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Memory is an adaptive and flexible system that preferentially stores motivationally relevant information. However, in some cases information that is initially irrelevant can become relevant at a later time. The question arises whether and to what extent the memory system can retroactively boost memories of the initially irrelevant information. Experimental studies in animals and humans have provided evidence for such retroactive memory boosting. Additionally, these studies suggest that retroactive memory enhancement (RME) can be selective to the semantic meaning of the material. Nonetheless, recent experimental work could not replicate these findings, posing the question whether the selective RME effect is reliable. To synthesize the available evidence, we conducted meta-analyses of 14 experiments. Although the classical meta-analytic procedure suggested a small selective RME effect, Cohen's dz = 0.16, when accounting for small-study bias using robust Bayesian meta-analysis the null hypothesis was supported, Cohen's dz = 0.02, BF01 = 3.03. Furthermore strong evidence was found for a bias due to small-study effects, BF10 = 11.39. Together, this calls the reliability of a selective RME effect into question. [ABSTRACT FROM AUTHOR]

Korsakoff's syndrome (KS) is a neuropsychiatric disorder characterized by severe declarative memory disruption. While episodic memory deficits and confabulation are well documented, it remains unclear to what extent semantic memory is compromised in this syndrome. Moreover, how such impairments relate to the capacity for future-oriented thinking remains unknown. Here, we sought to determine the extent to which episodic and semantic forms of past and future thinking are impacted in KS and the interrelationship between different classes of memory in this syndrome. Twenty patients with KS and 17 matched healthy controls took part in this study. We included well-established indices of past and future thinking capacity, enabling us to compare episodic (event-based) versus semantic (nonpersonal knowledge) across past and future conditions. We also included a novel event generation task to probe implausible event simulation (i.e., spending a day on the moon). Our findings revealed marked impairments in KS across all forms of past and future thinking, as well as the generation of episodic details on the implausible event simulation task. Correlation analyses revealed significant associations between implausible event construction and episodic and semantic future thinking in KS; however, no significant associations were found between future thinking performance and confabulation. This study is the first, to our knowledge, to reveal striking impairments in the capacity for past and future thinking across episodic and semantic domains in KS. Our findings resonate with current theoretical perspectives in which the lines between episodic and semantic memory systems are viewed as increasingly blurred. [ABSTRACT FROM AUTHOR]

The present paper describes the Box Task, a paradigm for the computerized assessment of visuospatial working memory. In this task, hidden objects have to be searched by opening closed boxes that are shown at different locations on the computer screen. The set size (i.e., number of boxes that must be searched) can be varied and different error scores can be computed that measure specific working memory processes (i.e., the number of within-search and between-search errors). The Box Task also has a developer’s mode in which new stimulus displays can be designed for use in tailored experiments. The Box Task comes with a standard set of stimulus displays (including practice trials, as well as stimulus displays with 4, 6, and 8 boxes). The raw data can be analyzed easily and the results of individual participants can be aggregated into one spreadsheet for further statistical analyses. [ABSTRACT FROM AUTHOR]

The present study focused on interference in a group of patients with amnesia due to Korsakoff’s syndrome (KS) within the domain of spatial memory. An object-location memory task was used in which participants first learned an array of objects on a computer screen, followed by a reconstruction of the object positions. Next a trial was given in which the same objects were presented only now in different locations. Participants had to place the objects a second time but at the new locations. This was repeated for seven pairs of baseline/interference trials. Both Korsakoff patients and matched controls did worse on the interference trials than on the baseline trials, indicating that it is difficult to relearn new spatial locations for objects that previously were remembered in other locations. When computing relative interference effects (that is the percentage change from baseline in the interference trials), Korsakoff patients were less affected than controls. It is discussed in how far interference depends on the strength of the original memories, which are markedly lower in KS patients. [ABSTRACT FROM AUTHOR]

Half a million bariatric procedures are performed annually worldwide. Our aim was to review the signs and symptoms of Wernicke’s encephalopathy (WE) after bariatric surgery. We included 118 WE cases. Descriptions involved gastric bypass (52%), but also newer procedures like the gastric sleeve. Bariatric WE patients were younger (median = 33 years) than those in a recent meta-analysis of medical procedures (mean = 39.5 years), and often presented with vomiting (87.3%), ataxia (84.7%), altered mental status (76.3%), and eye movement disorder (73.7%). Younger age seemed to protect against mental alterations and higher BMI against eye movement disorders. The WE treatment was often insufficient, specifically ignoring low parenteral thiamine levels (77.2%). In case of suspicion, thiamine levels should be tested and treated adequately with parenteral thiamine supplementation. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore how people use egocentric (i.e., with respect to their body) and allocentric (i.e., with respect to another element in the environment) references in combination with coordinate (metric) or categorical (abstract) spatial information to identify a target element. Participants were asked to memorize triads of 3D objects or 2D figures, and immediately or after a delay of 5 s, they had to verbally indicate what was the object/figure: (1) closest/farthest to them ( egocentric coordinate task); (2) on their right/left ( egocentric categorical task); (3) closest/farthest to another object/figure ( allocentric coordinate task); (4) on the right/left of another object/figure ( allocentric categorical task). Results showed that the use of 2D figures favored categorical judgments over the coordinate ones with either an egocentric or an allocentric reference frame, whereas the use of 3D objects specifically favored egocentric coordinate judgments rather than the allocentric ones. Furthermore, egocentric judgments were more accurate than allocentric judgments when the response was Immediate rather than delayed and 3D objects rather than 2D figures were used. This pattern of results is discussed in the light of the functional roles attributed to the frames of reference and spatial relations by relevant theories of visuospatial processing. [ABSTRACT FROM AUTHOR]

Semantic and phonemic fluency tasks are frequently used to test executive functioning, speed and attention, and access to the mental lexicon. In semantic fluency tasks, subjects are required to generate words belonging to a category (e.g., animals) within a limited time window, whereas in phonemic fluency tasks subjects have to generate words starting with a given letter. Anatomical correlates of semantic and phonemic fluency are currently assumed to overlap in left frontal structures, reflecting shared executive processes, and to be distinct in left temporal and right frontal structures, reflecting involvement of distinct memory processes and search strategies. Definite evidence for this assumption is lacking. To further establish the anatomical correlates of semantic and phonemic fluency, we applied assumption-free voxel-based and region-of-interest-based lesion-symptom mapping in 93 patients with ischemic stroke. Fluency was assessed by asking patients to name animals (semantic), and words starting with the letter N and A (phonemic). Our findings indicate that anatomical correlates of semantic and phonemic fluency overlap in the left inferior frontal gyrus and insula, reflecting shared underlying cognitive processes. Phonemic fluency additionally draws on the left rolandic operculum, which might reflect a search through phonological memory, and the middle frontal gyrus. Semantic fluency additionally draws on left medial temporal regions, probably reflecting a search through semantic memory, and the right inferior frontal gyrus, which might reflect the application of a visuospatial mental imagery strategy in semantic fluency. These findings establish shared and distinct anatomical correlates of semantic and phonemic fluency. [ABSTRACT FROM AUTHOR]

Korsakoff's syndrome (KS) is a chronic neuropsychiatric disorder caused by alcohol abuse and thiamine deficiency. Patients with KS show restricted autonomy due to their severe declarative amnesia and executive disorders. Recently, it has been suggested that procedural learning and memory are relatively preserved in KS and can effectively support autonomy in KS. In the present review we describe the available evidence on procedural learning and memory in KS and highlight advances in memory rehabilitation that have been demonstrated to support procedural memory. The specific purpose of this review was to increase insights in the available tools for successful memory rehabilitation and give suggestions how to apply these tools in clinical practice to increase procedural learning in KS. Current evidence suggests that when memory rehabilitation is adjusted to the specific needs of KS patients, this will increase their ability to learn procedures and their typically compromised autonomy gets enhanced. [ABSTRACT FROM AUTHOR]

The present study investigated haptic spatial orientation processing in deaf signers, hearing sign language interpreters, and hearing controls. Blindfolded participants had to set two bars parallel in the horizontal plane, with either a 2-s or a 10-s delay between inspection of the reference bar and the setting of the test bar. The deaf group outperformed the other two groups which did not differ from each other. Together these results indicate that deaf individuals can better identify the allocentric spatial coordinates of haptically inspected orientations. These results are discussed in terms of the possible neurocognitive consequences of auditory deprivation. [ABSTRACT FROM AUTHOR]

In this study, we investigated the interactions between temporal and spatial information in auditory working memory. In two experiments, participants were presented with sequences of sounds originating from different locations in space and were then asked to recall either their position or their serial order. In Experiment 1, attention during encoding was manipulated by contrasting 'pure' blocks (i.e., location-only or serial-order-only trials) to 'mixed' blocks (i.e., different percentages of spatial and serial-order trials). In Experiment 2, 'pure' blocks were contrasted to blocks in which spatial and serial-order trials were intermixed with a third task requiring a semantic categorization of sounds. Results from both experiments showed that, whereas serial-order recall is linearly affected by the simultaneous encoding of a concurrent feature, the recall of position is mostly unaffected by concurrent feature encoding. Contrastingly, overall performance level was lower for spatial recall than serial recall. We concluded that serial order and location of items appear to be independently encoded in auditory working memory. Serial order is easier to recall, but strongly affected by the processing of concurrent item dimensions, while item location is more difficult to recall, but relatively automatic, as shown by its strong resistance to interfering dimensions in encoding. [ABSTRACT FROM AUTHOR]

This research is about the role of categorical and coordinate spatial relations and allocentric and egocentric frames of reference in processing spatial information. To this end, we asked whether spatial information is firstly encoded with respect to a frame of reference or with respect to categorical/coordinate spatial relations. Participants had to judge whether two vertical bars appeared on the same side ( categorical) or at the same distance ( coordinate) with respect to the centre of a horizontal bar ( allocentric) or with respect to their body midline ( egocentric). The key manipulation was the timing of the instructions: one instruction (reference frame or spatial relation) was given before stimulus presentation, the other one after. If spatial processing requires egocentric/allocentric encoding before coordinate/categorical encoding, then spatial judgements should be facilitated when the frame of reference is specified in advance. In contrast, if categorical and coordinate dimensions are primary, then a facilitation should appear when the spatial relation is specified in advance. Results showed that participants were more accurate and faster when the reference frame rather than the type of spatial relation was provided before stimulus presentation. Furthermore, a selective facilitation was found for coordinate and categorical judgements after egocentric and allocentric cues, respectively. These results suggest a hierarchical structure of spatial information processing where reference frames play a primary role and selectively interact with subsequent processing of spatial relations. [ABSTRACT FROM AUTHOR]

Many reports show that spatial relations between and within objects show differences in hemispheric lateralization. Coordinate, metric relations concerning distances are processed with a right-hemisphere advantage, whereas a left-hemisphere advantage is thought to be related to categorical, abstract relations (Kosslyn, 1987). Kemmerer and Tranel (2000) argued that the left-hemisphere advantage for categorical processing might apply only for verbal spatial categories, however, whereas a right-hemisphere advantage is related to visuospatial categories. To test this idea, we examined categorical processing for stimuli in both verbal and visuospatial formats, with a visual half-field, match-to-sample design. In Experiment 1, we manipulated the format of the second stimulus to compare response patterns for both verbal and visuospatial stimuli. In Experiment 2, we varied the expectancy of the format of the second stimulus, allowing for an assessment of strategy use. The results showed that a left-hemisphere advantage was related to verbal stimulus format only, but not in all conditions. A right-hemisphere advantage was found only with a visuospatial expectancy, visuospatial format, and brief interval. The theory we present to explain these results proposes that the lateralization related to basic categorical processing can be strongly influenced by verbal characteristics and, to some extent, by additional coordinate processing. The lateralization measured in such cases does not represent lateralization related purely to categorical processing, but to these additional effects as well. This stresses the importance of careful task and stimulus design when examining categorical processing in order to reduce the influence of those additional processes. [ABSTRACT FROM AUTHOR]

Spatial memory is crucial to our daily lives and in part strongly depends on automatic, implicit memory processes. This study investigates the neurocognitive basis of conscious and unconscious influences of object–location memory in amnesic patients with Korsakoff’s syndrome ( N = 23) and healthy controls ( N = 18) using a process-dissociation procedure in a computerized spatial memory task. As expected, the patients performed substantially worse on the conscious memory measures but showed even slightly stronger effects of unconscious influences than the controls. Moreover, a delayed test administered after 1 week revealed a strong decline in conscious influences in the patients, while unconscious influences were not affected. The presented results suggest that conscious and unconscious influences of spatial memory can be clearly dissociated in Korsakoff’s syndrome. [ABSTRACT FROM AUTHOR]

The primary purpose of this study was to examine the effects of non-informative vision and visual interference upon haptic spatial processing, which supposedly derives from an interaction between an allocentric and egocentric reference frame. To this end, a haptic parallelity task served as baseline to determine the participant-dependent biasing influence of the egocentric reference frame. As expected, large systematic participant-dependent deviations from veridicality were observed. In the second experiment we probed the effect of non-informative vision on the egocentric bias. Moreover, orienting mechanisms (gazing directions) were studied with respect to the presentation of haptic information in a specific hemispace. Non-informative vision proved to have a beneficial effect on haptic spatial processing. No effect of gazing direction or hemispace was observed. In the third experiment we investigated the effect of simultaneously presented interfering visual information on the haptic bias. Interfering visual information parametrically influenced haptic performance. The interplay of reference frames that subserves haptic spatial processing was found to be related to both the effects of non-informative vision and visual interference. These results suggest that spatial representations are influenced by direct cross-modal interactions; inter-participant differences in the haptic modality resulted in differential effects of the visual modality. [ABSTRACT FROM AUTHOR]

Previous studies have shown that the amplitude of event related brain potentials (ERPs) elicited by a combined audiovisual stimulus is larger than the sum of a single auditory and visual stimulus. This enlargement is thought to reflect multisensory integration. Based on these data, it may be hypothesized that the speeding up of responses, due to exogenous orienting effects induced by bimodal cues, exceeds the sum of single unimodal cues. Behavioral data, however, typically revealed no increased orienting effect following bimodal as compared to unimodal cues, which could be due to a failure of multisensory integration of the cues. To examine this possibility, we computed ERPs elicited by both bimodal (audiovisual) and unimodal (either auditory or visual) cues, and determined their exogenous orienting effects on responses to a to-be-discriminated visual target. Interestingly, the posterior P1 component elicited by bimodal cues was larger than the sum of the P1 components elicited by a single auditory and visual cue (i.e., a superadditive effect), but no enhanced orienting effect was found on response speed. The latter result suggests that multisensory integration elicited by our bimodal cues plays no special role for spatial orienting, at least in the present setting. [ABSTRACT FROM AUTHOR]

The present paper reviews research on a haptic orientation processing. Central is a task in which a test bar has to be set parallel to a reference bar at another location. Introducing a delay between inspecting the reference bar and setting the test bar leads to a surprising improvement. Moreover, offering visual background information also elevates performance. Interestingly, (congenitally) blind individuals do not or to a weaker extent show the improvement with time, while in parallel to this, they appear to benefit less from spatial imagery processing. Together this strongly points to an important role for visual processing mechanisms in the perception of haptic inputs. [ABSTRACT FROM AUTHOR]

The aim of this study was to establish whether spatial attention triggered by bimodal exogenous cues acts differently as compared to unimodal and crossmodal exogenous cues due to crossmodal integration. In order to investigate this issue, we examined cuing effects in discrimination tasks and compared these effects in a condition wherein a visual target was preceded by both visual and auditory exogenous cues delivered simultaneously at the same side (bimodal cue), with conditions wherein the visual target was preceded by either a visual (unimodal cue) or an auditory cue (crossmodal cue). The results of two experiments revealed that cuing effects on RTs in these three conditions with an SOA of 200 ms had comparable magnitudes. Differences at a longer SOA of 600 ms (inhibition of return for bimodal cues, Experiment 1) disappeared when catch trials were included (in Experiment 2). The current data do not support an additional influence of crossmodal integration on exogenous orienting, but are well in agreement with the existence of a supramodal spatial attention module that allocates attentional resources towards stimulated locations for different sensory modalities. [ABSTRACT FROM AUTHOR]

In order to study the influence of intentional and incidental learning conditions on route learning, young adults walked a route through a university building. Half of the participants focused their attention on the route (intentional learning condition), while the other half did not (incidental learning condition). Five tests of spatial knowledge were employed: a route-length-estimation, landmark recognition, landmark ordering, map-drawing and navigation task. The intentional group performed better than the incidental group on the map-drawing and navigation task. No difference between the intentional and incidental group was found on the landmark-recognition and landmark-ordering task. Moreover, the intentional group overestimated the walking distance, while the incidental group underestimated it. These results suggest that route knowledge (landmark recognition and landmark ordering) requires less effortful processing than survey knowledge (developing a map-like representation and actual navigation). [ABSTRACT FROM AUTHOR]

The common view on the interplay between exogenous and endogenous orienting holds that abrupt onsets are not capable of attracting attention when they occur outside the current focus of attention. Does this also apply to sudden irrelevant auditory onsets and when irrelevant visual onsets occur far in the periphery? In addition, does focused attention also reduce the alerting effect of auditory onsets, or vice versa, do highly alerting stimuli distort the attentional state? Crossmodal and unimodal variants of the Posner paradigm were examined in two experiments with targets and irrelevant onsets occurring at 28.3 and 19.3° from fixation. Either centrally presented arrows indicated the forthcoming position of visual targets to be discriminated, or warning cues signaled the likely moment of target occurrence. The targets could be preceded by peripheral auditory or visual onsets that were to be ignored. Crossmodal and unimodal exogenous orienting effects of these irrelevant onsets were observed while participants focused at the relevant side. In addition, no evidence was found that the alerting effect of auditory onsets was dependent on focused attention. Our findings indicate that, at least under the current conditions, neither crossmodal nor unimodal orienting effects of peripheral events dissipate when attention is in a focused state. [ABSTRACT FROM AUTHOR]

Descriptions with a route perspective take the addressee into the environment and give information on the position of objects relative to the changing position of the addressee. In contrast, descriptions with a survey perspective adopt a bird’s-eye view and describe objects with respect to one another. The objective of the present study was to determine whether the perspective of a spatial description influences the extent to which categorical and metric distance is represented. We studied the characteristics of the representations that were constructed from route or survey descriptions with a recognition/priming task and a bird-flight distance comparison task. Spatial priming and symbolic distance effects were present after participants had studied a verbal description. The spatial priming effect indicated that objects in the environment were spatially organized according to some kind of distance (i.e., categorical or metric) in the representation of the listener. Furthermore, this organization was not dependent on whether the objects in a given prime-target relation were explicitly mentioned in the same sentence, or instead had to be inferred from the text. The presence of symbolic distance effects indicated that larger differences in metric distance were easier to compare than smaller differences, which is an effect that is also expected if actual metric distances on a visual map have to be compared. Therefore, further evidence was provided that people are able to create map-like spatial representations of verbal descriptions. We replicated previous findings that route and survey descriptions result in representations from which categorical spatial information is equally available. This study is the first to find evidence that a mental representation, which contains some analog spatial detail (i.e., metric distance), can be constructed from a description with a route perspective. Importantly, it should be noted that a relative advantage for survey descriptions over route descriptions did exist, suggesting that survey descriptions lead to spatial representations with a more fine-grained localization of the objects than route descriptions. [ABSTRACT FROM AUTHOR]

It has been argued that representations of peripersonal space based on haptic input are systematically distorted by egocentric reference frames. Interestingly, a recent study has shown that noninformative vision (i.e., freely viewing the region above the haptic workspace) improves performance on the so-called haptic parallel-setting task, in which participants are instructed to rotate a test bar until it is parallel to a reference bar. In the present study, we made a start at identifying the different sensory integration mechanisms involved in haptic space perception by distinguishing the possible effects of orienting mechanisms from those of noninformative vision. We found that both the orienting direction of head and eyes and the availability of noninformative vision affect parallel-setting performance and that they do so independently: orienting towards a reference bar facilitated the parallel-setting of a test bar in both no-vision and noninformative vision conditions, and noninformative vision improved performance irrespective of orienting direction. These results suggest the effects of orienting and noninformative vision on haptic space perception to depend on distinct neurocognitive mechanisms, likely to be expressed in different modulations of neural activation in the multimodal parietofrontal network, thought to be concerned with multimodal representations of peripersonal space. [ABSTRACT FROM AUTHOR]

Systematic deviations occur when blindfolded subjects set a test bar parallel to a reference bar in the horizontal plane using haptic information (Kappers and Koenderink 1999, Perception 28:781–795; Kappers 1999, Perception 28:1001–1012). These deviations are assumed to reflect the use of a combination of a biasing egocentric reference frame and an allocentric, more cognitive one (Kappers 2002, Acta Psychol 109:25–40). In two experiments, we have examined the effect of delay between the perception of a reference bar and the parallel setting of a test bar. In both experiments a 10-s delay improved performance. The improvement increased with a larger horizontal (left–right) distance between the bars. This improvement was interpreted as a shift from the egocentric towards the allocentric reference frame during the delay period. [ABSTRACT FROM AUTHOR]

Examines implicit memory transfer in patients with dissociative identity disorder (DID). Determination of priming impairments in DID; Demonstration of priming for impossible objects using the sensitive priming index of response times; Normal implicit memory performance displayed by DID patients.

The purpose of the present study was to examine effects of time pressure on mechanisms of speech production and self-monitoring. The most widely accepted monitoring theory (Levelt, 1989) suggests that monitoring proceeds through language perception, that is, speech error detection is primarily based on the parsing of one's own inner and overt speech. Twenty-four subjects described visual networks at two different rates (normal and fast). The time pressure manipulation affected a number of temporal characteristics: the error to cutoff and cutoff to repair times were shorter in the fast than in the normal condition. The results indicate that the monitor adjusts its speed of error detection and repair planning to the faster speech output rate. The time pressure manipulation did not affect the accuracy of error detection. The implications for the perception theory of monitoring are discussed. [ABSTRACT FROM AUTHOR]

Different encoding activities during list learning, such as writing down or reading aloud, have a differential effect on memory performance. It has been argued that intermodal processing, that is, auditory processing of visually presented material and vice versa, results in a better performance than intramodal processing. This has been referred to as the 'translation hypothesis.' In this study, we set out to test the translation hypothesis looking at all four possible experimental conditions using visual and auditory presentation and writing and vocalization as encoding activities. The results show a similar memory performance in all conditions apart from the one in which visually presented words had to be written down. That is, in the only condition in which subjects did not hear the words (either via auditory presentation or via their own vocalization), fewer words were remembered. These findings do not support the translation hypothesis and are more in agreement with previous theoretical proposals regarding long-term modality effects. [ABSTRACT FROM AUTHOR]

Many studies have identified the prefrontal cortex as the brain area that is critical for spatial memory, both in humans and in other primates. Other studies, however, have failed to establish this relation. Therefore, the aim of this paper was to review the literature regarding the role of the human prefrontal lobe in spatial memory. This was done by examining the evidence obtained from neuropsychological patients and from studies using brain-imaging techniques (PET and fMRI). Evidence supporting the notion that the prefrontal cortex is extensively involved in spatial working memory was found. The majority of these studies, however, suggests that frontal-lobe involvement is not related to the type of material that is being processed (e.g., spatial vs. nonspatial), but to process-specific functions, such as encoding and retrieval. Theoretically, these functions could be linked to the central executive within Baddeley's working-memory model, or to recent theories that emphasize the various processes that play a role in working memory. Also, methodological issues were discussed. Further research is needed to enhance our understanding of the precise interaction of domain-specific and general processes. [ABSTRACT FROM AUTHOR]

Different encoding activities during list learning, such as writing down or reading aloud, have a differential effect on memory performance. It has been argued that intermodal processing, that is, auditory processing of visually presented material and vice versa, results in a better performance than intramodal processing. This has been referred to as the "translation hypothesis." In this study, we set out to test the translation hypothesis looking at all four possible experimental conditions using visual and auditory presentation and writing and vocalization as encoding activities. The results show a similar memory performance in all conditions apart from the one in which visually presented words had to be written down. That is, in the only condition in which subjects did not hear the words (either via auditory presentation or via their own vocalization), fewer words were remembered. These findings do not support the translation hypothesis and are more in agreement with previous theoretical proposals regarding long-term modality effects. [ABSTRACT FROM AUTHOR]

Focuses on Object Relocation, a computer program for Windows 95, with which experiments on spatial memory for object locations can be designed, run and analyzed. Graphical and user interface; Stimulus components; Flexibility of the program; Efficient analysis of raw data; Addition of new objects and positions.

Visual processing mechanisms are critically important for perceiving spatial features of our surroundings. This also appears to be so in situations where vision is absent. We will present data from a haptic spatial orientation task (parallel setting of two bars), which show a beneficial effect of a delay between examining the reference bar and setting the test bar, and of noninformative vision (viewing the general setup but not the relevant bar orientations). These results suggest that over time haptic information might be translated into visuospatial representations which support performance. In line with this, blind individuals performed worse than blindfolded sighted participants on comparable haptic spatial tests, in particular congenitally blind did so. Together, these results suggest a recoding of the haptic information into a more abstract spatial representation during processing in working memory. [ABSTRACT FROM AUTHOR]

One of the most consistent findings in the area of cognitive sex differences is that males outperform females on many spatial tasks. One exception seems to be object location memory. On this task, females tend to perform better than males. However, the existing studies have provided quite mixed results and the picture is far from clear. Important moderators not systematically controlled for thus far are encoding context, the way information is retrieved from memory and the multiple component aspect of object location memory. The aim of our research was to investigate—gender differences within and between automatic and controlled encoding (incidental–intentional) and retrieving (explicit–implicit) contexts—if and how memory for objects is related to memory for object locations. Object location memory was assessed by a task in which objects had to be relocated within (pictures of) different rooms. Different encoding contexts were created by varying instructions between subjects. The way in which subjects retrieved the object locations was assessed by means of the Processing Dissociation Procedure developed by Jacoby. A separate object recognition task was conducted in order to measure memory for the objects. In general, females performed better than males on the object location memory task. However, when controlled for object memory, females no longer outperformed males, whereas they did not obtain a higher object recognition score, nor did they have more contextual recollection of the object identities. This indicates that a female advantage probably occurs somewhere else in the process of binding objects to locations. In general, participants had more conscious recollection than unconscious recollection. No effect of encoding context was found, nor any interaction effect of gender, encoding and retrieval context. [ABSTRACT FROM AUTHOR]

The processing of visuospatial information is crucially important for human navigation and spatial memory. It gives us cues for orientation and makes us aware of the spatial relation(s) between ourselves and objects or within and between objects per se. Kosslyn (1987; see also Jager and Postma 2003) has suggested that specific forms of spatial relations (categorical vs coordinate) can be dissociated and are processed through distinct hemispheric networks. It is unclear yet whether these networks develop with age. Hence, in a perceptual divided-visual-field task, in which we also varied the time course in order to measure working memory, children decided whether animal line drawings did or did not change between two consecutive presentations. Using signal detection analyses we calculated sensitivity and bias scores. The results indicated that discrimination sensitivity for spatial transformations improves with age and is higher in the right hemisphere. Furthermore we showed that specific functional lateralization might be a relatively late appearing phenomenon. In contrast to earlier findings, for the older children and adults, a right hemisphere advantage was found for the categorical information. Possible explanations for this latter finding will be discussed. [ABSTRACT FROM AUTHOR]

Finding your way home, remembering where you left the car keys or directing someone to the nearest hospital are examples of highly complex cognitive tasks based on spatial memory and orientation. Without these functions, navigating through daily life would be impossible. Our ability to construct spatial representations of the outside world, and to store them in our memory is likely to underlie many other higher cognitive functions in humans, such as decision-making and planning. Many other animals possess the ability to navigate around their environment but there are certain higher-order features of the human system, such as the ability to communicate spatial information verbally or the ability to switch perspectives, which are uniquely human. This symposium will address how the variety of spatial memory processes is implemented in the human brain, and how it is characterized by differences across species, and within the human species (such as in gender, age and clinical populations). We will start with sketching an evolutionary taxonomy of spatial memory and spatial representations. Next, we will discuss how (certain) spatial abilities might develop during the human ontogeny. An important question of course is how the human brain carries out mental activities such as navigation and perspective taking. We will illustrate this by examples of recent neuroimaging studies on allocentric spatial representations and perspective switches. More insight in to how the human brain deals with spatial information processing can be gathered from neurological cases in which spatial neurological circuits are affected. Another way to understand how spatial representations of the surrounding world are created comes from studying situations in which the sensory input channels are limited, such as in the case of blindness. This sheds light on the supposed supramodality of spatial representations. Finally, the versatility of the human spatial memory system will be illustrated by a closer look at individual differences in humans: how do men and women differ in spatial memory ability?. This symposium derives from a EU funded NEST PATHFINDER research initiative (see ). [ABSTRACT FROM AUTHOR]

Spatial memory is vitally important for many daily life activities. Without it we would be continuously engaged in a laborious search for our keys or wallet, or we could not find our way back home gain. Given this clear ecological relevance, it has been argued that spatial memory would work to a large extent automatically, without conscious control and awareness. In this talk, examples will be given of studies from the Utrecht Psychological Laboratory on implicit and explicit aspects of wayfinding and object location memory in humans. Moreover, possible underlying neuranatomical correlates will be discussed, as revealed by neuropsychological studies. Finally, spatial memory research will be taken outside the laboratory by means of a study on how people lose things in real-life situations. [ABSTRACT FROM AUTHOR]