Attention switching between perception and memory

Two experiments were conducted to explore the switching of attention between perception and memory. In Experiment 1, college students performed a task that required them to cycle or switch attention between perceptual and memorial inputs. Switching times of 293 and 376 msec per switch were obtained on the basis of two formulas. In Experiment 2, the attentional load was manipulated by varying the number of perceptual and memorial inputs. Switching time increased as a function of list length, indicating that item load affects both the control processes that set attentional allocation policies and one’s ability to perform memory and/or perceptual tasks. These results suggest that modularity, or encapsulation of item and control-process systems, does not hold. A model is presented that depicts the relation between item and control-process representation in rapidly alternating attention between perception and memory.     

Attention blinks for selection, not perception or memory: reading sentences and reporting targets

In whole report, a sentence presented sequentially at the rate of about 10 words/s can be recalled accurately, whereas if the task is to report only two target words (e.g., red words), the second target suffers an attentional blink if it appears shortly after the first target. If these two tasks are carried out simultaneously, is there an attentional blink, and does it affect both tasks? Here, sentence report was combined with report of two target words (Experiments 1 and 2) or two inserted target digits, Arabic numerals or word digits (Experiments 3 and 4). When participants reported only the targets an attentional blink was always observed. When they reported both the sentence and targets, sentence report was quite accurate but there was an attentional blink in picking out the targets when they were part of the sentence. When targets were extra digits inserted in the sentence there was no blink when viewers also reported the sentence. These results challenge some theories of the attentional blink: Blinks result from online selection, not perception or memory.     

Person memory and judgment

Two general types of information about a person are considered in this article: One pertains to specific behaviors a person has manifested, and the other refers to more abstract personality dispositions or behavioral tendencies. A theoretical model of person memory that incorporates both types of information is developed. The model accounts for a large number of factors that are known to affect the recall of social information, the making of interpersonal judgments, and the relation between what is recalled and the judgments that are made. A major strength of the model is its applicability to a wide range of person memory and judgment phenomena that are observed in several different experimental paradigms.     

Attention and depth perception

The Necker cube is a line drawing with two possible solutions in depth perception. The process of interpreting a two-dimensional line drawing as a three-dimensional object was investigated using the Necker cube. Attention was directed to a local feature of a briefly presented cube, ie an angle at a vertex. The attended angle was perceived as a front part of the cube and other parts were interpreted so as to match this interpretation. Results show that the local feature to which attention was directed was interpreted first and then global features and other local features were interpreted so as to agree with the local feature interpreted initially. This suggests that the three-dimensional interpretation of the line drawing was made sequentially from the local feature to global structures.     

Social representations of drugs,causal judgment and social perception

The aim of this study was to analyse the influence of social representation on both social perceptions and social judgments. In the first stage of this study, 47 drug users and 80 ‘normal’ subjects were asked to respond to a questionnaire about representations of drugs. Three weeks later we contacted the same subjects. They were asked to answer some questions about a fictitious story in which an actor labelled as ‘a drug user’ or ‘a person’ disputed with a trader. Three different social representations of drugs were found. It was shown that these social representations were anchored in different social groups which were defined by their proximity to the world of drugs. Subjects who were themselves drug users shared an accepting or an ambivalent social representation of drugs but they also made the most negative judgements about the causes of a fictitious dispute between a trader and a drug addict. Moreover, these subjects had the most negative perception of the drug addict. Furthermore, some factors which increase the salience of social representations were studied. The effect on social perception and causal attributions of the interaction between social representations, the context and personal involvement in drugs was also shown. Some relations between the theory of social representations and the theories about asymmetrical intergroup relationships are exposed.     

Risk perception and victim perception: The judgment of HIV cases

There is a vast literature confirming that reactions to different risks are strongly affected by characteristics other than scientific risk estimates; most of this research has concentrated on mapping people's representations of sets of widely varying dangers (e.g. diseases, natural disasters, accidents). This study explored a potentially vital component of risk that cannot be studied by eliciting general reactions to many hazards: the extent to which who is at risk contributes to perceptions and judgments of a risk. While it may be preferable to assume that misfortunes affect the population uniformly, of course the truth is not so egalitarian. Thus, for both theoretical and policy reasons, it is worth exploring psychometrically representations of a particular risk as it affects different people. Using multidimensional scaling and hierarchical cluster analysis, we constructed models of respondents' representations of a disease assumed to be particularly affected by victim perception: Human Immunodeficiency Virus (HIV). Subjects rated the similarity of all possible pairs among 16 scenarios involving HIV infection; the scenarios contained information about both the victim and the method of contraction. A set of attribute scales as well as political/demographic information allowed us both to interpret the structures and to predict individual differences. The results confirmed that reactions to HIV infection are greatly affected by reactions to the victim. In particular, the perceived distastefulness and riskiness of the method of infection loomed larger than did either the overall likability of the victim or the general riskiness of the victim's behavior. Further, the salience of the most statistically influential dimension, ‘deservedness’, depended significantly on demographic and political characteristics of the respondents, suggesting that the relationship between personal values and risk perception is in part mediated by victim perception. Implications for risk perception work and public policy are discussed.     

Application of signal detection theory to perception of differences in line length

This paper is an attempt to specify the equinormal model for application to different tasks which are currently used in psychophysics (i.e. phenomenal report, detection, and 2AFC). The same set of stimuli (pairs of horizontal colinear lines) is presented in procedures which differ by the task, the probability of the signal, and the succession of the stimuli of the set. This approach leads to the specification of the sensorial and the decisional aspects of the model.The data indicate that (1) the sensitivity index d' to differences in line length is the same function of the physical stimulus independently of paradigm, as far as the same task is concerned. However, and according to the predictions, its value becomes larger by a factor of 2 in a two alternative forced choice task; (2) d' increases with stimulus exposure time; (3) latency of responses generally decreases with increasing d', and are dissimilar for correct and incorrect responses; (4) when the temporal succession of the stimuli is random the subject's criterion, x_c, is not chosen to optimize the percentage correct, which would require a dependance of criterion upon stimulus amplitude and prior probabilities.     

Attention, rehearsal, and memory for serial order

In three experiments, subjects attended to one of two simultaneous nine-digit sequences, presented binaurally in different voices (one male, one female). Substantial repetition effects (defined as gains in immediate memory performance for previously presented sequences relative to novel ones) were found for two exposure conditions: (a) one that required reproduction of the full sequence on each exposure (Experiment 1), and (b) one that required recall of a different two-digit subsequence on each exposure (Experiment 2). In Experiment 3, the following conditions produced no repetition effects, even though tests had substantial power to detect small effects: 10 consecutive presentations in the unattended voice; 4 prior presentations in a task that required attention to each digit as it was presented (but not to digit order); and 4 prior presentations in a task that required attention to digit order during their presentations. These results, together with those of previous studies, support the conclusion that repetition effects on immediate memory occur only with procedures that encourage covert rehearsal of full-sequence order on each exposure. These findings also limit the generality of others' conclusions that event order is automatically encoded for attended events, and extend previous findings showing unattended exposures to be without effect on recall measures.     

Cognitive psychology in Scandinavia: Attention, memory, learning and memory dysfunctions

The last 15 years of research on attention, memory, learning and memory dysfunction is reviewed in detail, while areas such as reading, problem-solving and decision making are viewed from the perspective of memory and learning. Parts of the reference material are drawn from other areas than cognitive psychology: For example, educational psychology and the neurosciences. A total of 513 papers are reviewed of which 360 papers are of Scandinavian origin. On the basis of the reviewed material, three trends are projected: Cognitive task analysis, cognitive neuropsychology and, finally, an increase of qualitative data analyses.     

F. Hegelmaier: On memory for the length of a line

Summary A very early student project undertaken by Friedrich Hegelmaier (1833–1906), published in German in 1852, is republished in English translation. Slight though the experimental work is, it nevertheless occupies a unique place in the history of experimental psychology. It is the source whence Fechner had the method of constant stimuli, a method that continued in use as the preferred psychophysical method, substantially in the form described here, for more than a century. The experiment is arguably the first experiment in the modern sense of a systematic preplanned body of observations and has the glaring faults that one would expect in a very first experiment. Finally, Hegelmaier suggests the use of two simultaneous tasks as a means to investigate human performance, a full hundred years before that idea was realized in practice. If only he had continued in experimental psychology!     

Person perception and the bounded rationality of social judgment

In this article, we develop a bounded rationality view of the relation between person perception and social behavior. Two theses of this approach are that behaviors vary in their significance to observers, and that observers pursue bounded rather than global utility in forming personality impressions. Observers are expected to be sensitive to targets' overall behavioral tendencies and to the variability of their behavior across situations, but both sensitivities are bounded, being greater for behaviors that directly affect observers' outcomes. In two investigations involving extensive hourly and 6-s observations, we examined the bounded utility of people's impressions of personality, demonstrating how impression accuracy is linked to the significance of behaviors. Observers were sensitive to the organization of aggressive behaviors, but less sensitive to the organization of withdrawn behaviors, even when the consistency of those behaviors was comparable. The results clarify the relation between people's inferential shortcomings in laboratory paradigms and the bounded utility of person perception in the natural environment.     

Attention shifts and memory averaging

When observers are asked to localize the final position of a moving stimulus, judgements may be influenced by additional elements that are presented in the visual scene. Typically, judgements are biased toward a salient non-target element. It has been assumed that the non-target element acts as a landmark and attracts the remembered final target position. The present study investigated the effects of briefly flashed non-target elements on localization performance. Similar to landmark attraction, localization was biased toward these elements. However, an influence was only noted if the distractor was presented at the time of target disappearance or briefly thereafter. It is suggested that memory traces of distracting elements are only averaged with the final target position if they are highly activated at the time the target vanishes.     

Hypothesis generation,probability judgment,and individual differences in working memory capacity

This research examined the role of working memory (WM) in probability judgment and hypothesis generation using a simulated task that involved estimating the likelihood that particular menu items would be ordered by customers at a dinner. Five main findings were observed. First, judgments of the likelihood of individual items were made relative to alternatives retrieved from long-term memory. Second, the number of alternatives retrieved was positively correlated with a measure of WM-capacity (the operation-span task). Third, participants' probability judgments were subadditive (summing to well over 100%). Fourth, the degree to which participants' judgments were subadditive was affected by the number and strength of the alternatives retrieved from long-term memory. Fifth, the degree to which participants were subadditive was negatively correlated with WM-capacity. The results suggest that individual differences in WM-capacity are fundamental to hypothesis generation and probability judgment.     

Electrophysiological difference between the representations of causal judgment and associative judgment in semantic memory

Causally related concepts like “virus” and “epidemic” and general associatively related concepts like “ring” and “emerald” are represented and accessed separately. The Evoked Response Potential (ERP) procedure was used to examine the representations of causal judgment and associative judgment in semantic memory. Participants were required to remember a task cue (causal or associative) presented at the beginning of each trial, and assess whether the relationship between subsequently presented words matched the initial task cue. The ERP data showed that an N400 effect (250–450 ms) was more negative for unrelated words than for all related words. Furthermore, the N400 effect elicited by causal relations was more positive than for associative relations in causal cue condition, whereas no significant difference was found in the associative cue condition. The centrally distributed late ERP component (650–750 ms) elicited by the causal cue condition was more positive than for the associative cue condition. These results suggested that the processing of causal judgment and associative judgment in semantic memory recruited different degrees of attentional and executive resources.     

Attention switching and working memory spans

Barrouillet and Camos () concluded from their developmental study on working memory that when performing complex span tasks, individuals maintain memory items by switching rapidly their attention from processing to storage while performing the concurrent task. Thus, a processing component that would require a continuous attentional focusing should have a highly detrimental effect on span. The present study verifies two predictions issuing from this hypothesis by comparing the classical self‐paced reading and operation span tasks with new computer‐paced tasks in adults. First, any increase in the pace at which the processing component of a working memory span task has to be performed impedes switching and then leads to lower spans. Second, when presented at a fast pace, even simple activities such as reading letters or adding and subtracting 1 to small numbers have an effect on spans as detrimental as complex activities like reading and understanding sentences or solving complex equations.