Can associative information be strategically separated from item information in word-pair recognition?

Subjects learned word pairs either once or three times but were instructed to ignore the association of the two words in each pair and only to memorize the individual words at study and recognize them at test. The test word pairs included intact pairs, rearranged pairs made up of old words exchanged among the studied pairs, and new pairs consisting of one old and one new word. Subjects were instructed to respond yes to both intact and rearranged pairs and no to new pairs. Results showed that the rearranged test pairs, as compared with intact pairs, produced longer reaction times, lower discrimination (d′), and lower remember judgments. In addition, more learning either did not reduce or actually increased the pairing effect. These results are difficult to reconcile with the notion that associative information is retrieved in a slow, controlled, and effortful process but are consistent with the encoding specificity principle and the global activation theory of recognition.     

Can semantic information be transferred between hemispheres in the split-brain?

Data from experiments with split-brain patients, who have had their left and right hemispheres disconnected, suggests a remarkable specialization of function within each hemisphere. At the same time, these patients conduct their daily lives with great proficiency. This ability suggests that some information integral to coordinated function between the hemispheres is available in the absence of the corpus callosum. Is information about the semantics of words one type of information that is shared? An experiment by suggests that it may be. Lambert reported that living/nonliving word categorization was delayed when disconnected hemispheres processed words belonging to the same category. Although other interpretations are plausible, Lambert described this effect as having a semantic source. We attempted to replicate the original effect with two additional split-brain patients, J.W. and V.P., and to extend the original design to clarify the source of the putative semantic effect. Our results indicate that any semantic interaction between the split hemispheres is not reliable. As such our study adds to the growing literature indicating that subcortical transfer of semantic information is more illusory than real.     

Can expectancies produce placebo effects for implicit learning?

The placebo effect is an important phenomenon whereby real changes occur in response to an otherwise inert intervention. Despite increasing research attention, it remains unclear exactly which processes are amenable to placebo effects. The current study tested whether an instructional manipulation could produce placebo effects on a nonconscious cognitive task, namely implicit learning. Four hundred and sixty-four university students completed a visual search task while smelling an odor or no odor, in alternating blocks. Unknown to them, the task contained a contingency whereby on half the trials the target's location was cued by the pattern of distractors, which was achieved by repeating some configurations of targets and distractors. Prior to the task, participants received positive, negative, or no information about the odor's possible effects on performance. Those given positive information demonstrated faster reaction times on cued trials than other participants. Those given negative information showed slower reaction times on cued trials compared with participants given no information. Further, the cuing effect appeared to be nonconscious, with participants' ability to recognize the repeated configurations equivalent to chance and no evidence that performance on a recognition test was related to the magnitude of the cuing effect. This suggests that instructional manipulations can produce placebo effects on some nonconscious processes.     

Readers’ use of source information in text comprehension

In two experiments, we examined the role of discrepancy on readers’ text processing of and memory for the sources of brief news reports. Each story included two assertions that were attributed to different sources. We manipulated whether the second assertion was either discrepant or consistent with the first assertion. On the basis of the discrepancy-induced source comprehension (D-ISC) assumption, we predicted that discrepant stories would promote deeper processing and better memory for the sources conveying the messages, as compared to consistent stories. As predicted, readers mentioned more sources in summaries of discrepant stories, recalled more sources, made more fixations, and displayed longer gaze times in source areas when reading discrepant than when reading consistent stories. In Experiment 2, we found enhanced memory for source–content links for discrepant stories even when intersentential connectors were absent, and regardless of the reading goals. Discussion was focused on discrepancies as one mechanism by which readers are prompted to encode source–content links more deeply, as a method of integrating disparate pieces of information into a coherent mental representation of a text.     

Perirhinal cortex lesions produce retrograde amnesia for spatial information in rats: consolidation or retrieval?

Several lines of evidence in humans and experimental animals suggest that the hippocampus is critical for the formation and retrieval of spatial memory. However, although the hippocampus is reciprocally connected to adjacent cortices within the medial temporal lobe and they, in turn, are connected to the neocortex, little is known regarding the function of these cortices in memory. Here, using a reference spatial memory task in the radial maze, we show that neurotoxic perirhinal cortex lesions produce a profound retrograde amnesia when learning-surgery intervals of 1 or 50 d are used (Experiment 1). With the aim of dissociating between consolidation and retrieval processes, we injected lidocaine either daily after training (Experiment 2) or before a retention test once the learning had been completed (Experiment 3). Results show that reversible perirhinal inactivation impairs retrieval but not consolidation. However, the same procedure followed in Experiment 2 disrupted consolidation when the lidocaine was injected into the dorsal hippocampus. The results of Experiment 4 rule out the possibility that the deficit in retrieval is due to a state-dependent effect. These findings demonstrate the differential contribution of various regions of the medial temporal lobe to memory, suggesting that the perirhinal cortex plays a key role in the retrieval of spatial information for a long period of time.     

Can sample-specific simulations help detect low base-rate taxonicity?

The authors examined the role of the sample-specific simulations (SSS; A. M. Ruscio & J. Ruscio, 2002; J. Ruscio & A. M. Ruscio, 2004) procedure in detecting low base-rate taxa that might otherwise prove elusive. The procedure preserved key distributional characteristics for moderate to high base-rate taxa, but it performed inadequately for low base-rate taxa, with low to moderate nuisance covariance, decreasing indicator validity, and increasing average nuisance covariance. Visual inspection of the curves produced by the SSS procedure, combined with the expectation that the inchworm test should produce a clear peak for low base-rate taxonic samples, led to inappropriate conclusions about the suitability of data. The authors speculate that examination of low base-rate taxa using SSS may require other algorithms for generating comparison distributions, consideration of the shape of the whole curve, and/or relaxation of the expectation that a clear peak will emerge with the inchworm test.     

Are correlated streams of information necessary for implicit sequence learning?

We investigated whether the existence of correlated streams of information is necessary for incidental sequence learning to occur. We ran three separate experiments with a total of 201 undergraduate students. Each experiment had at least one condition with two streams of sequenced information that were correlated. The correlations differed in terms of the kind of responses that were required, the kind of tasks and stimuli, the on-screen locations at which they occurred and how they were combined. Only in conditions with correlated sequences was implicit sequence learning found. Our results suggest that the presence of correlated streams of information may be the main pre-requisite for implicit sequence learning.     

How "implicit" are implicit color effects in memory?

Processing colored pictures of objects results in a preference to choose the former color for a specific object in a subsequent color choice test (Wippich & Mecklenbr?uker, 1998). We tested whether this implicit memory effect is independent of performances in episodic color recollection (recognition). In the study phase of Experiment 1, the color of line drawings was either named or its appropriateness was judged. We found only weak implicit memory effects for categorical color information. In Experiment 2, silhouettes were colored by subjects during the study phase. Performances in both the implicit and the explicit test were good. Selections of "old" colors in the implicit test, though, were almost completely confined to items for which the color was also remembered explicitly. In Experiment 3, we applied the opposition technique in order to check whether we could find any implicit effects regarding items for which no explicit color recollection was possible. This was not the case. We therefore draw the conclusion that implicit color preference effects are not independent of explicit recollection, and that they are probably based on the same episodic memory traces that are used in explicit tests.     

Relations between implicit measures of prejudice:what are we measuring?

Some recent findings suggest that different implicit measures of prejudice assess the same underlying construct, but other work suggests that they may not. In this experiment, White participants completed a version of a priming measure of racial attitudes that either encouraged categorization of the face primes in terms of race or did not encourage such categorization, and then completed the Implicit Association Test. Correspondence between the two measures was found only when categorization by race was required on the priming measure. Moreover, participants appeared more prejudiced when they were led to construe individuals in terms of race than when they were not so encouraged. The discussion focuses on the potential for dissociations between evaluations of a category and evaluations of members of the category.     

What is implicit about implicit self-esteem?

Modern advances in implicit social cognition enabled development of novel methods for examining less conscious aspects of self-worth. The use of such “implicit” measures of self-esteem is based on the premise that because they circumvent direct self-reports, they must capture more implicit, automatic components of self-evaluation. Whether self-evaluations captured via “implicit” measures actually have these functional properties requires empirical verification, however. This investigation critically examined the evidence for such assumptions regarding the Name-Letter Test, one of the most popular implicit measures, by adopting a phenomenological approach. The results revealed that many respondents were aware of the self-relevant nature of the measure at the time of assessment. Moreover, at least some variance in the “implicit” measurement outcomes was accounted for by relevant conscious beliefs, particularly among those aware of the self-relevant nature of the task. The implications for understanding the nature and assessment of unconscious self-worth are discussed.     

Policy information or information policy? information types in economics and policy

The economic distinction between technological and market information offers a useful guide to the relationship between information and policy. The two types create different problems for markets and require different emphases in public policy, focusing on either the production or the distribution of information. The interaction of the two types creates familiar policy problems such as underinvestment in information, adverse selection and moral hazard. Indicators and other means of dealing with such problems constitute policies and demonstrate not only the importance of information for policy but the necessity of policy for information. where he is also affiliated with the Environmental Studies Center. His primary research interests are in public policy, expecially environmental policy and science and technology policy, and in the relationship between policy, economics and information.     

Can third-party observers detect the emotional rewards of generous spending?

Can others detect the emotional consequences of our personal choices? Here, we investigate whether third-party observers can detect the emotional benefits of two factors shown to influence self-reported happiness: the speed with which people make decisions and the generosity of spending choices. Participants were randomly assigned to purchase a goody bag either for themselves or for a sick child, and to choose the contents of this goody bag either as quickly as possible, or by taking as much time as needed. Then, participants reported their current emotional state and were rated for happiness by a research assistant blind to their spending condition. Analyses revealed that purchasing a gift for someone else not only improved participants’ self-reported mood, but that observers could detect these affective differences as well. Observers also rated participants who made their spending decision more quickly as happier, although participants did not report these emotional differences.     

A procedure for evaluating sensitivity to within-person change: can mood measures in diary studies detect change reliably?

The recent growth in diary and experience sampling research has increased research attention on how people change over time in natural settings. Often however, the measures in these studies were originally developed for studying between-person differences, and their sensitivity to within-person changes is usually unknown. Using a Generalizability Theory framework, the authors illustrate a procedure for developing reliable measures of change using a version of the Profile of Mood States (POMS; McNair, Lorr, & Droppleman, 1992) shortened for diary studies. Analyzing two data sets, one composed of 35 daily reports from 68 persons experiencing a stressful examination and another composed of daily reports from 164 persons over a typical 28-day period, we demonstrate that three-item measures of anxious mood, depressed mood, anger, fatigue, and vigor have appropriate reliability to detect within-person change processes.     

Is categorization performance really intact in amnesia? A meta-analysis

Most published studies of category learning in amnesia have reported intact categorization performance. These results have been used to challenge single-system accounts of categorization and recognition, in which a single representational system mediates performance in these two tasks. Many of the published studies, however, have shown a numerical advantage for controls over amnesics and often have had low statistical power. A meta-analysis was conducted to assess whether this numerical advantage is significant when the data are pooled across studies. This analysis indicates that amnesic subjects do, in fact, show deficits in categorization tasks, which is consistent with single-system exemplar model predictions.     

Whose picture is this? Children's memory for item and source information

Children aged 3½ to 6½ years viewed pictures of common objects presented either once or three times on one of two consecutive days. A different hand puppet was used to present the pictures on each day, providing both perceptual and temporal cues to source. At test, old (studied) and new (non‐studied) pictures were presented for item recognition and source identification. Results showed that both item and source accuracy were higher for older (M = 5; 9 years) than younger children (M = 4; 6 years). Significant interactions between Age and Day of study were found for both item and source accuracy. For younger children, accuracy was higher for pictures studied on Day 1 than Day 2 (significant for source identification but not item recognition), whereas older children showed the opposite pattern: Higher accuracy for Day 2 than Day 1 (significant for item recognition but not source identification). Results are interpreted with respect to proactive interference and response bias. The utility of signal detection theory measures in determining the basis of age differences in performance of source identification is discussed.     

Can the MMPI-2 validity scales detect depression feigned by experts?

Major depression is one of the most frequently presented disorders for claims of psychiatric disability. Evidence also suggests that many individuals making claims of disability exaggerate or even fabricate mental illness. These facts suggest that the detection of feigned depression is an important task in psychiatric disability claim assessments. In this study, the capacity of a number of MMPI-2 validity scales and indicators to detect feigned depression was examined. Twenty-three mental health professionals with specific expertise and significant experience in assessing and treating major depression were asked to complete the MMPI-2 as if they were suffering from major depression. The MMPI-2 protocols of this sample were compared to those of a sample of patients diagnosed with major depression. Results indicated that the validity scales F, back F (FB), and the Dissimulation scale (Ds) were highly successful at distinguishing MMPI-2 protocols of feigned depression from bona fide depression. Replicating results from previous studies, however, FB proved most effective, outperforming all other validity scales and indicators, including F and Ds. These findings suggest that even experts are unable to feign major depression successfully on the MMPI-2, and that the FB scale might be the most effective indicator for detecting feigned depression.