Method Of Stimulus Presentation Research Articles

A perceptual comparison between paired stimulus and single stimulus methods of presentation of the fluent utterances of stutterers

This investigation compared tape recordings containing the fluent utterances of treated stutterers with those of normal speakers as paired stimuli and single stimuli as presented to 20 sophisticated judges. Fluent utterances were obtained from stutterers successfully treated in one of the following programs: (1) Van Riperian, (2) metronome-conditioning speech retraining, (3) delayed auditory feedback, (4) operant conditioning, (5) precision fluency shaping program, and (6) holistic therapy. In addition, a group of partially treated stutterers were included. The original tape recordings containing matched samples of the fluent utterances of a stutterer and normal speaker were presented as paired stimuli. These paired samples were then separated, randomized, and assembled individually on another tape recording and presented as single stimuli to the same judges. The results of the statistical analysis indicated that the fluent utterances of treated stutterers was perceptibly different from the fluent utterances of nonstutterers, regardless of the method of stimulus presentation.

Directional hearing sensitivity of the bottlenosed dolphin (Tursiops truncatus) in the vertical plane

The ability of the dolphin to detect pure tone signals presented from directly ahead, with noise presented from various vertical angles was determined behaviorally for pure tone frequencies of 30, 60, and 120 kHz. The animal's position at the centerpoint era 3.5-cm arc was fixed by requiring firm contact on a biteplate. Using a yes-no response procedure, vertical directional sensitivity was examined by varying the noise levels and determining masked thresholds via a tracking method of stimulus presentation. Polar plots of the threshold points for the three frequencies generally showed a narrowing of receiving beam patterns with increased frequency. Maximum sensitivity occurred between five and ten degrees above the midline of the mouth. Sensitivity dropped more sharply with increasing angle above the midline rather than below, as might be expected with an animal that hears via the lower jaw. These receiving beam patterns show close agreement with the echolocation pulse transmitting beam patterns reported by Au, Floyd, and Haun [J. Acoust. Soc. Am. 64, 411–422 (1978)]

Influence of context and rate of speech on stop–consonant recognition

The effects of speaking rate and of contextual (with carrier phrase) and “isolated” (carrier phrase eliminated) methods of stimulus presentation on word-initial stop-consonant recognition were studied for 30 young adult listeners. Meaningful words and electronically modified subsegments were used to assess their relative contributions to consonant recognition as a function of varying speaking rate and context conditions. Generally, listener performance was exceptionally high for all conditions. However, subject’s performance indicated that the presence of a carrier phrase significantly facilitated target-word identification. Rate of speech had no significant main effect on recognition performance even though considerable change in transition length was evidenced for both non-moderate rate speaking conditions. But, for the target word “omit” condition, rate of speech was observed to influence the stability of the across-word boundary VC transitional cue more so than the within-word CV transition cue. It was also found that within-word CV transitional information was more perceptually potent than across-word boundary transitions. The findings suggest that the cue strengths of phonetic segments associated with consonant perception change as a function of context–rate interaction.

On the Development of the Augmentation Principle: A Perceptual Approach

Previous research in the development of causal schemata has relied upon verbal descriptions of behavior to convey causally relevant information. In the present study, however, a perceptual analogue of Kelley's augmentation principle was created in animated films depicting the movements of 2 objects toward a goal--1 which overcame an obstacle (inhibitory cause present) and 1 which did not (inhibitory cause absent). Both forced-choice and scalar measures indicated that kindergarten, second, and fourth graders all perceived greater motivation (internal facilitative cause) in the inhibited than noninhibited object, but that age differences emerged in the ability to explain these responses. In a second experiment, the 2 target objects were inhibited by obstacles of different sizes. For this quantitative version of the principle, age differences emerged for all measures; fourth graders and most second graders responded in accord with augmentation-principle predictions. These results were compared with the earlier findings that kindergarten and fourth-grade children did not understand this principle. The contrasting methods of stimulus presentation were discussed and implications of this technique for attribution research were noted.

Effectiveness of social reinforcement as a function of contingent and noncontingent satiation

The social satiation effect is the inverse relation between the availability of a social stimulus and its subsequent efficacy in a reinforcing role. According to a suggested cognitive-interactive theory, the satiation effect is mediated by children's attributions of contingency between their own behavior and the experimenter's actions in the satiation treatments. Perceived contingencies depend, at least to an extent, on actual contingencies, and it was therefore predicted that a satiation effect would be observed only for groups presented in the satiation treatment with noncontingent social stimuli but not for groups presented with contingent stimuli. Middle-class 5- and 7-year-old children were subjected to a 10-min waiting period in which the stimulus word “Yafeh” (“good” in English) was presented 2 or 20 times, contingently or noncontingently. They were then given a 75-trial binary discrimination test: correct responses were reinforced with “Yafeh”. The hypothesis was confirmed in the analysis of variance. However, the predicted difference between the slopes of the contingency and noncontingency conditions was found clearly only in the older sample, while the younger children were more influenced by the number of social stimuli presented in the treatment (satiation) and less influenced by the method of stimulus presentation.

Influence of Auditory, Visual, and Audio-Visual Stimulus Presentation Methods on Estimates of Transition Probability in Speech

Estimates of transition probability derived from auditory, visual, and audio-visual presentations of stimulus material (40 simple conversational sentences) were compared for 3 groups of 100 college students and found to be highly correlated.

Effects of Stimulus Presentation and Instructions on Pure-Tone Thresholds and False-Alarm Responses

The effects of three instructional sets (conventional Carhart-Jerger, strict, and lax) and of two stimulus presentation methods (continuous tones, pulsed tones) on pure-tone thresholds and false-alarm responses were determined for 20 male subjects. False alarms were tallied during hearing measurement periods and during 30-second time-out periods totaling nine minutes of time-out per subject. Results showed that 50% of the subjects made false-alarm responses to some extent at 250, 1000, and 4000 Hz. Instructions and stimulus mode, along with frequency, affected the number of false alarms, but thresholds under the experimental conditions were unchanged. It is suggested that a method for assessing and controlling false alarms is an important clinical consideration.

Paired-associate Learning in Young and Old Adults As Related to Stimulus Concreteness and Presentation Method

This study investigated the learning of young and old adults as related to two variables, stimulus concreteness (low vs. high) and presentation method (recall vs. multiple choice vs. associate matching). The main findings were: (a) the elderly did not perform as well as the young adults, (b) for both age groups performance was better for the pairs with concrete stimuli than for the pairs with abstract stimuli, and (c) for both age groups performance was best with the associative matching method and poorest with the recall method. The paired-associate performance of the elderly is characterized by deficiencies in both response learning and associative learning.

Play desensitization of fear of darkness in preschool children

Systematic desensitization therapy (SDT) is considered to be a technique of established effectiveness in reducing monosymptomatic fears (Paul, 1969a, 1969b), yet little systematic research has been done to investigate the merit of desensitization procedures in modifying children's behavior. The few available controlled studies (Miller et al., 1972; Obler and Terwilliger, 1970; Oliver, 1971) on desensitization with children have produced equivocal results. Although imagery and relaxation have been reported of benefit when used separately (Graziano and Kean, 1971; Lazarus and Abramovitz, 1962), evidence suggests that the usual combination of imagery and relaxation is not effective in reducing children's fears (Miller et al., 1972). Investigators in this area have often modified traditional SDT to include alternatives to imagery such as pictures, drawings, play (Cassell, 1965; Lazarus, 1960; Obler and Terwilliger, 1970; Patterson, 1965), or in vivo exposure to the feared stimulus (Obler and Terwilliger, 1970). Relaxation has often been replaced with other responses thought to be incompatible with anxiety such as eating (Jones, 1924). Another deviation from traditional SDT has been the delivery of positive reinforcement (food, praise, or toys) contingent upon the child's approaching the feared object (Obler and Terwilliger, 1970; Patterson, 1965). On the basis of such varied techniques, it is impossible to determine which of these procedures constitutes an effective treatment method for children. In the following study, three desensitization procedures involving graded exposure to the feared stimulus (darkness) through symbolic play, were compared to no-treatment and placebo control groups under differing instructional sets. Treatments were designed to determine the therapeutic efficacy of play as a method of stimulus presentation with children, and to determine whether reciprocal inhibition, extinction, operant reinforcement, or instructional set contribute to fear reduction in desensitization with children.

Figure and ground, methodology, and the spiral aftereffect.

The color of ground against which a black spiral pattern was seen to rotate was a significant factor in determining duration of latency but not duration of aftereffect. Reasons are given why the tachistoscopic method of stimulus presentation employed by the authors is considered superior to other methods of stimulus presentation used in spiral aftereffect research.

Intellectual Ability, Concept Rule and Effectiveness of Selection and Reception as Methods of Stimulus Presentation

Selection and reception concept-attainment paradigms were compared in a study employing a 2 × 2 × 2 × 2 repeated-measures factorial design in which the variables were (a) paradigm (selection or reception), (b) concept rule (conjunction or conditional), (c) intellectual ability (high or low), (d) problems (two per S). Results indicated that with regard to the number of cards to solution: reception was superior to selection, the conditional rule was more difficult than the conjunctive, the performance of Ss of high intellectual ability was better than that of Ss of lesser ability, improvement occurred from Problem 1 to Problem 2. In addition, the interaction of intellectual ability and paradigm was statistically significant as was the interaction of paradigm and concept rule.

Verbalizing the Rule in a Sorting Task: A Comparison of Normals and Retardates and Methods of Stimulus Presentation

Retardates with a mean MA of 6.3 and a mean CA of 12.8 were matched with normal MA and CA controls and presented with a multidimensional sorting task. The groups did not differ appreciably in number of trials to reach a sorting criterion; but probability of verbalizing the solution, once criterion was reached, was a direct function of age and IQ, with retardates being inferior to both Ma and Ca controls. For the younger normals, the successive method yielded more frequent verbalization of the correct concept than the simultaneous method, but this effect was not significant for the retardates. The relevant stimulus dimension also determined success in verbalizing the rule.

Stimulus-presentation methods and ability to shift dimensions in color-form preference of retardates.

A color-form sorting task was given to 40 institutionalized male retardates divided into two groups equated in mental age. Part I, a preference test, required that 8 stimulus figures, varying in color (red or green) and form (triangle or square), be sorted into 2 bins each marked by a comparison stimulus-figure resembling test stimuli on only one dimension. In Part II, stimuli were again presented but with the instructions to shift the basis of categorization. The procedure with both groups differed only in the method of stimulus presentation; one group received 8 figures simultaneously, the other successively. Retardates in general preferred color to form in categorization and ability to shift dimensions is facilitated by successive presentation.

Some Variables of Strategy Selection in Concept Attainment.

The present study investigated the variables of method of stimulus presentation, type of focal instance, type of strategy, and sex, in a conjunctive concept attainment task. The results indicated that an all positive series of focal cards resulted in the most efficient performance. The all negative-specified group was significantly better than the all negative-unspecified group. There was no significant difference between a focus gambling strategy and a conservative focusing strategy. The simultaneous method of stimulus presentation was shown to be superior to a successive method of presentation. There was no finding of a sex difference in concept attaining ability for each experimental condition.

Olfactory power law exponents and water solubility of odorants: A comment on Cain’s (1969) study

Cain (1969) compared the exponent of the power law for olfactory intensity from seven chemicals of a diverse chemical nature and found that the more water soluble the substance, the higher the exponent. This correlation held under two methods of stimulus presentation; olfactometric methods produced higher exponents than from sniffing at cotton wool soaked in odorant, but the relative values of the exponents remained unchanged. Cain gives no variance measures for his group exponents, nor is he completely clear how these were obtained. He stated that certain of his data points exhibited excessive variability, and that there was in the exponents yielded by individual Os. This being the case, it would have seemed incumbent on Cain to display the robustness of his assertions by some statistical justifications. Cain cited Jones's (1958) results for six odorants, which followed the same trend as his own, but again, no individual measures were available for differences between chemicals to be checked statistically. A number of studies have emerged from this laboratory, citing individual exponents, or variability thereof, these measures having been obtained by a least-squares linear regression of log tJ; on log ¢. Using an Ough and Stone (J 961) olfactometer, Gregson et al (1969) and Mitchell and Gregson (1968, 1970) have not been able to support Cain. They have found that for eugenol, a chemical of very low water solubility, exponents can range from 0.55 to 0.96 (which is higher than the highest value he quotes for water-soluble substances) with dependence upon factors such as scaling method, form of response mode, anchor stimulus intensity, explicitness of anchor, stimulus range, number of stimuli, and others. The adjective apparent is used advisedly here, since the wide individual differences in exponents (SD > 0.3 for most groups) rendered statistical tests insignificant. The only dependent variable shown to have a consistent influence on exponents was the level of masking odor (Mitchell & McBride, 1970, in press); exponents for eugenol decreased (to 0.14) as the level of masking odor (n - propanol) increased. Mitchell and Gregson (in press) have compared exponents for eugenol with water-soluble propanol in a repeated-measures study which tested 20 Os on four separate occasions, twice with eugenol and twice with propanol; all other things were held as equal as possible. The means of the individual exponents in each group were almost identical (0.65 and 0.63 for eugenol, 0.63 and 0.63 for propanol, with SDs ranging from 0.33 to 0.39); no differences were found between the substances. Berglund et aI (1970) have published what is perhaps the most telling evidence against Cain. They obtained exponents for 28 different chemicals of widely varying physicochemical and psychological (qualitative and hedonic) attributes. They found a very low correlation (0.27)

Experimental studies on the uncomfortable loudness level.

A number of experimental determinations of the uncomfortable loudness level (ULL) at 1000 Hz were made on several groups of normal-hearing subjects, using various methods of stimulus presentation and applying different personality measures to the subjects. The same mean levels were found for both earphone and free-field presentations. In experienced subjects the monaural-binaural difference was between 2.5 and 4 dB in different experiments. In naive subjects this difference was 6 dB. In two groups of subjects, ULL was found to be significantly negatively correlated with their test anxiety scores, but this correlation did not hold for the other two groups tested. Naive subjects showed little difference in intersubject variance with the manual or Bekesy presentation techniques.

CONDITIONAL DISCRIMINATION LEARNING IN CHILDREN: TWO RELEVANT FACTORS

DOAN, HELEN McK., and COOPER, DEBORAH L. Conditional Discrimination Learning in Children: Two Relevant Factors. CHILD DEVELOPMENT, 1971, 42, 909-290. 40 children, 5 years 3 months to 6 years 2 months, served as Ss in a conditional discrimination problem. 2 methods of stimulus presentation (random or alternative method) and 2 background conditions (red-blue or striated-black) were explored in a 2 X 2 factorial design. Generally, it was demonstrated that the type of stimulus background interacted with the method of presentation to determine both the difficulty of the problems and the strategy used to solve the problems.

Effects of Training Procedures on Recall of Auditory Sequences by Children

3 groups of preschool children were trained in short-term memory for word sequences by three different methods of stimulus presentation: (1) vocalized auditory sequences, (2) vocalized sequences with simultaneous visual stimuli, (3) vocal stimuli followed immediately by visual stimuli. Four different delay intervals between stimulus and response were utilized. The word sequences were 2, 3, and 4 words in length. The duration of the delay interval and the number of words in the sequence affected performance level. Method of training did not affect performance level but did produce significantly different gains in performance over a four-day period.

A Re-Examination of the Value of the Olfactory Power Law Exponent

The exponent value of the psychophysical power law for olfactory intensity is re-examined by olfactometric methods over two levels of standard stimulus and two types of magnitude estimation procedure. Neither the method of measurement nor the level of the standard significantly influenced the exponent. A value of 0.80 was obtained, not significantly different from a value of 0.72 determined by category scaling methods by the same authors (1968). Both values are considerably greater than previous exponents reported by other workers; the present authors attribute the differences between studies to the degree of stimulus control available in the different methods of stimulus presentation.

Impression value, instructional set, and methods of stimulus presentation as factors influencing control subjects in verbal conditioning.

Impression value, instructional set, and methods of stimulus presentation as factors influencing control subjects in verbal conditioning.