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1.
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The potential impact of behavior analysis is limited by the public’s dim awareness of the field. The mass media rarely cover behavior analysis, other than to echo inaccurate negative stereotypes about control and punishment. The media instead play up appealing but less-evidence-based approaches to problems, a key example being the touting of dubious diets over behavioral approaches to losing excess weight. These sorts of claims distort or skirt scientific evidence, undercutting the fidelity of behavior analysis to scientific rigor. Strategies for better connecting behavior analysis with the public might include reframing the field’s techniques and principles in friendlier, more resonant form; pushing direct outcome comparisons between behavior analysis and its rivals in simple terms; and playing up the “warm and fuzzy” side of behavior analysis.  相似文献   

3.
Psychologists and neurobiologists have a long-standing interest in understanding how the context surrounding the events of our lives is represented and how it influences our behavior. The hippocampal formation emerged very early as a major contributor to how context is represented and functions. There is a large literature examining its contribution that on the surface reveals an array of conflicting outcomes and controversy. This review reveals that these conflicts can be resolved by building Nadel and Willner''s dual-process theory of context representations. Two general conclusions emerge: (1) There are two neural systems that can support context representations and functions—a neocortical system composed primarily of perirhinal and postrhinal cortices and a hippocampal system that includes perirhinal, postrhinal, entorhinal cortices, and the hippocampal formation. (2) These two systems are not equivalent—some context representations and functions are uniquely supported by the hippocampal system. These conclusions are discussed in the context of canonical ideas about the special properties of the hippocampal system that enable it to make unique contributions to memory.Everything we experience happens somewhere. The term “context” is often used to denote this “somewhere.” In the analysis of learning and memory, the context is like the setting for a stage play (Medin and Reynolds 1985). It provides the background for the real action in the drama—the main events. More importantly, as a consequence of learning and memory processes, the context often helps to select appropriate behaviors and determine the explicit and implicit content of our thoughts. Thus, it is not surprising that psychologists have a long-standing empirical and theoretical interest in understanding just what makes up a representation of context and how context representations interact with the main events of our lives to influence our behavior (see Balsam and Tomie 1985).More recently, neurobiologists have increased their interest in the problem of linking context representations and functions to brain systems. The hippocampal formation emerged quite early as a major focal point among many researchers. As a result, there is a substantial literature linking the hippocampal formation and context. However, on the surface, this research yields a dismaying set of conflicting results, with many findings that the hippocampal formation plays a critical role in supporting the influence of context on memory and behavior and many other findings that it does not.The goal of this article is to bring some clarity and order to this state of affairs. I start by providing a working definition of “context” that implicitly underpins its experimental analysis. I then describe several different functions of context that have been studied in the laboratory and are assumed to be theoretically important. I then introduce and build on a dual-process theory of context representations that was put forth several years ago by Lynn Nadel, Jeffrey Willner, and colleague (Nadel and Willner 1980; Nadel et al. 1985) and more recently by my colleagues and me (Rudy and O''Reilly 2001; Rudy et al. 2002). I then apply this framework to a wide range of outcomes from experiments that examined the role of the hippocampal formation in ways in which context influences memory and behavior. Two general conclusions emerge from this exercise. First is that two systems can support context representations and functions: (1) a neocortical system composed primarily of perirhinal and postrhinal cortices and (2) a hippocampal system that includes parahippocampal cortices; perirhinal, postrhinal, and entorhinal cortex; and the hippocampal formation. The second is that these two systems are not equivalent—some context representations and functions are uniquely supported by the hippocampal system. These conclusions are discussed in the context of long-standing ideas about the special properties associated with the hippocampal system that support its unique contributions to memory.  相似文献   

4.
In his seminal paper, “An Operational Analysis of Psychological Terms,” Skinner (1945) offered the revolutionary suggestion that, rather than endlessly debating the meanings of psychological terms, psychologists should analyze the variables that control their occurrence as verbal behavior. Skinner''s suggestion reflected the essence of his 1957 book, Verbal Behavior, wherein he argued that the behaviors of which language is composed (i.e., speaking and listening) are controlled by variables found in the social environment (which he called the verbal community), and that analyzing those variables would lead to an understanding of the behaviors. Although Skinner formally introduced his radical approach to language in 1945, it has yet to be fully realized. The result is that psychologists, including behavior analysts, still debate the definitions of terms. In the present paper, I review Skinner''s functional approach to language and describe ways in which behavior analysts have already applied it to traditional psychological terms. I conclude by looking at other current terms in behavior analysis that engender some confusion and encourage behavior analysts to apply a functional analytic approach to their own verbal behavior.  相似文献   

5.
Deterding et al. (Proceedings of the 15th International Academic MindTrek Conference: Envisioning Future Media Environments, USA 15: 9–15, 2011) report a recent rise in popularity of video game inspired software designed to address issues in a variety of areas, including health, energy conservation, education, and business. These applications have been based on the concept of gamification, which involves a process by which nongame activities are designed to be more like a game. We provide examples of how gamification has been used to increase health-related behavior, energy consumption, academic performance, and other socially-significant behavior. We argue that behavior analytic research and practice stands to benefit from incorporating successful elements of game design. Lastly, we provide suggestions for behavior analysts regarding applied and basic research related to gamification.  相似文献   

6.
Bloomfield''s “Linguistics as a Science” (1930/1970), Language (1933/1961), and “Language or Ideas?” (1936a/1970), and Skinner''s Verbal Behavior (1957) and Science and Human Behavior (1953) were analyzed in regard to their respective perspectives on science and scientific method, the verbal episode, meaning, and subject matter. Similarities between the two authors were found. In particular both asserted that (a) the study of language must be carried out through the methods of science; (b) the main function of language is to produce practical effects on the world through the mediation of a listener; and (c) a physicalist conception of meaning. Their differences concern the subject matter of their disciplines and their use of different models for the analysis of behavior. Bloomfield''s linguistics and Skinner''s functional analysis of verbal behavior are complementary approaches to language.  相似文献   

7.
Skinner’s radical behaviorism incorporates private events as biologically based phenomena that may play a functional role with respect to other (overt) behavioral phenomena. Skinner proposed four types of contingencies, here collectively termed the contingency horizon, which enable certain functional relations between private events and verbal behavior. The adequacy and necessity of this position has met renewed challenges from Rachlin’s teleological behaviorism and Baum’s molar behaviorism, both of which argue that all “mental” phenomena and terminology may be explained by overt behavior and environment–behavior contingencies extended in time. A number of lines of evidence are presented in making a case for the functional characteristics of private events, including published research from behavior analysis and general experimental psychology, as well as verbal behavior from a participant in the debate. An integrated perspective is offered that involves a multiscaled analysis of interacting public behaviors and private events.  相似文献   

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Research indicates that perceivers regulate information gain from their observation of ongoing behavior by varying the number and kind of actions they identify as meaningful. Although numerous factors have been shown to induce variation in this behavior-perception process, it is not currently known whether observers must consciously and intentionally initiate these changes. To address this question, different observational goals (impression formation or memorization) were nonconsciously primed in participants who then viewed and segmented a behavior sequence into meaningful actions. Although participants were unaware of its effects, the priming manipulation led to quantitative and qualitative shifts in their perception of the behavior that were similar to those found in a previous study in which observational goals were manipulated via explicit instructions. Importantly, these shifts in perception, in turn, influenced evaluations of the observed actor and memory for her behavior. We conclude that an act of will is not required for adjustments in behavior perception to be initiated, and, furthermore, that a full understanding of social judgment cannot be achieved without examination of the behavior-perception process.
G. Daniel LassiterEmail:
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10.
A detailed analysis is presented of the ways in which control by the negative stimulus in two-comparison conditional discriminations may be expected to affect the outcome of tests for the properties of equivalence relations. Control by the negative stimulus should produce the following results: (a) no observable effect on symmetry tests; (b) reflexivity test results should look like “oddity” rather than “identity”; and (c) transitivity tests that involve an odd number of nodes should yield results that are 100% opposite to tests that involve an even number of nodes. The analysis also considers the effects of variation in the type of comparison-stimulus control between and within baseline conditional discriminations. Methods are suggested for experimentally regulating the type of control, and for verifying the predictions that the analysis generates. If suggested experiments continue to support the analysis, investigators who use two-comparison conditional discriminations to study equivalence relations will either have to control explicitly whether the positive or the negative comparison governs their subjects' choices, or they will have to abandon two comparisons and use three or more comparisons instead.  相似文献   

11.
Stimulus properties of conspecific behavior   总被引:4,自引:2,他引:2       下载免费PDF全文
Two experiments identified the conditions in which the behavior of one bird acquired discriminative control of the behavior of a second bird. The schedule-controlled behaviors of the “stimulus” bird were differentially correlated with the components of a multiple schedule according to which the pecking of an “experimental” bird produced food. In Experiment 1, three pairs of pigeons acquired a successive discrimination and two reversals with the conspecific stimuli. Experiment 2 included a control condition in which no systematic relationship existed between the conspecific stimuli and the component schedules. While differential responding during the components of the multiple schedule was again found when the conspecific stimuli were available, differential responding did not occur in the control condition. Test conditions included in the experiments indicated that (a) the differential responding was not dependent on the discriminative properties of reinforcement, (b) the pecking of the stimulus and experimental birds was temporally interrelated, (c) the visual conspecific stimuli were critical to the maintenance of the discrimination, and (d) the observed stimulus control immediately generalized to an unfamiliar conspecific.  相似文献   

12.
Three standardized measures of child and adolescent behavior are reviewed for their attention to issues salient in the experiences of girls in late childhood and adolescence (ages 12 to 18; American; American and Brown & Gilligan 1992). The Achenbach Child Behavior Checklist and Teacher Report Form (Achenbach and Achenbach), the Behavior Assessment System for Children (Reynolds & Kamphaus, 1992), and the Social Skills Rating System (Gresham & Elliott, 1990) are analyzed. Challenges to psychologists in schools for including the experiences of girls in the knowledge base grounding their practice and research are articulated.  相似文献   

13.
Behavior analysis has produced a robust theoretical analysis of the contingencies involved in cultural evolution. Yet, thus far, the empirical yield of this work remains quite limited. With this paper, I attempt to provide specific examples of the ways to advance an experimental analysis of the contingencies involved in cultural evolution. I begin with a review of the theoretical analyses developed by behavior analysts and other contextually oriented scientists. Next, I submit that, if the goal of our science is both predicting and influencing cultural phenomena, we must produce experimental analyses of the impact of meta-contingencies on organizations’ practices. There is no more pressing reason for doing this than the threat of climate change posed by the continuing growth in human use of fossil fuels. Therefore, the paper provides an analysis of the contingencies influencing organizational practices now affecting continued use of fossil fuels and the contingencies for organizations seeking to prevent their use. One concrete step to advance a science of cultural change relevant to climate change would be to create a database of organizations that are promoting vs. working to prevent fossil fuel consumption and the consequences that seem to maintain their practices. I call for experimental analysis of the impact of altering consequences for these practices and for experimental analyses of interventions intended to change the norms, values, and behavior of organizational leaders who can influence fossil fuel consumption. I then discuss the role of prosocial behavior and values in affecting behavior relevant to reducing fossil fuel consumption because the empirical evidence shows that prosociality favors more “green” behavior. Recent advances in prevention research have identified interventions to promote prosociality, but we need experimental analyses of how advocacy organizations can be more effective in getting these interventions widely adopted.  相似文献   

14.

Aim

The purpose of the study is to assess the influence of prone or supine position on sleep states and on withdrawal and approach reactions of preterm infants.

Methods

Thirty-two preterm infants from Meir Medical Center, Israel, mean post menstrual age 30.37 ± 2.57, mean birth weight 1250 g ± 313.86, participated in the study. Infants were studied during 48 h. Positions (prone and supine) were alternated every 3-4 h after feedings. Sleep states were assessed by Actigraph measurement and by two daily 30-min Naturalistic Observations of Newborn Behavior (NONB) to confirm sleep states and for recording the behavioral reactions (approach and withdrawal).

Results

In the prone position there were more approach reactions as compared to withdrawal reactions (p < .001) while in the supine position, the approach and withdrawal reactions were comparable. In the prone position more sleep patterns (deep sleep, light sleep, drowsy) were observed as opposed to more awake patterns (quiet awake, active awake and agitated fussy) that were seen in the supine position.

Conclusions

Clinical implications encourage placing the preterm infant in the prone position while in the NICU. This enables important achievements such as longer periods of quality sleep, and production of adaptive self-regulatory reactions.  相似文献   

15.
Malone (The Behavior Analyst, 37, 1–12 2014) argued that the emergence of behaviorism was inevitable with or without Watson’s participation, mainly because protobehavioral ideas and dissatisfaction with classical structuralism were already widespread. However, the first premise is questionable because many of the ideas Malone cited were consistent with structuralism rather than behaviorism, and even if both premises were true they would not make the emergence of behaviorism—or anything else—inevitable. Historical evidence for inevitability is always retrospective and therefore always allows the logical fallacy of “after this, therefore because of this.” In the relevant real world Watson existed, he was a psychologist, he was the first to publish an article that described a “behaviorism,” and he promoted his behaviorism in later works. Stories about what would have happened without Watson’s participation are therefore counterfactual and this lack of historicity makes the stories fictional rather than scientific. In the real world, Watson founded behaviorism.  相似文献   

16.
Two experiments examined apparent signal probability effects in simple verbal self-reports. After each trial of a delayed matching-to-sample task, young adults pressed either a “yes” or a “no” button to answer a computer-presented query about whether the most recent choice met a point contingency requiring both speed and accuracy. A successful matching-to-sample choice served as the “signal” in a signal-detection analysis of self-reports. Difficulty of matching to sample, and thus signal probability, was manipulated via the number of nonmatching sample and comparison stimuli. In Experiment 1, subjects exhibited a bias (log b) for reporting matching-to-sample success when success was frequent, and no bias or a bias for reporting failure when success was infrequent. Contingencies involving equal conditional probabilities of point consequences for “I succeeded” and “I failed” reports had no systematic effect on this pattern. Experiment 2 found signal probability effects to be evident regardless of whether referent-response difficulty was manipulated in different conditions or within sessions. These findings indicate that apparent signal probability effects in self-report bias that were observed in previous studies probably were not an artifact of contingencies intended to improve self-report accuracy or of the means of manipulating signal probability. The findings support an analogy between simple self-reports and psychophysical judgments and bolster the conclusion of Critchfield (1993) that signal probability effects can influence simple self-reports much as they do reports about external stimuli in psychophysical experiments.  相似文献   

17.
Four rhesus monkeys learned both a color and tilt discrimination. The stimuli were combined to produce incompatible behavior. The behavior controlled by one set of stimuli was reinforced until “errors” virtually disappeared. The stimuli were tested separately again. Sixteen replications of the entire procedure indicated that the stimuli producing “errors” were ignored.  相似文献   

18.
Subjects who were told they were “experimenters” attempted to reinforce fluent speech in a supposed subject with whom they spoke via intercom. The supposed subject was to say nouns, one at a time, on request by the “experimenter”, who reinforced fluent pronunciation with points. Actually, the “experimenter” was talking to a multi-track tape recording, one track of which contained fluently spoken nouns, the other track containing disfluently spoken nouns. If the “experimenter's” request for the next noun was in a specified form a word from the fluent track was played to him as reinforcement; requests in any other form produced the word from the disfluent track. Repeated conditioning of specific forms of requests was accomplished with two subject-“experimenters,” who were unable to describe changes in their own behavior, or the contingencies applied. This technique improved upon an earlier method that had yielded similar results, but was less thoroughly controlled against possible human bias.  相似文献   

19.
Rodent studies have suggested that “pattern separation,” the ability to distinguish among similar experiences, is diminished in a subset of aged rats. We extended these findings to the human using a task designed to assess spatial pattern separation behavior (determining at time of test whether pairs of pictures shown during the study were in the same spatial locations). Using a standardized test of word recall to divide healthy aged adults into impaired and unimpaired groups relative to young performance, we demonstrate that aged impaired adults are biased away from pattern separation and toward pattern completion, consistent with the rodent studies.Memory impairment is a common complaint among aging individuals, yet the variability within the aging population is great in both rats (Gallagher et al. 2006; Robitsek et al. 2008) and humans (Hilborn et al. 2009). A rodent model of aging (Gallagher et al. 2006; Wilson et al. 2006) has demonstrated that ∼50% of healthy rats qualify as cognitively “impaired” by scoring outside the range of the young performance in a standard protocol (Gallagher et al. 1993). The other half, the “unimpaired” rats, perform on par with young adults, demonstrating a natural degree of variability in cognitive aging. In this study, we sought to capitalize on the variability observed in the aging of both rats and humans in a study of spatial pattern separation.One source of variability in memory performance is hypothesized to be tied to changes in the input to the dentate gyrus (DG), which has been shown in the rat to be affected by the aging process. Smith et al. (2000) reported a selective impairment in layer II entorhinal input into the DG and CA3 regions of the hippocampus in rats with cognitive impairment. Similarly, the number of synapses in the outer receiving layer of DG was reduced in autopsied aged brains and correlated with earlier performance on a delayed recall task (Scheff et al. 2006). Finally, in a human imaging study, Small et al. (2002) observed that 60% of their aging sample demonstrated diminished MRI signal in the hippocampal region (including the DG) and also had a greater decline in memory performance. These findings support the notion that changes in the DG associated with aging may affect memory performance.The DG may be particularly important for the computations that underlie pattern separation (Treves and Rolls 1994; McClelland et al. 1995; Norman and O''Reilly 2003). “Pattern separation” refers to the process by which similar inputs are stored as distinct, nonoverlapping representations. In contrast, “pattern completion” refers to the process by which an existing representation can be reinstated by the presentation of a partial or degraded cue. Numerous studies in the rodent have identified the importance of the DG for pattern separation using electrophysiological methods (Leutgeb et al. 2004, 2005, 2007; Leutgeb and Leutgeb 2007), immediate early gene expression (Vazdarjanova and Guzowski 2004), lesions (Lee et al. 2005; Gilbert and Kesner 2006; Goodrich-Hunsaker et al. 2008), and even genetic manipulations (Cravens et al. 2006; Kubik et al. 2007; McHugh et al. 2008). Human neuroimaging has also recently identified activity in the DG (and CA3 regions of the hippocampus) in an object pattern separation task (Kirwan and Stark 2007; Bakker et al. 2008).Given the importance of the DG in pattern separation and its vulnerability to changes that occur with aging, studies have begun to examine pattern separation in older adults. Our laboratory has designed a task to examine object-based pattern separation performance in humans (Kirwan and Stark 2007). In this task, pictures of objects were presented either once or repeatedly throughout the task. Critically, some of the items presented were lures that were similar but not identical to previously shown items. The overlapping features of the lures more heavily engaged pattern separation processes. In young adults, functional magnetic resonance imaging (fMRI) activity in the DG was sensitive to the lures, indicating a role in pattern separation processes in both an explicit (Kirwan and Stark 2007) and implicit (Bakker et al. 2008) version of this task. Toner et al. (2009) used the explicit version of this task to demonstrate that older adults showed a greater tendency to identify lures as “old” (repeated) relative to young adults. These findings were also recently replicated in our laboratory (Yassa et al., in press), with the additional demonstration that older adults exhibit greater fMRI CA3/DG activity for the lures during both encoding and retrieval.Since object-based pattern separation appears to be modulated by the DG in humans, we wondered if these findings could be extended to spatial pattern separation. Rodent studies have demonstrated that the DG has a particular role in spatial pattern separation (Gilbert et al. 2001; Kesner et al. 2004). Specifically, Hunsaker et al. (2008) placed rats with localized DG lesions in an environment with two objects spaced 60 cm apart. When the animals were later placed in the same environment with the same objects now placed 40 cm apart, DG-lesioned animals (unlike control animals) did not re-explore the objects or environment. These data suggest that the DG-lesioned rats were not able to discriminate between the training and test environments. That is, they were impaired in spatial pattern separation. Since converging evidence suggests that one feature of the aging process can be characterized as a DG knockdown, we modified this task design for humans to test spatial pattern separation performance in older adults. While the Hunsaker et al. (2008) task emphasized the distance between the two objects as the source of interference creating a greater need for pattern separation, the paradigm presented here moves an object in any direction, changing both the distance and the angle (i.e., changing more of the spatial relations). We posit that this amount of movement (close, medium, or far) may place similar demands on spatial pattern separation processes as in the rodent task.The present study included 20 young adults (mean age 19.9 yr, range 18–27 yr) and 30 aged adults (mean age 70.4 yr, range 59–80 yr). Aged adults completed a battery of standardized neuropsychological tests, including the Mini-Mental State Exam (Folstein et al. 1975), Rey Auditory–Verbal Learning Task (RAVLT) (Rey 1941), Digit Span, Vocabulary, and Matrices subtests from the Wechsler Adult Intelligence Scale III (Wechsler 1997). The Vocabulary and Matrices scores were entered into a weighted formula along with age, gender, and education to derive estimated IQ scores (Schoenberg et al. 2003). All aged participants scored within the normal age-adjusted ranges on these measures and were cognitively intact. Younger adults also completed the RAVLT and scored within the normal age-adjusted range. These data are presented in Table 
YoungAged (AU)Aged (AI)
UnimpairedImpaired
Years of age19.9 (2.4)69.1 (5.2)72.9 (4.1)
Years of education14.1 (1.7)a16.7 (1.8)15.5 (2.9)
Gender (male/female)3M/17F6M/14F5M/5F
RAVLT total performance53.5 (6.7)56.2 (6.4)43.4 (6.1)b
RAVLT immediate performance12.1 (1.9)12.2 (1.5)8.3 (1.9)b
RAVLT delay performance11.8 (1.4)11.8 (1.6)6.5 (1.7)b
Estimated IQ120.8 (5.5)115 (6.7)b
Digit span performance18.9 (4.5)17 (3.8)
Mini-Mental State examination28.6 (0.9)28.3 (0.9)
Open in a separate windowAll data are reported as mean (SD).aAn unpaired t-test revealed higher years of education for the aged adults (16.3, SD 2.3) than the young adults (14.1, SD 1.7), t(48) = 3.7, P < 0.001.bIn addition, unpaired t-tests showed a poorer performance for the AI group relative to the AU group for RAVLT Total t(28) = 5.2, P < 0.0001, RAVLT Immediate t(28) = 6.3, P < 0.0001, and RAVLT Delay t(28) = 8.6, P < 0.0001. Although there is a group difference in IQ t(26) = 2.5, P < 0.05, these are largely overlapping distributions, and the AI group''s IQ scores are certainly within normal limits. In addition, there was no relationship between IQ scores and performance on any of the tasks or other measures we used.The Spatial Pair Distance (SPD) task consisted of 10 study and test blocks for a total of 100 test pairs. Participants studied 10 unique pairs of pictures per block and were then tested on whether each of the 10 pairs was in the same or different locations compared to the study session. During the study session, participants viewed pairs of pictures for 2 sec each and were told to “try to remember the location of the pictures.” During the test session, participants were told to indicate (with a key press) whether the pictures were in the same location as before or whether one of the pictures was in a different location. They were not told which of the two pictures might change position and the test was self-paced. Critically, for the different trials, only one picture of the pair changed location. It could be moved a small amount (close; 10%–20% of the screen; 2.64°–5.72° of visual angle), a moderate amount (medium; 25%–35% of the screen; 6.64°–9.38° of visual angle), or a large amount (far; 40%–60% of the screen; 10.62°–15.94° of visual angle) as shown in Figure 1. We limited the placement of the pictures between 10% and 90% of the screen so that the images were never placed along the edge of the computer screen. For the different condition, one of the images was moved in the x-coordinate by a percentage of the screen (i.e., 10%–20% in the close condition) and in the y-coordinate by a percentage of the screen (i.e., 10%–20% in the close condition), while the other image remained in its original location.Open in a separate windowFigure 1.SAME and DIFFERENT (separated into close, medium, and far amounts of movement) conditions for the Spatial Paired Distance task. The dashed-line box demonstrates the original location of the second picture, but was not shown to the participants.The probability to respond “different” for the SAME and three DIFFERENT (close, medium, and far) conditions for young and aged adults is shown in Figure 2A. A 2 × 4 analysis of variance (ANOVA) with group (young and aged adults) as a between-group factor and condition (same, close, medium, far) as a within-group factor revealed a main effect of condition, F(3,192) = 35.62, P < 0.0001. A post-hoc trend analysis revealed a positive linear trend across the four conditions, r2 = 0.62, P < 0.0001. There was no effect of group or an interaction, indicating no overall difference in spatial pattern separation ability between young and aged adults.Open in a separate windowFigure 2.(A) The mean proportion correct for each of the four conditions. There is a main effect of Condition, with a linear trend of increasing DIFFERENT responses across the conditions, but no difference between the younger adults and aged adults. (B) When the aged adults are separated according to their RAVLT Delay performance into impaired (AI) and unimpaired (AU), the AI adults perform significantly worse than both the young and the AU adults on the three DIFFERENT conditions. (C) Averaging the groups'' performance on the DIFFERENT trials emphasizes the finding that AI performance is matched on the SAME condition and is selectively impaired on the DIFFERENT conditions that tax spatial pattern separation.Since we were interested in the variability associated with healthy aging, we explored the aged group further. While rats are typically divided into impaired and unimpaired groups based on their performance in the Morris water maze (Gallagher et al. 1993), we divided the aged group into aged unimpaired (AU) and aged impaired (AI) based on their RAVLT delayed word learning performance. Importantly, the aged impaired individuals scored within the normal range for their own age group (ages 60–80). Aged unimpaired participants scored within the normal range for young individuals (ages 20–29) on the delayed test of the RAVLT (mean words recalled 11.8, range 9–15), whereas aged impaired individuals scored more than 1 standard deviation below these norms (mean words recalled 6.5, range 5–8). Thus, the aged impaired group was not clinically impaired and only mildly impaired relative to the young. While the aged unimpaired (69.1 yr, range 59–78) group is marginally different from the aged impaired (72.9 yr, range 67–80) group, t(28) = 2.02, P = 0.053, there was not a significant correlation (r2 = 0.06, ns) between performance on the DIFFERENT conditions and age as might be expected if age alone were responsible for the pattern separation impairments reported here. These data are presented in Figure 2B.We entered the aged unimpaired and impaired groups into a 3 × 4 ANOVA with Group (Young, AI, and AU) and Condition as factors. We found a main effect of Condition as before, F(3,188) = 29.1, P < 0.0001. Critically, we also found an effect of Group, F(2,188) = 4.7, P < 0.05, such that the aged impaired group performed worse on the DIFFERENT conditions. We then calculated a separation bias score by averaging the three DIFFERENT conditions together (Fig. 2C) and analyzed these scores with a 2 × 2 ANOVA with Group and Condition as factors. Again, there was a main effect of Group F(2,94) = 4.7, P < 0.05; a main effect of Condition, F(1,94) = 500.8, P < 0.0001; and an interaction, F(2,94) = 4.7, P < 0.05. Bonferroni-corrected post-tests identified that the AI group was significantly impaired on the DIFFERENT trials compared to the AU group, t(94) = 4.1, P < 0.001; and the Young group, t(94) = 1.9, P < 0.05. These analyses all emphasize the same finding, namely, that AI individuals are impaired on the conditions taxing spatial pattern separation (i.e., DIFFERENT), but are not impaired on the condition that does not tax separation per se (i.e., SAME).Using the RAVLT delayed recall performance to divide the aged group into AI and AU was an effective way to capture some of the individual variability in memory performance exhibited in the aged group. Indeed, there was a strong correlation between the aged impaired RAVLT scores and their performance on the DIFFERENT trials. We entered the RAVLT delayed recall scores into a linear regression with their performance on the average of the DIFFERENT trials and found a positive linear correlation such that as RAVLT delayed recall scores increased, performance on the different trials increased, r2 = 0.28, P < 0.01 (Fig. 3A). When the AI and AU groups were split, we observed that the AI group''s correlation remained reliable, r2 = 0.40, P < 0.05, while the AU group no longer exhibited a significant correlation, r2 = 0.03, ns. These data support the notion that spatial pattern separation performance may be a sensitive index of memory variability in aging.Open in a separate windowFigure 3.For the aged group, there is a positive relationship between SPD different trial performance and RAVLT delay performance (A), SPD different trial performance and MS separation score performance (B), and MS separation score performance and RAVLT delay performance (C). These positive relationships indicate some shared underlying process that may be captured by individual differences in memory performance during the course of aging.Since we collected additional behavioral measures on the same sample, we sought to determine if spatial pattern separation performance and RAVLT delayed recall performance might predict object pattern separation performance. Twenty-eight of the aged adults also participated in the object pattern separation paradigm as detailed by Yassa et al. (in press). Briefly, participants encoded everyday objects by simply making an indoor/outdoor judgment. During the test session, they viewed the same object (REPEATS), similar objects (LURES), and new objects (FOILS). They were required to make an “old,” “similar,” or “new” judgment for each item. We then computed a separation bias score by subtracting the probability of making “similar” responses to the FOILS from the probability of making “similar” responses to LURES, that is, p(“similar”) | LURE − p(“similar”) | FOIL. As reported by Yassa et al. (in press) the separation bias in the aging group was reduced relative to young adults, consistent with the Toner et al. (2009) findings.If spatial pattern separation as assessed by the SPD task is engaging an underlying process similar to that engaged in object pattern separation, we would predict a positive relationship between SPD and object mnemonic similarity (OMS) task performance. We computed average performance on the DIFFERENT conditions (close, medium, and far) and entered it into a linear regression with the OMS separation score for each individual in the aged group. We observed a positive relationship, r2 = 0.26, P < 0.01, as shown in Figure 3B. Likewise, we hypothesized a positive relationship between the OMS separation score and RAVLT delay performance, since we observed such a relationship with SPD performance. We entered these data into a linear regression and again observed a positive relationship, r2 = 0.22, P < 0.05 (with one OMS outlier greater than two SDs removed), as shown in Figure 3C. We also examined the relationship between SPD performance and Digit Span performance and estimated IQ in the aged group, but we did not find any significant correlations. These data indicate that these measures of both object and spatial pattern separation are behavioral manifestations of a similar underlying process that may also be somewhat accounted for by RAVLT delay recall performance.One pertinent question is whether RAVLT performance would predict SPD performance in the Young group, making it a sensitive measure regardless of aging per se. When we examined this question by entering SPD performance on the average of the DIFFERENT conditions and RAVLT delay performance into a linear regression (two SPD outliers greater than two SDs removed), we found no evidence for this hypothesis (r2 = 0.02, ns). Likewise, it might appear circular to define the AI group based on their poorer RAVLT memory performance and then identify poorer performance on the SPD task. However, the AI versus AU difference is selective for the DIFFERENT condition, yet performance is matched for the SAME condition. One would expect both the SAME and DIFFERENT conditions to be similarly adversely affected if a general memory impairment could account for the poorer AI performance.We suggest that these data support the notion of an impairment in spatial pattern separation processing in AI individuals. Ideally, we would have predicted a gradient of this effect, with more severe impairments in performance in the Close condition and matched performance in the Far condition. Unfortunately, the performance in the Close condition is near the floor, with all groups hovering around chance performance (50%). This potential floor effect may be obscuring a greater deficit in the Close condition for the AI group. On the other end, performance on the Far condition may be suffering a bit from a ceiling effect. Performance in the Far condition is not much better than the same condition in any group, and that same performance is only ∼74% for each group. Therefore, the difficulty associated with this task may be such that we cannot create an “easy” enough Far condition to increase the percentage correct. Indeed, pilot testing on manipulations of this task (moving both items at test instead of just one, for example) did not result in greater accuracy performance for older or younger adults. While these data are not able to speak to a gradient of spatial pattern separation, we would argue that the selective impairments for the AI group for the DIFFERENT condition still reflect a deficit in spatial pattern separation processes.The Spatial Paired Distance task presented here appears to be a measure that is sensitive to individual variations in memory performance associated with aging. The dentate gyrus seems a likely candidate for the source of this variability given its involvement in rodent (Small et al. 2004) and human aging studies (Small et al. 2002). Future research quantifying the structural and functional integrity of the dentate gyrus and other medial temporal lobe structures may elucidate those relationships with this task. Whether the variability associated with this task is a source of natural variation in the aged population or a precursor to mild cognitive impairment and possibly Alzheimer disease (AD) is also not clear. Longitudinal assessment of these or other individuals would be required to determine whether those in the AI group were more likely to develop AD. If such is the case, then the SPD and object mnemonic similarity tasks may be particularly useful for early detection and diagnosis of pathological changes associated with dementia. Similarly, these tasks may be advantageous for use as outcome measures in clinical trials of new medications aimed at addressing these changes.  相似文献   

20.
When History Seems to Repeat Itself: Exposure to Perceived Lessons of the Past Influences Predictions About Current Political Events     
Djouaria Ghilani  Olivier Luminet  Olivier Klein 《Psychologica Belgica》2022,62(1):89
The idea that the past holds lessons for the present, under the guise of historical analogies, is prevalent in political and public discourse. Those analogies are often accompanied by dire warnings befalling those who “forget” or otherwise neglect the powerful lessons of History—and would then be “doomed to repeat it”, as the saying goes. So, Would remembering history make it seem more OR LESS likely to repeat itself in the future? In other words, does exposure to specific lessons about past events, especially ones involving causal claims, affect how people expect real-life events to turn out? Four studies (three preregistered) tested this experimentally. In Studies 1 and 2, participants expected the same behavior (the US adopting a harsh stance against Iran in the Nuclear Treaty) to result in a more negative outcome when this current stance seemed to match a “lesson” they had read about the break-out of World War II (European leaders adopting a harsh approach against Germany in the 1919 Versailles Treaty vs. a conciliatory approach in the 1938 Munich Agreement). Studies 3 and 4 attempted to eliminate some confounds present in the first two studies and to generalize the effect to different events. While results varied across studies, an internal meta-analysis indicated that the analogical effect on predictions (d = –.08) tended to become stronger as participants’ knowledge about the target situation decreased (d-1SD = –.24). These findings support the possibility of analogical-based predictive effects for real-life political events, and are discussed in light of their research and political implications.  相似文献   

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