On the dynamic nature of response criterion in recognition memory: Effects of base rate, awareness, and feedback.

The authors examined whether participants can shift their criterion for recognition decisions in response to the probability that an item was previously studied. Participants in 3 experiments were given recognition tests in which the probability that an item was studied was correlated with its location during the test. Results from all 3 experiments indicated that participants' response criteria were sensitive to the probability that an item was previously studied and that shifts in criterion were robust. In addition, awareness of the bases for criterion shifts and feedback on performance were key factors contributing to the observed shifts in decision criteria. These data suggest that decision processes can operate in a dynamic fashion, shifting from item to item. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Forgetting of stimulus attributes: Methodological implications for assessing associative phenomena.

Differential responding to changes in the stimulus situation, long central to the concept of stimulus control, also provides the implicit conceptual basis for assessing the nature of a variety of associative relationships. However, there is substantial evidence that the perception of stimulus similarity is not a static property. Generalization gradients to contextual as well as discriminative stimuli flatten over time, and this increase in perceived similarity presumably reflects forgetting of the detailed characteristics or attributes of stimuli. Methodologically, the flattening of the gradient imposes an important constraint: The effect of a stimulus shift will be highly sensitive to the length of the delay interval between training and testing. Conceptually, the loss of memory for stimulus attributes also implies that the sources of interference in retention can increase over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Episodic encoding of voice attributes and recognition memory for spoken words.

Recognition memory for spoken words was investigated with a continuous recognition memory task. Independent variables were number of intervening words (lag) between initial and subsequent presentations of a word, total number of talkers in the stimulus set, and whether words were repeated in the same voice or a different voice. In Exp 1, recognition judgments were based on word identity alone. Same-voice repetitions were recognized more quickly and accurately than different-voice repetitions at all values of lag and at all levels of talker variability. In Exp 2, recognition judgments were based on both word identity and voice identity. Ss recognized repeated voices quite accurately. Gender of the talker affected voice recognition but not item recognition. These results suggest that detailed information about a talker's voice is retained in long-term memory representations of spoken words. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of varying stimulus size on object recognition in pigeons.

The authors investigated the pigeon's ability to generalize object discrimination performance to smaller and larger versions of trained objects. In Experiment 1, they taught pigeons with line drawings of multipart objects and later tested the birds with both larger and smaller drawings. The pigeons exhibited significant generalization to new sizes, although they did show systematic performance decrements as the new size deviated from the original. In Experiment 2, the authors tested both linear and exponential size changes of computer-rendered basic shapes to determine which size transformation produced equivalent performance for size increases and decreases. Performance was more consistent with logarithmic than with linear scaling of size. This finding was supported in Experiment 3. Overall, the experiments suggest that the pigeon encodes size as a feature of objects and that the representation of size is most likely logarithmic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Expected base rates and trait covariations in person perception.

This paper is primarily concerned with judgments about the characteristics of the general other and the incorporation of these expectancies in the judgment of specific others. Expectancies are defined in terms of (1) the perceived probability of occurrence of attributes in the general other, and (2) the perceived probability of joint occurrence of attributes in the general other. Along with other related variables, the veridicality of these expectancies are discussed. In addition, the idea of the greater informational value of atypical known behaviour about a specific other (behaviour which occurs infrequently in the general other) is considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exposure effects may not depend on stimulus recognition.

Compared the applicability of M. H. Birnbaum and B. A. Mellers' (see PA, Vol 64:00000) 1-factor (subjective recognition) model with the present author's (see record 1979-23525-001) 2-factor model to data on the role of stimulus recognition in the mere exposure phenomenon. Results of a series of linear structural equation analyses show that the 2-factor model provided a significantly greater degree of fit. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Demographic variables, base rates, and personality characteristics associated with recidivism in male delinquents.

Studied demographic variables, base rates, and personality characteristics of 455 adolescent male delinquents in 3 studies. The total population discharged from a treatment-oriented facility was followed, and data were recovered from 98%. The recidivism rate was 37.5%, which compares to the recidivism base rates found in similar rehabilitation facilities. Significantly higher rates of recidivism were found among the younger delinquents, delinquents with prior institutional experience, and delinquents who had previously run away from an institution. Measures of impulse control and foresight and planning ability derived from the Porteus Maze Test differentiated 10 recidivists from 10 nonrecidivists. A follow-up study of 68 consecutively discharged Ss from the same institution replicated the findings with respect to impulse control but not foresight and planning ability. One measure of future time perspective and some staff ratings were also related to recidivism. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

State-dependent stimulus control: cuing attributes of acute cocaine rebound in rats

General and rapid methods were developed for determining the extent of non-covalent binding between small molecules and proteins, using the model system of human cytomegalovirus protease and several drug candidates which inhibit the protease by non-covalently binding to it. The assay was performed by off-line coupling of size-exclusion methods with mass spectrometry in the following manner. The protease and inhibitor were incubated together under native conditions and then subjected to separation based on size, by use of a spin column (gel permeation chromatography) and/or a microconcentrator (ultrafiltration). The spin column selectively passed the high molecular mass (M(r)) protease and trapped low M(r) molecules. Alternatively, the microconcentrator passed low M(r) molecules and retained the protease. If the inhibitor bound non-covalently to the protease, both the inhibitor and protease passed through the spin column (or were retained by the microconcentrator). Electrospray ionization mass spectrometry was used to assay the spin column eluate (or the microconcentrator retentate) and to characterize the amounts of protease and inhibitor based on known standards. An advantage of these techniques is that a mixture containing inhibitors can be analyzed in the presence of the protease, and inhibitors with the greatest binding affinity can be identified. Non-covalent binding specificity was demonstrated using spin columns by comparing the binding affinity of inhibitors using several mutants of cytomegalovirus protease. The techniques described are applicable to the rapid screening of compound libraries for selecting substances which bind non-covalently to a known protein.     

Latency of evoked neuromagnetic M100 reflects perceptual and acoustic stimulus attributes

The latency of components of the auditory evoked neuromagnetic field has been shown to reflect, or encode, stimulus attributes. In particular, the M100 component, occurring approximately 100 ms post stimulus onset has a latency that depends on stimulus pitch, spectral complexity and presentation level. This study used magnetoencephalography to record neuromagnetic fields evoked by presentation of two-tone complexes consisting of various proportions of 100 Hz and 1 kHz energy. These are perceived categorically, as evidenced by classification and reaction time measurements. It is found that the M100 latency also varies categorically, that is, characterized by two plateau regions with a sharp interface. Thus, we find that not only does the M100 latency reflect acoustic attributes of a stimulus, but also such perceptual characteristics.     

Fear conditioned with escapable and inescapable shock: Effects of a feedback stimulus.

Four experiments, with 140 male Fischer rats, compared the level of fear conditioned with escapable and inescapable shock. In Exps I and II, master Ss that had received 50 unsignaled escapable shocks were less afraid of the situation where the shock had occurred than were yoked Ss that had received inescapable shocks. Comparable results were found in Exps III and IV, which used freezing as an index of fear of a discrete CS that had been paired with shock. Control per se was not necessary to produce the low level of fear seen in the master Ss. Yoked groups receiving a feedback signal at the time the master made an escape response showed a low level of fear that was comparable to that of the masters and significantly less than that seen in the yoked Ss without feedback. In addition, there were strong suggestions that control and feedback exert their effects through the same or highly similar mechanisms. Possible explanations for how control and the exteroceptive feedback signal produce this effect are discussed. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The psychology of the unthinkable: Taboo trade-offs, forbidden base rates, and heretical counterfactuals.

Five studies explored cognitive, affective, and behavioral responses to proscribed forms of social cognition. Experiments 1 and 2 revealed that people responded to taboo trade-offs that monetized sacred values with moral outrage and cleansing. Experiments 3 and 4 revealed that racial egalitarians were least likely to use, and angriest at those who did use, race-tainted base rates and that egalitarians who inadvertently used such base rates tried to reaffirm their fair-mindedness. Experiment 5 revealed that Christian fundamentalists were most likely to reject heretical counterfactuals that applied everyday causal schemata to Biblical narratives and to engage in moral cleansing after merely contemplating such possibilities. Although the results fit the sacred-value-protection model (SVPM) better than rival formulations, the SVPM must draw on cross-cultural taxonomies of relational schemata to specify normative boundaries on thought. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dissociative effects of stimulus quality on semantic and morphological contexts in visual word recognition.

Semantic and morphological contexts were manipulated jointly with stimulus quality under conditions where there were few related prime-target pairs (i.e., low relatedness proportion) in a lexical decision experiment. Additive effects of semantic context and stimulus quality on RT were observed, replicating previous work. In contrast, morphological context interacted with stimulus quality. This dissociation is discussed in the context of Besner and colleagues' evolving multistage framework. The essence of the account is that 1) stimulus quality affects feature and letter levels, but not later levels, 2) feedback from semantics to the lexical level is inoperative under low relatedness proportion conditions (hence stimulus quality and semantic context yield additive effects), whereas 3) feedback from the lexical level to the letter level is intact, hence stimulus quality and morphological context produce an interaction by virtue of them affecting a common stage of processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A paradoxical exposure-duration effect in the Stroop task: Temporal segregation between stimulus attributes facilitates selection.

In comparison with the situation in which target and distractor are presented until response, Stroop interference substantially decreases when the target color is removed from the display 150–160 ms after stimulus onset (W. La Heij, N. A. Kaptein, A. C. Kalff, & L. de Lange, 1995; 0. Neumann, 1986). Six experiments showed that this paradoxical exposure-duration effect is robust, that it is not due to the target's exposure duration per se, and that it is not due to an increased spatial selectivity of input selection. The present findings support and extend earlier observations that changes in the display during stimulus exposure affect attentional selection. The findings are tentatively interpreted in terms of (a) reduced duration of input selection or (b) facilitation of attribute selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Speed of form recognition as a function of stimulus factors and test anxiety.

This study evaluated the usefulness of several theories about Rorschach color shock. Using an arabic-greco-latin square design, the influence of color, pattern of color, figure, and anxiety level on response time was investigated in 192 Ss. "The influence on response time of stimulus attributes affecting complexity was confirmed. The hypotheses that highly anxious persons are greatly affected by colors are not confirmed. Partially verified were predictions made from Hullian behavior theory. It was found that drive level and figure difficulty were related to response time in that highly anxious persons became slower with increasing difficulty of figure during warm-up trials. During the test series, however, the predicted relationship was not found." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Motivation, model attributes, and prosocial behavior.

Examined the personality and situational effects that influence prosocial behavior. 112 safety- and esteem-oriented (as measured by a sentence-completion test) undergraduates were exposed to an emergency situation wherein the experimenter was ostensibly injured by an "explosion." Results indicate that there were significant situational and personality determinants of helping and imitative behavior. Overall, there was more help when Ss were interacting with an active vs a passive model. Esteem-oriented Ss were more likely to initiate helping behavior and were more strongly influenced by high-competence models. In contrast, safety-oriented Ss helped less overall and were more influenced by high-status models. Results are discussed in terms of a Person?×?Situation paradigm of prosocial behaviors. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationships among feedback sign, self-efficacy, and acceptance of performance feedback.

The researchers investigated the moderating role of self-efficacy on feedback acceptance. High-self-efficacy individuals who received repeated negative performance feedback exhibited decreased acceptance of the feedback, whereas those with low self-efficacy did not change in their acceptance. Feedback sign and feedback acceptance also had interactive effects on future self-efficacy. Those with high acceptance of positive and negative feedback after repeated trials exhibited self-efficacy levels consistent with that feedback. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of training, stimulus context, and mode of stimulus presentation on empathy ratings.

Investigated how empathy ratings made by raters trained to use the Empathic Understanding in Interpersonal Processes (EU) Scale were affected by the conditions under which the ratings were made. 54 female undergraduates served as raters. The 3 factors studied were (a) training condition, (b) context of the counselor statement rated, and (c) mode of presentation of stimuli to the raters. Results indicate that training condition was the only significant factor. The significance of this factor is discussed in terms of the possible danger in comparing studies that used different training procedures. The nonsignificance of the context and mode factors is discussed in terms of the construct validity of the EU scale. It is argued that empathy ratings should logically be sensitive to the rater's knowledge of to whom and to what the counselor is responding. As this was not the case in the present study, the construct validity of the scale was held in question. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Determinants of diagnostic hypothesis generation: effects of information, base rates, and experience

Physicians generated diagnostic hypotheses for case histories for which 2 types of diagnoses were plausible, with one having a higher population base rate but less severe clinical consequences than the other. The number of clinical and background symptoms pointing towards the 2 diagnoses was factorially manipulated. The order and frequency with which physicians generated hypotheses varied with the amount of relevant clinical and background information and as a function of population incidence rates, with little evidence of base rate neglect. Availability of a hypothesis, made possible by diagnosis of a similar case before, also made doctors generate this diagnosis earlier and more frequently. Physicians' experience affected hypothesis generation solely by increasing the availability of similar cases. The results are consistent with the use of similarity-based hypothesis generation processes that operate on memory for prior cases.     

Everyday base rates (sex stereotypes): Potent and resilient.

Undergraduate Ss studied photographs of students and estimated the heights of the pictured models. Contrary to reports of base-rate neglect, sex stereotypes regarding height (the implicit recognition that men are normally taller than women) significantly affected these estimates, even when the targets' actual height was statistically controlled. Base rates were especially influential when information about targets was ambiguous, that is when targets were pictured seated. These base-rate effects were robust, remaining significant and substantial despite efforts to lessen their magnitude. Attempts to reduce base-rate effects by encouraging Ss to strive for accuracy, discouraging their reliance on the target's sex (as a cue), or offering cash rewards for accuracy did not succeed. Informing Ss that for the sample to be judged, sex would not predict targets' heights attenuated the base-rate effect, although it remained highly significant. (PsycINFO Database Record (c) 2010 APA, all rights reserved)