Memory for spatial location: Cue effects as a function of field rotation

We developed theoretical extensions of Huttenlocher, Hedges, and Duncan's (1991) category-adjustment model of human spatial memory to incorporate the use of fuzzy boundariesand cue-determined prototypes. In two experiments, people reproduced locations of dots in a circle, while the number of external reference cues varied. In Experiment 1, the task field was stable and results were consistent with the use of fixed categories unaffected by number of cues. In Experiment 2, the task field was made dynamic by rotation on most trials, with results evaluated for nonrotation trials. The large cue effects observed for angular bias were consistent with the proposed cue-based fuzzy-boundary model. Large cue effects were also observed for absolute error, consistent with a model in which proximity to cues predicts stability of memory. Results point to the key role of orientation to the task environment in determining whether categorical encoding is based on cues.     

Overcoming default categorical bias in spatial memory

In the present study, we investigated whether a strong default categorical bias can be overcome in spatial memory by using alternative membership information. In three experiments, we tested location memory in a circular space while providing participants with an alternative categorization. We found that visual presentation of the boundaries of the alternative categories (Experiment 1) did not induce the use of the alternative categories in estimation. In contrast, visual cuing of the alternative category membership of a target (Experiment 2) and unique target feature information associated with each alternative category (Experiment 3) successfully led to the use of the alternative categories in estimation. Taken together, the results indicate that default categorical bias in spatial memory can be overcome when appropriate cues are provided. We discuss how these findings expand the category adjustment model (Huttenlocher, Hedges, & Duncan, 1991) in spatial memory by proposing a retrieval-based category adjustment (RCA) model.     

The role of experience in location estimation: Target distributions shift location memory biases

Research based on the Category Adjustment model concluded that the spatial distribution of target locations does not influence location estimation responses [Huttenlocher, J., Hedges, L., Corrigan, B., & Crawford, L. E. (2004). Spatial categories and the estimation of location. Cognition, 93, 75–97]. This conflicts with earlier results showing that location estimation is biased relative to the spatial distribution of targets [Spencer, J. P., & Hund, A. M. (2002). Prototypes and particulars: Geometric and experience-dependent spatial categories. Journal of Experimental Psychology: General, 131, 16–37]. Here, we resolve this controversy by using a task based on Huttenlocher et al. (Experiment 4) with minor modifications to enhance our ability to detect experience-dependent effects. Results after the first block of trials replicate the pattern reported in Huttenlocher et al. After additional experience, however, participants showed biases that significantly shifted according to the target distributions. These results are consistent with the Dynamic Field Theory, an alternative theory of spatial cognition that integrates long-term memory traces across trials relative to the perceived structure of the task space.     

Two-category place representations persist over body rotations

We explored a system that constructs environment-centered frames of reference and coordinates memory for the azimuth of an object in an enclosed space. For one group, we provided two environmental cues (doors): one in the front, and one in the rear. For a second group, we provided two object cues: a front and a rear cue. For a third group, we provided no external cues; we assumed that for this group, their reference frames would be determined by the orthogonal geometry of the floor-and-wall junction that divides a space in half or into multiple territories along the horizontal continuum. Using Huttenlocher, Hedges, and Duncan’s (Psychological Review 98: 352-376, 1991) category-adjustment model (cue-based fuzzy boundary version) to fit the data, we observed different reference frames than have been seen in prior studies involving two-dimensional domains. The geometry of the environment affected all three conditions and biased the remembered object locations within a two-category (left vs. right) environmental frame. The influence of the environmental geometry remained observable even after the participants’ heading within the environment changed due to a body rotation, attenuating the effect of the front but not of the rear cue. The door and object cues both appeared to define boundaries of spatial categories when they were used for reorientation. This supports the idea that both types of cues can assist in environment-centered memory formation.     

Walking reveals trunk orientation bias for visual attention

Our trunks influence where we perform actions in space. Thus, trunk direction may define a region of spacethat is accorded special treatment by the attention system. We investigated conditions under which a trunk orientation bias for attention might be relevant for healthy adults. Three experiments compared visual detection performance for participants standing and walking on a treadmill. Together, the experiments disambiguate the relative contributions of motor activity, motor load, and cognitive load on trunk orientation biases. In Experiment 1, trunk orientation biases (i.e., faster target detection for targets in front of the body midline) were observed in both forward and sideways walking conditions, but not in standing conditions. In Experiment 2, we ruled out the notion that the trunk orientation bias arose from increased motor activity; in fact, the bias was greatest when participants walked at an unusually slow pace. In Experiment 3, we directly compared motor load with cognitive load in a dual-task paradigm; cognitive load influenced overall performance speed, but only motor load produced trunk orientationbias. These results suggest that a trunk orientation bias emerges during walking and motor load conditions.     

The sensorimotor contributions to implicit memory, familiarity, and recollection

The sensorimotor contributions to memory for prior occurrence were investigated. Previous research has shown that both implicit memory and familiarity draw on gains in stimulus-related processing fluency for old, compared with novel, stimuli, but recollection does not. Recently, it has been demonstrated that processing fluency itself resides in stimulus-specific motor simulations or reenactment (e.g., covert pronouncing simulations for words as stimuli). Combining these lines of evidence, it was predicted that stimulus-specific motor interference preventing simulations should impair both implicit memory and familiarity but leave recollection unaffected. This was tested for words as verbal stimuli associated to pronouncing simulations in the oral muscle system (but also for tunes as vocal stimuli and their associated vocal system, Experiment 2). It was found that oral (e.g., chewing gum), compared with manual (kneading a ball), motor interference prevented mere exposure effects (Experiments 1-2), substantially reduced repetition priming in word fragment completion (Experiment 3), reduced the familiarity estimates in a remember-know task (Experiment 5) and in receiver-operating characteristics (Experiment 6), and completely neutralized familiarity measured by self-reports (Experiment 4) and skin conductance responses (Experiment 7), while leaving recollection and free recall unaffected (across Experiments 1-7). This pattern establishes a rare memory dissociation in healthy participants, that is, explicit without implicit memory or recognizing without feeling familiar. Implications for embodied memory and neuropsychology are discussed.     

Memory monitoring and the control of stereotype distortion

We propose a framework for investigating the role of conscious experience in regulating stereotype-based memory distortions. Memory biases are mediated by multiple memory processes, including forms of discriminability and response biases. Different psychological interpretations of these processes depend on how they relate to subjective experiences (e.g., conscious recollection vs. implicit accessibility processes). The ability to control memory distortions, in turn, depends on the psychological meaning attached to these parameters. In Experiment 1 we found that confidence was positively related to discriminability but uncorrelated with stereotype-consistent bias. In Experiment 2 participants were allowed to selectively control when they responded. Because of the asymmetry in monitoring ability, participants were able to increase overall accuracy, but were not able to reduce the stereotype bias. Discussion focuses on the conditions in which subjective experience may provide a valid basis for controlling biases, and when subjective experience may prove deceptive, exacerbating biases.     

Categorical perception of facial expressions: Evidence for a “category adjustment” model

Four experiments probed the nature of categorical perception (CP) for facial expressions. A model based on naming alone failed to accurately predict performance onthese tasks. The data are instead consistentwith an extension of the category adjustment model (Huttenlocher et al., 2000), in which the generation of a verbal code (e.g., "happy") activated knowledge ofthe expression category's range andcentral tendency (prototype) in memory, which was retained as veridical perceptual memory faded.Further support for amemory bias toward the category center came from a consistently asymmetric pattern of within-category errors. Verbal interference in the retention interval selectively removed CP for facial expressions, under blocked, but not under randomized presentation conditions. However, verbal interference at encoding removed CPeven under randomized conditions and these effects were shown to extend even to caricatured expressions, which lie outside the normal range of expression categories.     

Independent operation of implicit working memory under cognitive load

Implicit working memory (WM) has been known to operate non-consciously and unintentionally. The current study investigated whether implicit WM is a discrete mechanism from explicit WM in terms of cognitive resource. To induce cognitive resource competition, we used a conjunction search task (Experiment 1) and imposed spatial WM load (Experiment 2a and 2b). Each trial was composed of a set of five consecutive search displays. The location of the first four displays appeared as per pre-determined patterns, but the fifth display could follow the same pattern or not. If implicit WM can extract the moving pattern of stimuli, response times for the fifth target would be faster when it followed the pattern compared to when it did not. Our results showed implicit WM can operate when participants are searching for the conjunction target and even while maintaining spatial WM information. These results suggest that implicit WM is independent from explicit spatial WM.     

From maps to navigation: The role of cues in finding locations in a virtual environment

In two experiments, participants navigated through a large arena within a virtual environment (VE) to a location encoded in memory from a map. In both experiments, participants recalled locations by navigating through the VE, but in Experiment 2, they additionally recalled the locations on the original map. Two cues were located outside and above the walls of the arena at either north-south locations or east-west locations. The pattern of angular bias was used to infer how the cues affected the creation of spatial categories influencing memory for location in the two tasks. When participants navigated to remembered locations in the VE, two cue-based spatial categories were inferred, with cues serving to demarcate the boundaries of the categories. When participants remembered locations on the original map, two cue-based categories were again formed, but with cues serving as category prototypes. The pattern of results implies that cue-based spatial categorization schemes may be formulated differently at the memory retrieval stage depending on task constraints.     

Perception-action dissociations of a walkable Müller-Lyer configuration

These studies examined the role of spatial encoding in inducing perception-action dissociations in visual illusions. Participants were shown a large-scale Müller-Lyer configuration with hoops as its tails. In Experiment 1, participants either made verbal estimates of the extent of the Müller-Lyer shaft (verbal task) or walked the extent without vision, in an offset path (blind-walking task). For both tasks, participants stood a small distance away from the configuration, to elicit object-relative encoding of the shaft with respect to its hoops. A similar illusion bias was found in the verbal and motoric tasks. In Experiment 2, participants stood at one endpoint of the shaft in order to elicit egocentric encoding of extent. Verbal judgments continued to exhibit the illusion bias, whereas blind-walking judgments did not. These findings underscore the importance of egocentric encoding in motor tasks for producing perception-action dissociations.     

Effects of retrieval practice on conceptual explicit and implicit consumer memory

Two experiments are reported that investigate the effects of retrieval practice on explicit and implicit memory for brand names. In Experiment 1, participants were exposed to a set of brand names pertaining to a range of product categories. Following this, participants practiced retrieving a subset of the brands before taking an explicit or implicit test for the brands. The explicit test, required recall of the brands in response to product category cues. The implicit test required the generation of the first brand names that came to mind. In both tests, prior retrieval produced retrieval‐induced forgetting of the non‐practiced brands. Experiment 2 replicated this effect under conditions designed to reduce explicit contamination. In addition, Experiment 2 found that increasing the amount of retrieval practice also increased the magnitude of retrieval‐induced forgetting on the explicit but not the implicit test. Implications for advertising and marketing are considered. Copyright © 2008 John Wiley & Sons, Ltd.     

The flexible use of inductive and geometric spatial categories

The present study examined the flexibility with which people can adopt different category schemes in the spatial domain. In a location memory task, participants viewed and estimated the locations of four kinds of objects that were spatially grouped by object identity. This identity-based arrangement was either congruent or incongruent with the perceptually based, geometric categories that have been reported in previous research. Four experiments examined the conditions under which these different category schemes are used to inform estimates of locations. The results showed that use of identity information depended on the number of objects to be remembered during a trial: When one or two objects were remembered at a time, only geometric categories affected estimates, but when four objects were to be remembered, both geometric categories and identity groupings affected estimates. As memory load increases, participants rely on additional sources to inform their estimates of location.     

提取干扰对内隐记忆的影响

以往研究多认同内隐记忆不会受到干扰的影响,但主要集中于编码时的干扰不会影响随后的内隐记忆提取成绩,而对于提取时的干扰是否也不会影响内隐记忆成绩仍存在疑义。该文在实验1采用学习-测验范式,通过在提取阶段设置同时干扰任务进一步考察提取干扰与内隐记忆的关系,结果表明提取干扰下并未发现明显的启动效应,即提取干扰破坏了内隐记忆。为进一步探讨内隐记忆的提取干扰效应是否源于记忆与干扰刺激同时呈现所引起的知觉表征竞争,实验2改变了记忆与干扰刺激的呈现顺序,结果表明不论干扰刺激在记忆项目之前或之后呈现,启动效应均受到影响。相比之下,提取干扰对再认成绩的影响并不明显(实验3)。上述结果表明,内隐记忆的提取干扰效应是源于一般认知资源的竞争,在提取过程中任何能够产生认知资源竞争的变量设置都可能会削减内隐测验中的启动效应。     

Performance costs when emotion tunes inappropriate cognitive abilities: implications for mental resources and behavior

Emotion tunes cognition, such that approach-motivated positive states promote verbal cognition, whereas withdrawal-motivated negative states promote spatial cognition (Gray, 2001). The current research examined whether self-control resources become depleted and influence subsequent behavior when emotion tunes an inappropriate cognitive tendency. In 2 experiments, either an approach-motivated positive state or a withdrawal-motivated negative state was induced, and then participants completed a verbal or a spatial working memory task creating conditions of emotion-cognition alignment (e.g., approach/verbal) or misalignment (e.g., approach/spatial). A control condition was also included. To examine behavioral costs due to depleted self-control resources, participants completed either a Stroop task (Stroop, 1935; Experiment 1) or a Black/White implicit association test (IAT; Greenwald, McGhee, & Schwartz, 1998; Experiment 2). Participants in the misalignment conditions performed worse on the Stroop task, and they were worse at controlling their implicit attitude biases on the IAT. Thus, when emotion tunes inappropriate cognitive tendencies for one's current environment, self-control resources become depleted, impairing behavioral control.     

Memory for locations within regions: Spatial biases and visual hemifield differences

Memory for location of a dot inside a circle was investigated with the circle in the center of a computer screen (Experiment 1) or with the circle presented in either the left or the right visual field (Experiment 2). In both experiments, as in Huttenlocher, Hedges, and Duncan’s (1991) study, the task was to relocate the dot by marking the remembered location. When errors in angular and radial estimates were considered separately, it was found that, in both experiments, the angular locations of estimates of the dots’ positions regressed toward different locations inside each quadrant of the circle; the radial locations of the estimates of dots’ positions tended to regress toward locations near the circumference. These variations in the direction of bias appeared to reflect a general shift of estimates toward the upper left arc of the circle. The second experiment replicated the preceding effects but also revealed that the regressions within quadrants of angular values were stronger after right visual field than after left visual field presentations. We interpret the dissociation between visual fields as evidence that memory for categorical spatial relations (Kosslyn, 1987) is more dependent on left-hemisphere than on right-hemisphere processing.     

Working Memory Updating: Load and Binding

In the present study, we aimed to examine how specific objects are updated in working memory. We compared conditions in which contents or content-context bindings from working memory were both encoded and updated (Experiment 1). In addition, for bindings, we manipulated the memory load (i.e., number of contents) to maintain during updating. Results indicated that memory load did not specifically affect the process; rather, the content-context binding (vs. single contents) was critical in determining the increase in response latencies. Results were replicated even in Experiment 2, in which we manipulated the spatial locations of the to-be-recognized probes. Results showed evidence of a potential dissociation between updating of memory contents-only and content-context bindings. In addition, memory load and spatial coherence between phases and probe recognition did not interact with updating performance. Overall, results were taken as a contribution toward mapping the complex nature of the updating mechanism.     

Does priming a specific illness schema result in an attentional information-processing bias for specific illnesses?

OBJECTIVE: To test a hypothesis derived from H. Leventhal, D. Meyer, and D. Nerenz's (1980) commonsense model that people possess implicit schemas for specific illnesses. DESIGN: A 2 (illness vs. neutral shopping prime) x 2 (illness-related vs. control word) mixed design with repeated measures on the second factor. Participants primed for the common cold (Experiment 1) and cardiovascular disease (Experiment 2) were compared with participants receiving a neutral shopping prime on a modified Stroop color naming task. MAIN OUTCOME MEASURES: Attentional bias to illness related words was calculated as the difference between response latencies to illness words and neutral words under the prime conditions. RESULTS: In Experiment 1, participants primed with common cold showed a response bias to words related to the common cold but not to words related to cardiovascular disease. Attentional bias among participants primed for common cold was significantly correlated with explicit illness representations assessed by the Revised Illness Perception Questionnaire. Experiment 2 replicated the findings in a different illness domain. CONCLUSION: Illness-specific illness schemas can be activated.     

From A to Z? Retrieval-induced forgetting of non-verbal information indicates how writing systems can shape memory organisation

We investigated retrieval-induced forgetting of motor sequences in samples of Chinese participants. Retrieval-induced forgetting occurs when selective retrieval of a subset of information stored in memory causes forgetting for the non-retrieved rest. This phenomenon critically depends on the organised storage of separate categories of memory representations. In studies with participants from a Western culture (Germany), a categorization in left- and right-hand movements previously had been supported by letter stimuli based on a spatial mental representation of the Roman alphabet. The same assignment of letters from the beginning or end of the alphabet to motor sequences performed either with the left- or the right-hand did not entail retrieval-induced forgetting in the present study, however (Experiment 1). In Experiment 2, visual features of displaying to-be-learned sequences additionally supported a distinction into left and right. In Experiment 3, learning trials provided verbal category labels. The occurrence of retrieval-induced forgetting in the latter two experiments suggests language-dependent organisation of non-verbal items in memory.     

空间工作记忆负载对真实场景情境提示效应的影响

重复的画面布局能够促进观察者对目标项的搜索 (情境提示效应)。本研究采用双任务范式,分别在视觉搜索任务的学习阶段 (实验2a) 和测验阶段 (实验2b) 加入空间工作记忆任务, 并与单任务基线 (实验1)进行比较, 考察空间工作记忆负载对真实场景搜索中情境线索学习和情境提示效应表达的影响。结果发现: 空间负载会增大学习阶段的情境提示效应量, 同时削弱测验阶段的情境提示效应量, 而不影响情境线索的外显提取。由此可见, 真实场景中情境线索的学习和提示效应的表达均会受到有限的工作记忆资源的影响, 但情境线索提取的外显性不变。