On time differences in searching for letters in words and nonwords: Do they emerge during the initial encoding or the subsequent scan?

Krueger (1970a, 1970b, 1982) has demonstrated that subjects can search for target letters within words faster than they can complete an equivalent search through nonwords, and he further demonstrated that the effect did not arise during the comparison stage. The present study involved three experiments in which the usual word advantage disappeared either when subjects knew where within a display the target item would appear (i.e., it was always the first letter), or when all the component letters were encoded into memory before the task began (i.e., a memory-search task). These data, in conjunction with Krueger's, where interpreted as localizing at least one (and possibly the only) source of the word-nonword difference in this task to the events that occur during the item-to-item transitions subjects make when scanning the letter arrays. That is, these transitions are faster for words than nonwords, and it was suggested that the time difference may emerge because although all the letters from within a word appear to be available in memory before the scan begins, this seems not to be true for consonant arrays. Given that this is the case, part of the word-nonword difference may be attributable to subsequent encoding events that would be needed for the consonant arrays as the scan moves from letter to letter.     

When visual search functions look like item recognition functions

Visual search data were collected from six Ss on three target set sizes on each of 30 days. Error level was low, and items assigned to memory sets were nonnested and changed from session tosession. For each S. the same item sometimes required a positive and sometimes a negative response (response inconsistency). Combining data over Ss and over successive 6-day blocks, visual search rates as a function of target set size were found to be linear for each of the five 6-day blocks. The slopes of the above functions (memory search time) did not differ significantly over the final four 6-day blocks, and averaged approximately.500 sec per six-character item. These results are qualitatively very similar to results obtained from item recognition studies when error level, memory set structure, degree of response’_ consistency, and practice are handled in the same way in that task. The significantly lower slope obtained on the first 6-day block is shown to be consistent with a speed-accuracy trade off interpretation when error rate is expressed per unit of processing time (percent errors/set size). Over the final three 6-day blocks, where all important parameters ofthe data were highly stable, the intercepts of the memory search functions were found to closely approximate zero, averaging .0068 sec. From this finding, along with the finding that the memory search functions are linear, it is inferred that visual search time is determined entirely by memory search time, or by memory search time and other processes which increase linearly with set size, under the conditions of this experiment. The estimate of memory search time (approximately 83 msec/character) obtained using this visual search procedure is much slower than that obtained using the item recognition procedure (approximately 35\2-40 msec/character). An explanation for this difference is proposed.     

THE INFLUENCE OF AUDITORY STIMULUS INTENSITY ON APPARENT DURATION

B erglund , B., B erglund , U., E kman , G. & F rankenhaeuser , M. The influence of auditory stimulus intensity on apparent duration. Scand J. Psychol ., 1969, 10 21–26.— apparent duration of an auditory signal of 1000 C/S was measured by the method of magnitude estimation. Ten different stimulus intensities ranging from 57 to 104 dB were used in combination with three different durations: 50, 250, and 500 msec. The results showed that the apparent duration of the signal grew as a logarithmic function of stimulus intensity. These results are consistent with the hypothesis relating apparent duration to activation level as well as with results of similar experiments involving electrical and vibrotactile stimulation.     

Short-term memory and the nature of interference from concurrent shadowing

Trigrams were presented visually or auditorily and followed by a 12 s retention interval filled with shadowing numbers or letters. Auditory memory letters followed by letter shadowing were recalled less than auditory memory letters followed by number shadowing or visual memory letters followed by either type of shadowing. The latter three conditions did not differ among themselves. An analysis of the recall intrusions suggested that forgetting of auditory memory letters followed by letter shadowing was caused mainly by a confusion between covert rehearsals and shadowing activity, while forgetting in the other three conditions was caused primarily by proactive interference from earlier memory trials.     

Psychophysiological reactions to understimulation and overstimulation

Catecholamine output, heart rate, and performance efficiency were examined in 28 Ss during two contrasting stimulus conditions, one of understimulation, and one of overstimulation. During understimulation the subject spent 3 hr performing a vigilance task, and during overstimulation he was exposed for the same time period to a complex sensorimotor test. Both understimulation and overstimulation produced a significant increase of adrenaline and noradrenaline release as compared with a control condition involving a medium amount of stimulation. Subjects who excreted relatively more adrenaline performed significantly better during understimulation, whereas subjects with relatively lower excretion rates of adrenaline tended to perform better under overstimulation. When performance efficiency was related to heart rate it was shown that high-heart rate subjects performed better during understimulation, while low-heart rate subjects performed better during overstimulation.     

OBJECTIVE AND SUBJECTIVE PERFORMANCE AS INFLUENCED BY DRUG-INDUCED VARIATIONS IN ACTIVATION LEVEL

Performance was measured by seven sensorimotor and perceptual tests given to 30 students in six successive trials, spread over five hours, before and after the intake of either 15 mg dexamphetamine, zoo mg Pentobarbitone, or a placebo. Subjective performance, level of aspiration, wakefulness, and mood were measured by a scaling method. A close agreement was found between the amount of objective and subjective improvement following dexamphetamine, whereas the objective impairment induced by Pentobarbitone was not reflected in the subjective measures. These results were examined in relation to the other indices of activation.     

The influence of sex bias upon compliance with expert power

The present study evolved from the belief that sex bias influences the degree of expert power which the expert has in relation to the perceiver. Therefore, the influence of level of expertise, sex of the expert, sex of the influencee, and sex domination of the expert's occupation upon compliance was examined. Separate experiments were conducted for the male- and female-dominated occupations. Subjects' degree of compliance was measured by their responses to three recommendations contained in an in-basket. The three-way analyses of variance revealed that only expertise significantly affected subjects' degree of compliance. Results are discussed in terms of the presence of outside recognition of competence and legitimate power.     

Minor illness and social behavior of infants and caregivers

Fourteen infants attending day care were observed during the first year of life when well and during acute minor illnesses. Comparisons of behavior during 46 afebrile illnesses and a like number of well observations revealed no differences in infant or caregiver behavior. During 24 febrile illness observations, however, infants moved less, contacted toys less, were in closer proximity to teachers, cried more, and looked at teachers more. During a subset of these febrile illnesses, in which teachers recognized that infants were ill, teachers vocalized, gave toys, looked at, touched, held, and fed infants more than when infants were well. Analysis of teacher behavior during infant crying demonstrated that infant cries played an important role in eliciting social responses from teachers during febrile illness. These results suggest that both caregiver perception of illness state and illness-induced changes in infant behavior contribute to increased sociability by caregivers during acute febrile illness.     

Life and job satisfaction: Is the job central?

The nature of the causal relationship between life and job satisfaction in a sample of males and females working in a variety of jobs was investigated. Results suggest that the life satisfaction causes job satisfaction hypothesis is more tenable than the reverse.