Concerning the role of perceptual factors in the serial position effect

The experiment described here addresses itself to the serial position effect of recall, and in particular to the cause of primacy. Two of the three theories discussed here (selective rehearsal and proactive interference) postulate competition between items during the storage interval as a cause of primacy, acquisition being assumed to be equal for all items. The third theory (differential perceptual processing) places the locus of the effect prior to the storage stage, and does not hold interactions between items to be essential to the effect after encoding. The experiment used this distinction between the two classes of theories, storage of the whole presentation (and hence interactions during storage) not being required. Only one word from each list was recalled, and this item was indicated to S on presentation, thereby eliminating the necessity to attempt to encode all items. The storage-interaction theories predict no primacy for the recall of individual items in this experiment, but the initial member of the list was recalled more often than the third member. This example of primacy lends support to the argument that the trace strengths of items are not always equal immediately after presentation.     

General software for an on-line eye-movement recording system

A general on-line eye-movement recording system is described which consists basically of (a) some on-line instrument capable of displaying a visual scene, (b) a device to measure eye position and output position information in the form of electrical signals (c) an analogue-to-digital converter, and (d) a computer. General software for such a system is discussed with emphasis on subroutines which perform calibration and which continuously monitor eye position.     

Cognitive models of class structure and explanations of social outcomes

In this paper we argue that people's explanations of a wide range of social outcomes occur within a framework of expectations derived from beliefs about the pervasive influence of social class on individuals' life-chances. This claim is tested by examining the effect of varying the social class origins of vignette characters on judgments and explanations concerning their outcomes. Four domains of social activity are examined: occupational attainment, educational achievement, relationship success, and unemployment. In all of these areas, the class background of the characters was found to be associated with different outcome expectations, future expectations, judgments of responsibility and differences in the ways in which outcomes were explained. The results are consistent with the claim that people have cognitive models in which social class background is associated with particular social outcomes across a range of activities, and that these models are reasonably accurate representations of the relationships between social class and life-chances. This suggests that contrary to theories which have stressed the individualistic nature of belief systems in western societies, social class forms an important part of the popular representation of the influences on occupational, educational and relationship success.     

Changes in Income Predict Change in Social Trust: A Longitudinal Analysis

Social trust is a psychological variable important to politics, the community, and health. Theorists have predicted that socioeconomic status determines social trust, but also that social trust determines socioeconomic status. The current study tested the viability of both causal directions using longitudinal data from representative samples of the United States and the United Kingdom. Results demonstrated that a model where increases in socioeconomic status (measured by income) predict increases in social trust is more viable than a model where increases in social trust predict increases in socioeconomic status.     

Learned changes in stimulus representations (a personal history)

Almost 40 years ago I began what turned out to be a programme of research on the way in which experience can change the effectiveness of the events used as stimuli in standard associative learning procedures. In this personal history I will describe my early (failed) attempts to find evidence for the acquired distinctiveness of cues, and my conclusion that experience tends to reduce, not enhance the associability of stimuli. I then go on to describe my attempts to square this conclusion with the stubborn empirical fact that, in some circumstances, pretraining with (or preexposure to) stimuli, can facilitate subsequent discrimination between them. I describe experiments (conducted mostly with rats as the subjects) showing how some of these effects can be explained in associative terms. Others, however, seemed to demand an explanation in terms of a new learning process that modulates the effective salience of stimuli. I go on to describe attempts to specify the nature of this process, and (bringing the story up to date) to describe recent experiments investigating the effects of salience modulation in human perceptual learning.     

An experimental investigation of the modifiability of the temporal structure of spontaneous speech

This study attempted to test the hypothesis that the temporal structure of spontaneous speech is modifiable by reinforcing and punishing pauses, of a certain duration, in an operant conditioning situation. Pause rate was significantly affected by these contingencies: moreover, rate of change was rapid, indicating a prepared association between pausing and such contingencies. This study also attempted to test the hypothesis that there is a class of noncognitive pauses in monologue by punishing UPs to determine if UPs can be eliminated without affecting speech content. Although this manipulation did lead to a decline in pause rate, a significant increase in the amount of filled hesitation, particularly in repetition, resulted. This suggests that the overall amount of hesitation is fixed by the cognitive demands of the task but that a speaker is able to adapt to different interactional contexts by varying the category of hesitation used for cognitive planning.     

Hindsight bias from 3 to 95 years of age

Upon learning the outcome to a problem, people tend to believe that they knew it all along (hindsight bias). Here, we report the first study to trace the development of hindsight bias across the life span. One hundred ninety-four participants aged 3 to 95 years completed 3 tasks designed to measure visual and verbal hindsight bias. All age groups demonstrated hindsight bias on all 3 tasks; however, preschoolers and older adults exhibited more bias than older children and younger adults. Multinomial processing tree analyses of these data revealed that preschoolers' enhanced hindsight bias resulted from them substituting the correct answer for their original answer in their recall (a qualitative error). Conversely, older adults' enhanced hindsight bias resulted from them forgetting their original answer and recalling an answer closer to, but not equal to, the correct answer (a quantitative error). We discuss these findings in relation to mechanisms of memory, perspective taking, theory of mind, and executive function.     

Analysis of us-preexposure effects in appetitive conditioning

In two experiments, rats received preexposure to one type of food followed by autoshaping in which presentation of one lever was associated with the preexposed food, and presentation of another lever with a novel type of food pellet. In both it was found that acquisition of the leverpress response occurred more readily on the lever associated with the novel food. This example of the US (unconditioned stimulus) preexposure effect is not to be explained in terms of the development of competing responses during preexposure. Explanations in terms of blocking by contextual cues and of habituation to the US are considered.     

Social influence in pigeons (Columba livia): the role of differential reinforcement

Socially-influenced learning was studied in observer pigeons that observed a demonstrator in an adjacent chamber performing a target response comprising standing on a box and pecking a key 10 times. In Experiment 1 there was no evidence for social learning in the absence of reinforcement of the observer's behavior. When the target response was already established in the observer's repertoire, but was not differentially reinforced in relation to the demonstrator's behavior, rates of extinction were not influenced by the demonstrator's behavior (Experiment 2). Reinforcement of the observer's target response in the presence of the modeled target response, and not in its absence, resulted in control of the observer's responding by the behavior of the demonstrator (Experiments 3 and 4). This control was extended in Experiment 5 to deferred responses that occurred following a delay since the demonstrator's target responses. The acquisition of social influence depended on differential reinforcement of the observer's target response, with the demonstrator's target behavior serving as the explicit discriminative stimulus.     

Endogenous cueing effects for detection can be accounted for by a decision model of selective attention

Psychonomic Bulletin & Review - Spatial cues help participants detect a visual target when it appears at the cued location. One hypothesis for this cueing effect, called selective perception,...