Now you see it; now you don't: inhibiting recall and recognition of scenes

Postevent misleading information can distort people's memories by altering and adding scenes. But can you also inhibit the retrieval of information from memory? In two studies we show that postevent information can make memory for a scene less accessible. In both studies participants first saw an event (e.g. a restaurant scene displayed in slides, or a drunk‐driving incident shown via a video clip). Later they were shown the same event without a critical scene and were told either to use this to generate a story (Experiment 1) or to imagine the event (Experiment 2). Finally they were tested. Relative to controls, this postevent omission led to fewer people reporting the critical scene in free recall and in recognition. Thus, we demonstrated that it may be possible to inhibit memories. This finding has important implications for eyewitness testimony and the recovered memory debate. Copyright © 2001 John Wiley & Sons, Ltd.     

On Basic Logical Knowledge; Reflections on Paul Boghossian's "How Are Objective Epistemic Reasons Possible?'

Philosophical Studies -     

On the heritability of inspection time and its covariance with IQ: a twin study

Using the classical twin design, this study investigates the influence of genetic factors on the large phenotypic variance in inspection time (IT), and whether the well established IT–IQ association can be explained by a common genetic factor. Three hundred ninety pairs of twins (184 monozygotic, MZ; 206 dizygotic, DZ) with a mean age of 16 years participated, and 49 pairs returned approximately 3 months later for retesting. As in many IT studies, the pi figure stimulus was used and IT was estimated from the cumulative normal ogive. IT ranged from 39.4 to 774.1 ms (159±110.1 ms) with faster ITs (by an average of 26.9 ms) found in the retest session from which a reliability of .69 was estimated. Full-scale IQ (FIQ) was assessed by the Multidimensional Aptitude Battery (MAB) and ranged from 79 to 145 (111±13). The phenotypic association between IT and FIQ was confirmed (−.35) and bivariate results showed that a common genetic factor accounted for 36% of the variance in IT and 32% of the variance in FIQ. The maximum likelihood estimate of the genetic correlation was −.63. When performance and verbal IQ (PIQ & VIQ) were analysed with IT, a stronger phenotypic and genetic relationship was found between PIQ and IT than with VIQ. A large part of the IT variance (64%) was accounted for by a unique environmental factor. Further genetic factors were needed to explain the remaining variance in IQ with a small component of unique environmental variance present. The separability of a shared genetic factor influencing IT and IQ from the total genetic variance in IQ suggests that IT affects a specific subcomponent of intelligence rather than a generalised efficiency.     

Evidence of Impaired Glucose Tolerance and Insulin Resistance in Patients With Alzheimer’s Disease

Alzheimer’s disease (AD) and diabetes rarely occur together, a finding that provides a possible clue as to the development of AD. Abnormal glucose metabolism is not limited to diabetes, but also can include impaired glucose tolerance, insulin resistance, and hyperinsulinemia. AD patients have significantly varying insulin levels after drinking sugared sodas and thus may be classified as insulin resistant. After reviewing the literature on impaired glucose tolerance and insulin production in AD, we present several hypotheses as possible explanations for the relationship between insulin resistance and AD. Finally, we suggest future studies, including studies on use of thiazolidinediones (currently used in the treatment of diabetes) in AD.     

Contextual Interference: A Response Planning Account

In two of the three experiments that are reported subjects were trained in either a blocked or a random practice schedule and allowed to self-select the amount of time they used to plan an upcoming movement. According to the reconstruction hypothesis (Lee & Magill, 1985) random practice participants engage greater movement planning processes (i.e. action plan re-construction) during acquisition than do their blocked practice counterparts. It was predicted that such reconstructive activity would be manifest as greater study time being used by random practice subjects as they readied themselves for an imminent response. Data from Experiments 1 and 2 supported this study time prediction while also revealing the typical retention benefit associated with random practice. Interestingly, the acquisition benefit often apparent with blocked practice was not evident when the random practice participants were given sufficient time to plan the upcoming response. These conclusions were supported by data from Experiment 3 that involved a direct manipulation of the amount of study time afforded random and blocked practice participants. Taken together, these data are consistent with the suggestion from the reconstruction hypothesis that more time is necessary for intratrial planning processes during random practice formats. Furthermore, acquisition differences that are commonly observed between high and low contextual interference practice conditions may, at least in part, be associated with the completion of the extra planning processes entertained by random practice participants as the movement is being executed.     

On the misuse of group membership

Group membership is analyzed from the perspective of developmental theory. Maladaptive or nontransitional uses of the groups of everyday life, such as work and social groups as well as therapy groups, are discussed and illustrated with clinical examples. It is recommended that therapists pay attention to the nature and meaning of their patients' involvements in these sorts of groups, keeping in mind that the meanings of such affiliations are particularly influenced by developmental factors.     

The Development of the Attitudes Toward Censorship Questionnaire1

Two studies were conducted to develop a psychometrically sound scale to measure attitudes to ward censorship. In the first study, 37 initial items were administered to 109 college and high school students. Additional measures were also included for validation purposes. Factor analysis and item-total correlations were used to select items for the final scale. Results revealed two distinct factors alluding to the possibility of a multidimensional construct. Reliability coefficients indicated that both factors were internally consistent. Correlations with additional measures provided evidence for the criterion and convergent validity of the scale. The second study used a sample of 150 college students to replicate the initial findings and to establish testretest reliability.     

Mobilizing positive reinforcement in communities to reduce youth access to tobacco

A community intervention to mobilize positive reinforcement for not selling tobacco to young people was evaluated. The intervention had five components: (a) mobilization of community support, (b) merchant education, (c) changing consequences to clerks for selling or not selling to those under 18, (d) publicity about clerks’ refusals to sell, and (e) feedback to store owners or managers about the extent of their sales to adolescents. A multiple baseline design experiment was conducted, in which two small Oregon communities received the intervention, while two others continued in baseline. Outlets’ willingness to sell was assessed repeatedly by teenage volunteers. The intervention significantly reduced the proportion of stores willing to sell. Mobilizing socia and material reinforcement for stores not selling tobacco to young people is a viable means of reducing such sales. It may be especially valuable in communities where laws against sales to minors go unenforced. This paper supported in part by the National Cancer Institute Grant CA38273.     

The conjunction fallacy: A test of averaging hypotheses

The conjunction fallacy, in which individuals report that the conjunction of two events is more rather than less likely to occur than one of the events alone, is a robust phenomenon. We assessed the possibility that an analysis in terms of functional measurement methodology might be consistent with occurrence of the fallacy. A 3 × 3 design in which we varied the judged likelihood of the two components constituting the conjunction permitted us to assess the possibility that subjects judge the likelihood of conjunctions by averaging the likelihood of their component parts. The results were consistent with this possibility, and this interpretation was supported by analysis of the results in terms of functional measurement methodology.     

Multicultural Training in University Counseling Center Predoctoral Psychology Internship Programs: A Survey

Research indicates that graduate programs in counseling and clinical psychology are beginning to include more courses on multicultural issues. Little data is available, however, concerning the inclusion of training in multicultural issues in predoctoral psychology internship training programs. This study examined the amount and type of such training actually occurring at predoctoral psychology internship training programs in university counseling centers.