The chronometry of single neuron activity: testing discrete and continuous models of information processing

The authors propose to study information transmission by comparing the effects of experimental factors on reaction time (RT) with the latency of the changes in activity of single-neurons. An experiment was conducted in which a monkey (Macaca mulatta) performed a tactilo-manual 2-choice RT task and the compatibility of the stimulus-response mapping was manipulated. Task-related neurons were recorded in the monkey's primary somesthetic and motor cortices. The changes in activity of 105 of these neurons were classified either as sensory-like or as motor-like. The sensory-like changes occurred before the motor-like ones. The stimulus-response mapping exerted its entire effect on the RT after the sensory-like changes and before the motor-like ones. These findings suggest that the information was transmitted discretely from the processes affected by the mapping to the processes implemented by the motor-like changes.     

Partial advance information,number of alternatives,and motor processes: an electromyographic study

We present evidence that advance information reducing the number of stimulus-response alternatives in a choice reaction time (RT) task can shorten the very latest motoric stages of RT. Effects of such advance information on late stages of RT have been demonstrated recently by Osman, Moore, and Ulrich (Acta Psychol. 90 (1995) 111), Leuthold, Sommer, and Ulrich (J. Exp. Psychol: Gen. 125 (1996) 307), Müller-Gethmann, Rinkenauer, Stahl, and Ulrich (Psychophysiology 37 (2000) 507). These studies found that advance information shortens the portion of the RT interval following onset of a movement-related brain potential (lateralized readiness potential). Osman et al. and Müller-Gethmann et al. also examined the portion of the RT interval following the start of electromyographic (EMG) activity and found no effect of advance information. Based on Osman et al.'s null result, Leuthold et al. speculated that advance information may shorten only the RT stages preceding EMG activity. This conclusion, however, is questionable because of limitations in the EMG measures employed by both Osman et al. and Müller-Gethmann et al. We have reanalyzed the results of a previously reported experiment (Acta Psychol. 101 (1999) 243) to show that advance information can in fact affect the rate of recruitment of motor units in the prime mover of the responding limb.     

Implicit processing of tactile information: evidence from the tactile change detection paradigm

People can maintain accurate representations of visual changes without necessarily being aware of them. Here, we investigate whether a similar phenomenon (implicit change detection) also exists in touch. In Experiments 1 and 2, participants detected the presence of a change between two consecutively-presented tactile displays. Tactile change blindness was observed, with participants failing to report the presence of tactile change. Critically, however, when participants had to make a forced choice response regarding the number of stimuli presented in the two displays, their performance was significantly better than chance (i.e., implicit change detection was observed). Experiment 3 demonstrated that tactile change detection does not necessarily involve a shift of spatial attention toward the location of change, regardless of whether the change is explicitly detected. We conclude that tactile change detection likely results from comparing representations of the two displays, rather than by directing spatial attention to the location of the change.     

Controlled information processing resources and the development of automatic detection responses in schizophrenia

The relation between resource limitations and the type of processing (automatic vs. controlled) on a multiple-frame search task (MFST) was examined in 15 schizophrenic and 15 normal control subjects. After 320 trials of consistently mapped practice, the patients' detection accuracy was normalized, and the effect of processing load (letter array size) on their detection accuracy was eliminated, which suggests automatization. Changes in load effects with practice could not be used as an index of automatization in control subjects, because of their unexpected lack of load effects at the beginning of practice. In a dual-task (MFST during auditory shadowing) condition after MFST practice, patients' MFST accuracy deteriorated nonsignificantly, and patients' shadowing declined significantly. The findings suggest schizophrenics have reduced available processing resources, but research is needed to determine whether this is due to abnormal automatization.     

Acute aerobic exercise and information processing: energizing motor processes during a choice reaction time task

The immediate and short-term after effects of a bout of aerobic exercise on young adults’ information processing were investigated. Seventeen participants performed an auditory two-choice reaction time (RT) task before, during, and after 40 min of ergometer cycling. In a separate session, the same sequence of testing was completed while seated on an ergometer without pedalling. Results indicate that exercise (1) improves the speed of reactions by energizing motor outputs; (2) interacts with the arousing effect of a loud auditory signal suggesting a direct link between arousal and activation; (3) gradually reduces RT and peaks between 15 and 20 min; (4) effects on RT disappear very quickly after exercise cessation; and (5) effects on motor processes cannot be explained by increases in body temperature caused by exercise. Taken together, these results support a selective influence of acute aerobic exercise on motor adjustment stage.     

Effects of mood states on information processing strategies: Two studies of automatic and controlled processing using misattribution paradigms

To test the hypothesis that a positive mood facilitates automatic processing and a negative mood facilitates controlled processing, two experiments were conducted. In Experiment 1, after positive or negative mood was induced, participants rated the attractiveness of products while listening to a music tape that they were told would have the effect of inducing a positive, negative, or neutral mood. As predicted, augmentation effects were clearer in the negative mood condition than in the positive mood condition. In Experiment 2, participants were first presented with lists of names of non-famous Japanese companies either once or four times. One or two days later, they were presented with these names again, together with new names, and were asked to judge whether those names were famous or-non-famous. As predicted, subjects in a positive mood showed more false fame judgments than those in a negative mood because those in a positive mood did not control their feeling of familiarity correctly. These results indicated that those in positive moods are more likely to engage in automatic processing.     

Results of electroencephalographic and familial studies in Wilson's disease]

The results of electroencephalographic and familial studies of 31 Wilson's disease patients coming from 26 kindreds are presented. Prior to treatment, 8 patients showed pathological conditions, while 9 and 11 patients showed borderline and normal conditions, respectively, it having not been possible to determine electroencephalographic conditions characteristic of Wilson's disease and find any relationships between the intensity of E.E.G. changes and the clinical picture and stage of development of the disease, respectively. Under penicillamine treatment, there was observed a tendency toward normalization of pathological conditions rather than deterioration of normal E.E.G. findings. So far as familial studies are concerned, the authors report the results obtained for 9 fathers, 19 mothers, and 24 siblings from a total of 21 kindreds; what is remarkable in this connection is the comparatively small percentage of normal E.E.G. findings for healthy siblings. It was only in one single kindred that it was possible to observe similarities between E.E.G. variations of individual family members.     

Motivated information processing and group decision-making: Effects of process accountability on information processing and decision quality

Integrating dual-process models [Chaiken, S., & Trope, Y. (Eds.). (1999). Dual-process theories in social psychology. NewYork: Guilford Press] with work on information sharing and group decision-making [Stasser, G., & Titus, W. (1985). Pooling of unshared information in group decision making: biased information sampling during discussion. Journal of Personality and Social Psychology, 48, 1467-1478.], we predicted that groups with high epistemic motivation engage in more information-driven and less preference-driven interaction, and achieve better decisions. An experiment manipulating process accountability showed that groups under process accountability experienced greater need for more information, repeated unshared information more often, and more often chose the correct decision alternative. Mediation analysis established that epistemic motivation produced high quality decisions because it stimulated systematic information processing. Results also revealed that preference heterogeneity stimulated information-driven interaction and led to higher decision quality.     

Cardiac activity and information processing: the effects of stimulus significance, and detection and response requirements.

In two experiments, measures of heart rate and electromyographic activity were obtained from 40 male undergraduates while they performed two series of trials involving a sequential information processing task. Each trial consisted of a warning light, three successive tones, and a responded light, separated by 6-sec intervals. In Experiment 1, subjects responded only if the three tones were of different frequencies. Acclerative heart-rate responses to the last tone increased as a function of the significance of that tone. Subsequent cardiac decelerations were only observed if the subject was preparing to make a response. These results were replicated in Experiment 2, in which subjects responded only if two of the preceding tones were of the same frequency. Electromyographic activity was not significantly affected by stimulus significance or response anticipation. The data indicate that cardiac acceleration and deceleration reflect two independent psychological processes, associated with information-processing and decision-making activity on the one hand, and preparatory activity on the other.     

Promoting systematic processing in low-motivation settings: effect of incongruent information on processing and judgment

Ss received consensus information that was either congruent or incongruent with the valence of persuasive message content. In Experiment 1 Ss believed that their processing task was either important or unimportant whereas in Experiment 2 all Ss believed that their task was unimportant. In accord with the heuristic-systematic model's sufficiency principle, high-task-importance Ss exhibited a great deal of systematic processing regardless of congruency, whereas low-importance Ss processed systematically only when they received incongruent messages; in the congruent conditions heuristic processing dominated. Attitude data generally reflected these processing differences and confirmed the additivity and attenuation assumptions of the model. The utility of the sufficiency principle for understanding motivation for elaborative processing and the relevance of the findings to understanding the processing and judgmental effects of expectancy disconfirmation are discussed.     

Gestalt and feature-intensive processing: Toward a unified model of human information processing

“Cognitive asynchrony theory,” recently developed in research on aging and memory, implies a functional distinction between the processing of “feature-intensive” items, those with numerous identifiable features, and the processing of images which are relatively sparse in such features and are handled in a more wholistic, “gestalt” manner. The present experiments addressed the question of whether such a distinction exists outside the realms of memory in which it has thus far been addressed. The present work used mental rotation as a model system. Consistent with the predictions of this model, Experiment 1 showed that feature-intensive figures required significantly more time to rotate than did gestalt figures, even though angles of rotation were the same. Experiment 2 demonstrated that feature-intensive processing may involve verbally-accessible semantic systems to a greater degree than is the case with “gestalt” items. Experiment 3 identified significant practice effects of feature-intensive stimuli on the processing of gestalt stimuli, but not the reverse. The results of these experiments indicate that the “gestalt/feature-intensive” processing distinction extends to mental rotation as well as to memory. Implications for the nature of mental representation of verbal and visual materials are discussed.     

Gestalt and feature-intensive processing: Toward a unified model of human information processing

“Cognitive asynchrony theory,” recently developed in research on aging and memory, implies a functional distinction between the processing of “feature-intensive” items, those with numerous identifiable features, and the processing of images which are relatively sparse in such features and are handled in a more wholistic, “gestalt” manner. The present experiments addressed the question of whether such a distinction exists outside the realms of memory in which it has thus far been addressed. The present work used mental rotation as a model system. Consistent with the predictions of this model, Experiment 1 showed that feature-intensive figures required significantly more time to rotate than did gestalt figures, even though angles of rotation were the same. Experiment 2 demonstrated that feature-intensive processing may involve verbally-accessible semantic systems to a greater degree than is the case with “gestalt” items. Experiment 3 identified significant practice effects of feature-intensive stimuli on the processing of gestalt stimuli, but not the reverse. The results of these experiments indicate that the “gestalt/feature-intensive” processing distinction extends to mental rotation as well as to memory. Implications for the nature of mental representation of verbal and visual materials are discussed.     

Development and validation of the social information processing application: a Web-based measure of social information processing patterns in elementary school-age boys

The purpose of this study was to evaluate the psychometric properties of an audio computer-assisted self-interviewing Web-based software application called the Social Information Processing Application (SIP-AP) that was designed to assess social information processing skills in boys in 3rd through 5th grades. This study included a racially and ethnically diverse sample of 244 boys ages 8 through 12 (M = 9.4) from public elementary schools in 3 states. The SIP-AP includes 8 videotaped vignettes, filmed from the first-person perspective, that depict common misunderstandings among boys. Each vignette shows a negative outcome for the victim and ambiguous intent on the part of the perpetrator. Boys responded to 16 Web-based questions representing the 5 social information processing mechanisms, after viewing each vignette. Parents and teachers completed measures assessing boys' antisocial behavior. Confirmatory factor analyses revealed that a model positing the original 5 cognitive mechanisms fit the data well when the items representing prosocial cognitions were included on their own factor, creating a 6th factor. The internal consistencies for each of the 16 individual cognitions as well as for the 6 cognitive mechanism scales were excellent. Boys with elevated scores on 5 of the 6 cognitive mechanisms exhibited more antisocial behavior than boys whose scores were not elevated. These findings highlight the need for further research on the measurement of prosocial cognitions or cognitive strengths in boys in addition to assessing cognitive deficits. Findings suggest that the SIP-AP is a reliable and valid tool for use in future research of social information processing skills in boys.     

Biased information processing in the escalation paradigm: information search and information evaluation as potential mediators of escalating commitment

Escalation of commitment denotes decision makers' increased reinvestment of resources in a losing course of action. Despite the relevance of this topic, little is known about how information is processed in escalation situations, that is, whether decision makers who receive negative outcome feedback on their initial decision search for and/or process information biasedly and whether these biases contribute to escalating commitment. Contrary to a widely cited study by E. J. Conlon and J. M. Parks (1987), in 3 experiments, the authors found that biases do not occur on the level of information search. Neither in a direct replication and extension of the original study with largely increased test power (Experiment 1) nor under methodologically improved conditions (Experiments 2 and 3) did decision makers responsible for failure differ from nonresponsible decision makers with regards to information search, and no selective search for information supporting the initial decision or voting for further reinvestment was observed. However, Experiments 3 and 4 show that the evaluation of the previously sought information is biased among participants who were responsible for initiating the course of action. Mediation analyses show that this evaluation bias in favor of reinvestment partially mediated the responsibility effect on escalation of commitment.     

An eye‐tracking study on information processing in risky decisions: Evidence for compensatory strategies based on automatic processes

Many everyday decisions have to be made under risk and can be interpreted as choices between gambles with different outcomes that are realized with specific probabilities. The underlying cognitive processes were investigated by testing six sets of hypotheses concerning choices, decision times, and information search derived from cumulative prospect theory, decision field theory, priority heuristic and parallel constraint satisfaction models. Our participants completed 40 decision tasks of two gambles with two non‐negative outcomes each. Information search was recorded using eye‐tracking technology. Results for choices, decision time, the amount of information searched for, fixation durations, the direction of the information search, and the distribution of fixations conflict with the prediction of the non‐compensatory priority heuristic and indicate that individuals use compensatory strategies. Choice proportions are well in line with the predictions of cumulative prospect theory. Process measures indicate that individuals thereby do not rely on deliberate calculations of weighted sums. Information integration processes seem to be better explained by models that partially rely on automatic processes such as decision field theory or parallel constraint satisfaction models. Copyright © 2010 John Wiley & Sons, Ltd.     

Attitudinal ambivalence and message-based persuasion: motivated processing of proattitudinal information and avoidance of counterattitudinal information

Attitudinal ambivalence has been found to increase processing of attitude-relevant information. In this research, the authors suggest that ambivalence can also create the opposite effect: avoidance of thinking about persuasive messages. If processing is intended to reduce experienced ambivalence, then ambivalent people should increase processing of information perceived as proattitudinal (agreeable) and able to decrease ambivalence. However, ambivalence should also lead people to avoid processing of counterattitudinal (disagreeable) information that threatens to increase ambivalence. Three studies provide evidence consistent with this proposal. When participants were relatively ambivalent, they processed messages to a greater extent when the messages were proattitudinal rather than counterattitudinal. However, when participants were relatively unambivalent, they processed messages more when the messages were counterattitudinal rather than proattitudinal. In addition, ambivalent participants perceived proattitudinal messages as more likely than counterattitudinal messages to reduce ambivalence, and these perceptions accounted for message position effects on amount of processing.