Electrophysiological evidence for dissociable processes contributing to recollection

This paper reviews a number of studies in which we have employed event-related potentials (ERPs) to investigate the cognitive processes which contribute to conscious recollection. Across a range of tasks (including recognition memory, source memory, associative recall and word-stem cued recall) there is evidence for the proposal that recollection involves processes which are both functionally and neurologically dissociable. This evidence takes the form of temporally and topographically dissociable ERP effects, which attain their maximum amplitude when elicited by items that satisfy operational definitions for having been recollected. The ERP effects are interpreted as reflecting retrieval and post-retrieval processes which, we argue, constitute two separate components of recollection as defined within the process dissociation framework of Jacoby and colleagues. The ERP findings suggest that post-retrieval processing is particularly sensitive to task variables, implying that recollection may be neither functionally nor neurologically homogeneous.     

Electrophysiological evidence on the time course of semantic and phonological processes in speech production.

The temporal properties of semantic and phonological processes in speech production were investigated in a new experimental paradigm using movement-related brain potentials. The main experimental task was picture naming. In addition, a 2-choice reaction go/no-go procedure was included, involving a semantic and a phonological categorization of the picture name. Lateralized readiness potentials (LRPs) were derived to test whether semantic and phonological information activated motor processes at separate moments in time. An LRP was only observed on no-go trials when the semantic (not the phonological) decision determined the response hand. Varying the position of the critical phoneme in the picture name did not affect the onset of the LRP but rather influenced when the LRP began to differ on go and no-go trials and allowed the duration of phonological encoding of a word to be estimated. These results provide electrophysiological evidence for early semantic activation and later phonological encoding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Categorization processes in mental comparisons.

Five experiments explore categorization and category-based congruity effects in mental comparisons. The first 4 experiments concentrate on categorization of infinite-set small items. The experiments vary the additional items presented and whether those items appear once (Experiments 1-2) or repeatedly (Experiments 3-4). Additional items include other small items (Experiment 1), relatively large items (Experiments 2-4), and items involving nonsize dimensions (Experiment 4). The critical small items show a complete congruity effect only in Experiments 1 and 3. Results suggest that categorization of infinite-set items may be based on range information alone (Experiment 1) but that multiple categorizations based on multiple ranges (Experiment 2) may require attentional effort. Results implicate categorization as a central process in mental comparison, despite differences in ease of categorization across paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

No evidence for temporal decay in working memory.

What drives forgetting in working memory? Recent evidence suggests that in a complex-span task in which an irrelevant processing task alternates with presentation of the memoranda, recall declines when the time taken to complete the processing task is extended while holding the time for rehearsal in between processing steps constant (Portrat, Barrouillet, & Camos, 2008). This time-based forgetting was interpreted in support for the role of time-based decay in working memory. In this article, we argue the contrary position by (a) showing in an experiment that the processing task in Portrat et al.’s (2008) study gave rise to uncontrolled post-error processes that occupied the attentional bottleneck, thus preventing restorative rehearsal, and (b) showing that when those post-error processes are statistically controlled, there is no evidence for temporal decay in Portrat et al.’s study. We conclude that currently there exists no direct evidence for temporal decay in the complex-span paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ironic processes of mental control.

A theory of ironic processes of mental control is proposed to account for the intentional and counterintentional effects that result from efforts at self-control of mental states. The theory holds that an attempt to control the mind introduces 2 processes: (1) an operating process that promotes the intended change by searching for mental contents consistent with the intended state and (2) a monitoring process that tests whether the operating process is needed by searching for mental contents inconsistent with the intended state. The operating process requires greater cognitive capacity and normally has more pronounced cognitive effects than the monitoring process, and the 2 working together thus promote whatever degree of mental control is enjoyed. Under conditions that reduce capacity, however, the monitoring process may supersede the operating process and thus enhance the person's sensitivity to mental contents that are the ironic opposite of those that are intended. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological processes and mental states.

Comments on D. Kipnis's (see record 199707781-001) article that argues against the use of psychological processes as a basis for the explanation of social behavior. The present author concerns himself with Kipnis's use of "psychological processes" and "mental states" as synonyms. He claims that Kipnis overstepped his argument by generalizing his conclusion from the term "mental states" to "psychological processes." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electrophysiological evidence for a shared representational medium for visual images and visual percepts.

Systematic effects of imagery on visual signal detection performance have been used to argue that imagery and the perceptual processing of stimuli interact at some common locus of activity (Farah, 1985). However, such a result is neutral with respect to the question of whether the interaction occurs during modality-specific visual processing of the stimulus. If imagery affects stimulus processing at early, modality-specific stages of stimulus representation, this implies that the shared stimulus representations are visual, whereas if imagery affects stimulus processing only at later, amodal stages of stimulus representation, this implies that imagery involves more abstract, postvisual stimulus representations. To distinguish between these 2 possibilities, we repeated the earlier imagery-perception interaction experiment while recording event-related potentials (ERPs) to stimuli from 16 scalp electrodes. By observing the time course and scalp distribution of the effect of imagery on the ERP to stimuli, we can put constraints on the locus of the shared representations for imagery and perception. An effect of imagery was seen within 200 ms following stimulus presentation, at the latency of the 1st negative component of the visual ERP, localized at the occipital and posterior temporal regions of the scalp, that is, directly over visual cortex. This finding supports the claim that mental images interact with percepts in the visual system proper and hence that mental images are themselves visual representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electrophysiological evidence for the "missing link" in crossmodal attention.

Notes that orienting attention involuntarily to the location of a sensory event influences responses to subsequent stimuli that appear in different modalities with one possible exception; orienting attention involuntarily to a sudden light sometimes fails to affect responses to subsequent sounds (e.g., C. Spence and J. Driver, 1997). Here the authors investigated the effects of involuntary attention to a brief flash on the processing of subsequent sounds in a design that eliminates stimulus–response compatibility effects and criterion shifts as confounding factors. 13 18–31 yr olds participated in the study. In addition, the neural processes mediating crossmodal attention were studied by recording event-related brain potentials. The data show that orienting attention to the location of a spatially nonpredictive visual cue modulates behavioral and neural responses to subsequent auditory targets when the stimulus onset asynchrony is short (between 100 and 300 ms). These findings are consistent with the hypothesis that involuntary shifts of attention are controlled by supramodal brain mechanisms rather than by modality-specific ones. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Queueing network modeling of elementary mental processes.

This article examines the use of reaction time (RT) to infer the possible configurations of mental systems and presents a class of queueing network models of elementary mental processes. The models consider the temporal issue of discrete versus continuous information transmission in conjunction with the architectural issue of serial versus network arrangement of mental processes. Five elementary but important types of queueing networks are described in detail with regard to their predictions for RT behavior, and they are used to re-examine existing models for psychological processes. As continuous-transmission networks in the general form, queueing network models include the existing discrete and continuous serial models and discrete network models as special cases, cover a broader range of temporal and architectural structures that mental processes might assume, and can be subjected to empirical tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Electrophysiological and behavioral evidence of syntactic priming in sentence comprehension.

Event-related potentials and eye tracking were used to investigate the nature of priming effects in sentence comprehension. Participants read 2 sentences (a prime sentence and a target sentence), both of which had a difficult and ambiguous sentence structure. The prime and target sentences contained either the same verb or verbs that were very close in meaning. Priming effects were robust when the verb was repeated. In the event-related potential experiment, the amplitude of the P600 was reduced in target sentences that followed prime sentences with the same verb but not in prime sentences with a synonymous verb. In the eye-tracking experiment, total reading times on the disambiguating region were reduced when the targets followed prime sentences with the same verb but not when targets followed prime sentences with a synonymous verb. The fact that verb overlap greatly boosted priming effects in reduced relative sentences may indicate that verb argument structures play an important role in online parsing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the temporal dynamics of digit comparison processes.

The authors studied the temporal dynamics of digit comparison processes by presenting the digits with a stimulus onset asynchrony (SOA) of 0, 70, 140, or 210 ms. Experiment 1 used the standard complete paired comparison design that confounds numerical and probabilistic information in the digit presented first. The results showed large effects of SOA that differed characteristically for different digit pairs. These results changed considerably in Experiment 2, using a design that removed any probabilistic contingencies. Experiment 3 examined a form of congruity effect related to the temporal order of the digits. The authors formulated and compared to the data 2 models that differed in their assumptions about the loci of digit-specific and SOA-specific effects: Either the participants use partial numerical advance information to prepare for the suggested response, or they start to process numerical information only after both digits are presented. When probabilistic contingencies were removed, the data favored the latter model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychophysical evidence for a shared representational medium for mental images and percepts.

The intuition that imagery is similar to perception has led many psychologists to assume that imaging an object consists of activating some of the same representational structures that are activated during the perception of that object. This assumption was tested in 2 experiments with 23 undergraduates by measuring the effects of visual imagery on concurrent visual perception. The experimental task consisted of a 2-interval forced-choice detection task (no stimulus identification required) during which the S imaged a particular stimulus. In Exp I, a matching image led to better detection than a nonmatching image. Interactions between imagery and perception implied a common locus of activity, and the content-specific interactions obtained implied that the common locus consisted of representational structures. In Exp II, a matching image facilitated perception only when the image and the stimulus were in the same position, suggesting that the shared representational structures occurred at an analog level of perceptual representation. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preserved monitoring and control processes in temporal lobe epilepsy.

Objective: The aim of this study was to assess an aspect of metamemory never examined before in patients with temporal lobe epilepsy (TLE): the ability to upgrade the accuracy of one's memory predictions after study. Method: Four lists of different levels of difficulty and relatedness were presented to 15 TLE patients and 15 control participants, who were asked to predict their subsequent recall both before and after studying each list. Results: The results showed clear impairment in recall in TLE patients. However, both TLE patients and controls showed an improvement in accuracy in their poststudy predictions compared with their prestudy predictions, showing that both groups were able to upgrade their metamemory predictions. Unexpectedly, prediction accuracy was overall higher in TLE patients than in controls. Moreover, study time was allocated in both groups taking into account the characteristics of the list. Conclusion: These results confirm and extend findings of Howard et al. (2010) of intact metamemory in TLE patients, and provide further support to the dissociation between memory and metamemory in this clinical population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Basic behavioral science research for mental health: Sociocultural and environmental processes.

Provides a selective overview of sociocultural research investigating the role of culture in the course of mental illness and suggests promising directions for future research. Sociocultural variation in basic psychological processes and experiences including identity, self-esteem, attribution, and motivation are discussed. The role of race, ethnicity, SES, changing work roles, and communities in mental health across the life span are also explored. Possible directions for future research include cross-cultural research on universal vs culturally specific aspects of behavior, the expression and effects of ethnic discrimination, and factors mediating the effects of SES on the mental health of children and adults (0 ref). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of temporal overlap of visual and auditory material in forming dual media associations.

Examined the role of contiguity in forming associations between the visual and spoken material in a dual-media presentation such as a film or videotape. 14 groups of 24 college students each were shown a 30-min film that introduced an assembly kit, its pieces, their names, and some of their uses. The film's visual and narrative components could be presented in synchrony, or one could be shifted relative to the other by as much as 21 sec. Ss saw the film in 1 or 7 versions: visuals presented 21, 14, or 7 sec before narration; in synchrony with narration; or 7, 14, or 21 sec after narration. They were tested immediatedly or after 7 days for recall of the names given the pieces. Scores were highest immediately and after 7 days for 2 groups: the synchrony group and the group shown visuals 7 sec before narration. On the immediate test, the scores for each of the other 5 groups were about 80% those of the highest groups. On the test after 7 days, the other 5 groups scored slightly though not significantly differently: The 3 narration-first groups performed about 30% less well than did the 2 visuals-first groups. The temporal order in which visual and auditory elements were presented differentially influenced the formation of dual-media associations. When auditory elements preceded visual elements, much of the auditory component was lost. Three possible theoretical interpretations are given. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Making time count: Functional evidence for temporal coding of taste sensation.

Although the temporal characteristics of neural responses have been proposed as a mechanism for sensory neural coding, there has been little evidence thus far that this type of information is actually used by the nervous system. Here the authors show that patterned electrical pulses trains that mimic the response to the taste of quinine can produce a bitterlike sensation when delivered to the nucleus tractus solitarius of behaving rats. Following conditioned aversion training using either "quinine simulation" patterns of electrical stimulation or natural quinine (0.1 mM) as a conditioned stimulus, rats specifically generalized the aversion to 2 bitter tastants: quinine and urea. Randomization of the quinine simulation patterns resulted in generalization patterns that resembled those to a perithreshold concentration (0.01 mM) of quinine. These data provide strong evidence that the temporal pattern of brainstem activity may convey information about taste quality and underscore the functional significance of temporal coding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aging and involuntary attention capture: Electrophysiological evidence for preserved attentional control with advanced age.

The present study examined whether people become more susceptible to capture by salient objects as they age. Participants searched a target display for a letter in a specific color and indicated its identity. In Experiment 1, this target display was preceded by a non-informative cue display containing one target-color box, one ignored-color box, and two white boxes. On half of the trials, this cue display also contained a salient-but-irrelevant abrupt onset. To assess capture by the target-color cue, we used the N2pc component of the event-related potential, thought to reflect attentional allocation to the left or right visual field. The target-color box in the cue display produced a substantial N2pc effect for younger adults and, most importantly, this effect was not diminished by the presence of an abrupt onset. Therefore, the abrupt onset was unable to capture attention away from the target-color cue. Critically, older adults demonstrated the same resistance to capture by the abrupt onset. Experiment 2 extended these findings to irrelevant color singleton cues. Thus, we argue that the ability to attend to relevant stimuli and resist capture by salient-but-irrelevant stimuli is preserved with advancing age. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Abortion and mental health: Evaluating the evidence.

The authors evaluated empirical research addressing the relationship between induced abortion and women’s mental health. Two issues were addressed: (a) the relative risks associated with abortion compared with the risks associated with its alternatives and (b) sources of variability in women’s responses following abortion. This article reflects and updates the report of the American Psychological Association Task Force on Mental Health and Abortion (2008). Major methodological problems pervaded most of the research reviewed. The most rigorous studies indicated that within the United States, the relative risk of mental health problems among adult women who have a single, legal, first-trimester abortion of an unwanted pregnancy is no greater than the risk among women who deliver an unwanted pregnancy. Evidence did not support the claim that observed associations between abortion and mental health problems are caused by abortion per se as opposed to other preexisting and co-occurring risk factors. Most adult women who terminate a pregnancy do not experience mental health problems. Some women do, however. It is important that women’s varied experiences of abortion be recognized, validated, and understood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contributions of prefrontal cortex to recognition memory: Electrophysiological and behavioral evidence.

To clarify the involvement of prefrontal cortex in episodic memory, behavioral and event-related potential (ERP) measures of recognition were examined in patients with dorsolateral prefrontal lesions. In controls, recognition accuracy and the ERP old–new effect declined with increasing retention intervals. Although frontal patients showed a higher false-alarm rate to new words, their hit rate to old words and ERP old–new effect were intact, suggesting that recognition processes were not fundamentally altered by prefrontal damage. The opposite behavioral pattern was observed in patients with hippocampal lesions: a normal false-alarm rate and a precipitous decline in hit rate at long lags. The intact ERP effect and the change in response bias during recognition suggest that frontal patients exhibited a deficit in strategic processing or postretrieval monitoring, in contrast to the more purely mnemonic deficit shown by hippocampal patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The perception of temporal order along the mental number line.

R. Sekuler, P. Tynan, and E. Levinson (1973) found that when 2 characters are presented side-by-side with a short onset asynchrony, subjectively they often appear in a “first-left, then-right” order. The authors of this article conducted 6 experiments in which observers judged the temporal order (TOJs) in which 2 digits were presented. They found a consistent TOJ benefit (larger d`) when the numerically smaller digit was presented first, even though this semantic information was irrelevant to the task and unrelated to the correct response. They concluded that digits located to the left of the mental number line are transmitted faster to a central comparison stage, which represents an “internal counterpart” to the Sekuler et al. (1973) finding regarding external locations. A corresponding benefit is found for letters pairs (e.g., A–Z) and also for mixed digit–letter pairs (e.g., 1–Z). (PsycINFO Database Record (c) 2010 APA, all rights reserved)