraduate Ss were given eight disjunctive training problems and tested on a choice problem for which both conjunctive and disjunctive solutions were possible. On the test problem, more conjunctive solutions were offered when the stimulus dimensions were contained in a single geometric stimulus. More disjunctive solutions were offered when the dimensions were spatially separated on each instance. The former instances were assumed to allow for more stimulus patterning than the latter. It was concluded that stimulus patterning imposes a limiting condition on the efficacy of disjunctive-concept training, when tested by transfer on a choice problem for which a conjunctive solution is also possible.

Complex discrimination with two stages of solution.

A 4-display contingent identity discrimination design was combined with a 4-display contingent position discrimination design to produce a merged task whose 8 displays appeared repeatedly over a sequence of trials. Human Ss solved the contingent identity portion of the task first in nearly all cases and maintained a high level of accuracy on the solved portion while coping with the remainder. Experimental variations related to the visual distinctiveness of the two portions proved unimportant.

Effect of Event Run Structure on Prediction of Recursive Binary Sequences

The acquisition and prediction of recursive sequences by 150 human Ss was examined in two experiments. In general, errors per response increased with alternations in the schedule. Cycles to solution tended to increase with an increased number of runs but was not clearly related to run length or heterogeneity. Two stages of acquisition were indicated. The response-recall stage was demonstrated by S's early approximation of run lengths. Furthermore, on most schedules errors per response approached a pre-solution minimum of one error per two alternations by the middle of the acquisition process. The associative hook-up, response-ordering stage of pattern acquisition was usually characterized by an all-or-none shift from run length matching to event matching.

Drug-personality interaction in the learning of a nonsense syllable task

Summary.-DiMascio, et 01. have demonstrated that drugs produce differential effects in two personality types. The effects of three drugs (chlorpromazine, trifluoperazine, and secobarbital) on learning (nonsense syllables) were examined in individuals pre-selected according to the criteria set forth by DiMascio, et al. Drugs improved learning in one personality type only. The importance of drug-persona:icy interaction in psychopharmacologic studies is stressed. This report presents data on the learning of a nonsense syllable task by human Ss, of two contrasting personality types, after ingestion of three psychotropic drugs. These two personality types are those delineated by Klerman and DiMascio and in whom it was noted that drugs react differentially (Klerman, DiMascio, Greenblatt, & Rinkel, 1959). One type (Type A) was composed of extroverted, athletically oriented individuals, the other (Type B) of inuospective, intelleccually oriented individuals. Eight Type As and 8 Type Bs were tested under each of eight drug conditions: chlorpromazine (cpz), 100 and 200 mg.; trifluoperazine (tpz), 8 and 16 mg.; secobarbital (seco), 100 and 200 mg.; and placebos (twice). A doubleblind technique was used and drug administrations were rotated using a factorial design. At the time of peak <rug action, Ss were presented a list of 10 three-letter consonant nonsense syllables. Afcer presentation of the syllables, a I-min. task (simple addition) was interposed before Ss were asked to recall correctly as many of the syllables as possible. Eight equivalent lists of nonsense syllables had been constcucted by equating 1is:s for both association value and log frequency value. Each S was tested once on each list and the order of administration of lists was counterbalanced among drug conditions. Two measures of learning (recall ability) were the number of nonsense syllables attempted and [he per cent of these recalled correctly. Afcer placebo there was essentially no difference between the two personalicy types. When Ss were considered as one group, the only significant drug effects noted were a decrement in the number attempted after 200 mg. seco and an increment in number attempted after 8 mg. tpz. None of the drugs appeared to alter accuracy. When the data were cnalyzed separately for the two types, the As showed 'From the Psychopharmacolog~ Research Project of Massachusens Mental Health Center, 74 Fenwood Road, Boston, hlassachussetrs. Criteria for the two personality types are available from the authors.

Absolute and differential cuing of successive reversals.

Successive reversals for a single pair of stimulus alternatives were signalled by means of a “differential” cuing method or 1 of 2 “absolute” cuing methods. Under differential cuing, there were 2 extra stimuli that corresponded to reversal and nonreversal, respectively. Under absolute cuing, there was only 1 extra stimulus, but its absence served as 1 signal and its presence served as another. Both possible ways of pairing presence vs absence with reversal vs nonreversal were studied. There were 30 human Ss divided equally among the 3 methods. Differential cuing was the most difficult method. Absolute cuing was least difficult when presence of the extra stimulus was coupled with reversal and absence of the extra stimulus with nonreversal.