Foreperiod and stuttering severity effects on acoustic laryngeal reaction time

An earlier paper presented a model of the laryngeal reaction time (LRT) paradigm that included several factors that appeared to affect LRT values. The present study assesses the effects of two of these factors: foreperiod and stuttering severity. The former was assessed by the use of 13 foreperiod durations. The latter was assessed by classifying experimental subjects as either mild or severe stutterers. Both factors significantly affected LRT values. More importantly, these factors demonstrated a composite effect on group LRT differences. Specifically, mild stutterers' LRT values approached normal values as foreperiod increased, whereas severe stutterers' LRT values remained significantly greater than normal values at all foreperiods. Results are discussed in terms of differential posturing and/or vibration initiation deficits underlying stutterers' delayed LRT values. We caution that acoustic measurements alone are insufficient to specify fully the nature of the underlying deficits.     

A comparison of LRT and VOT values between stutterers and nonstutterers

The experiment reported here found no significant group differences in laryngeal reaction time (LRT) and voice onset time (VOT) values. Rank-order correlations between the stutterers' LRT and VOT values were also nonsignificant. A model of the LRT paradigm is presented that (1) allows for systematic assessment of factors possibly contributing to the failure to replicate the often reported LRT group difference, and (2) is useful in examining the relationship between the LRT experimental condition and normal speaking conditions. We argue that two factors were particularly critical to our results. First, simple reaction time procedures included (1) a warning signal that preceded a response signal by a variable 1–3-sec foreperiod, and (2) a single response. We argue that foreperiod durations exceeded the stutterers' speech posture time for a known response. Second, the stuttering severity rating of our experimental group was less severe than ratings in other experiments.     

Alarm call responsivity of mallard ducklings: The inadequacy of learning and genetic explanations of instinctive behavior

Traditional conceptions of learning do not adequately account for the development of species-typical behavior. Developmental theory, though, can account for learning phenomena, as well as seemingly innate behavior. Developmental theory also focuses on subtle, nonobvious, as well as obvious, forms of experience throughout the life span, including the prenatal period. To illustrate the developmental approach, data on the ontogeny of alarm call responsivity in mallard ducklings (Anas platyrhynchos) are presented. This research, which was conducted both in the field and in the laboratory, identifies the particular acoustic feature of alarm calls to which ducklings are sensitive. Additional experiments have shown that normally occurring perinatal auditory experience is required for the development of behavioral inhibition (i.e., “freezing”). These experiments demonstrate the ability of developmental theory to account for phenomena that elude other, more traditional, theories.     

Experimenter effects on responses to explicitly sexual stimuli

Experimenter effects on responses to explicitly sexual stimuli were investigated in 63 single undergraduate males and 89 single undergraduate females. A completely factorial design with sex of subject, sex of experimenter, and experimenter's style of interacting (informal vs formal) as the independent factors was employed. While the variables under investigation did not have an overriding effect on the outcome measures, at least one experimenter attribute was discovered to significantly influence a large percentage of the variables assessed: The data suggest that informal experimenters permit less socially desirable responses and more generalized arousal than formal experimenters. In addition to replicating earlier work on experimenter effects, the present study serves to delineate a possible set of cues by which experimenters may influence their subjects' arousal to explicitly sexual stimuli.     

The effectiveness of reward and punishment contingencies on response inhibition

The relative effectiveness of reward and punishment on the development of response inhibition was evaluated developmentally. Forty kindergarten and forty second-graders received response inhibition training with half of each group rewarded for inhibiting and half punished for not inhibiting. Reward involved the presentation of positive reinforcers, whereas punishment involved their removal. Punishment produced more inhibition at both age levels than did reward. Transfer of inhibition training was evaluated in two tasks. Transfer effects were observed only on one of the two tasks. Reinforcement contingencies and age did not differentially influence the magnitude of transfer.     

The effect of stimulus person valence on divergent self-other attributions for success and failure

Two experiments investigated self-other attributions for success and failure. In Experiment 1, high and low achievers completed a modified IAR scale either for themselves or another. Regardless of achievement motives, more personal attribution for failure was assigned to oneself than to a neutral other. In Experiment 2, additional scales for liked and disliked others were administered and scale item importance was varied. On global and individual causal measures, neutral and liked others were credited more and disliked others less for success than oneself, and liked others were blamed less and disliked others more for failure than oneself and neutral others. Item importance produced few effects. Results were interpreted in terms of informational considerations in self-other attribution.     

Developmental changes in the lag effect: An encoding hypothesis for repeated word recall

A differential encoding hypothesis for the lag effect in free recall was tested developmentally. Fourth- and eighth-grade children and college adults were shown a list of words, with some repeated at various lag intervals. Lag functions in repeated word recall were found to vary with age. An encoding hypothesis, modified to provide specificity for the time at which differential encoding takes place, was used to account for the results. Finally, it was suggested that the lag paradigm could be utilized to assess developmental differences in processing strategies, as perhaps a more sensitive, and general, alternative to the overt rehearsal technique.