The effects of aging and dorsal hippocampal lesions: performance on spatial and nonspatial comparable versions of the water maze

Aged intact and young hippocampal-lesioned rats show similar deficits on the spatial water maze. However, this does not necessitate that the source of these deficits in the aged animals is due to hippocampal damage. These water maze deficits may arise from other aging factors such as changes in thermoregulation, muscle fatigue, swim ability, and response to stress. Consequently, it is imperative to examine the performance of aged rats on a comparable nonhippocampal version of this task. Past attempts to develop a hippocampus-independent version of the water maze were confounded because these tasks were easier (i.e., the rats spent much less time swimming in the water) than the spatial versions of the task. The current study examined performance on a hippocampus-independent task comparable in difficulty to the spatial water one. Middle-aged (16-m) and old (25-m) male F344 rats were given sham or dorsal hippocampus lesions and tested on both a spatial and a nonspatial water maze. The middle-aged rats with hippocampal lesions were impaired on the spatial task but not on the nonspatial task. Conversely, aged animals showed a similar impairment on both types of water maze tasks. Additionally, hippocampal lesions exacerbated the age-related impairment on both tasks. These findings indicate that caution must be used when interpreting the results of water maze tasks for aged animals.     

Cognitive spatial processing and the regulation of posture

Subjects performed the Brooks (1967) spatial and nonspatial memory tasks either while sitting or while maintaining a difficult standing balance position. The balance task disrupted spatial but not nonspatial memory performance. Balance steadiness during spatial and nonspatial memory conditions did not differ. These results suggest that cognitive spatial processing may rely on neural mechanisms that are also required for the regulation of posture.     

Perceptual and cognitive processes in time-to-contact estimation: Analysis of prediction-motion and relative judgment tasks

Three classes of task appear to involve time-to-contact (TTC) information: coincidence anticipation (CA) tasks, relative judgment (RJ) tasks, and interceptive actions (IAs). An important type of CA task used to study the perception of TTC is the prediction-motion (PM) task. The question of whether it is possible to study the perceptual processes involved in the timing of IAs using PM and RJ tasks is considered. A revised version of the tau hypothesis is proposed as an account of the perceptual information processing involved in the control of fast IAs. This draws on the distinction between “motor” and “cognitive” visual systems. It is argued that task variables affect whether “cognitive” information processing is involved in performance and can determine whether TTC information is used at all. Evidence is reviewed that suggests that PM and RJ tasks involve cognitive processing. It is argued that target viewing time, TTC at response initiation, amount of practice, and whether there is a period between target disappearance and response are task variables that determine whether cognitive processing will influence responding.     

Spatial working memory load affects counting but not subitizing in enumeration

The present study investigated whether subitizing reflects capacity limitations associated with two types of working memory tasks. Under a dual-task situation, participants performed an enumeration task in conjunction with either a spatial (Experiment 1) or a nonspatial visual (Experiment 2) working memory task. Experiment 1 showed that spatial working memory load affected the slope of a counting function but did not affect subitizing performance or subitizing range. Experiment 2 showed that nonspatial visual working memory load affected neither enumeration efficiency nor subitizing range. Furthermore, in both spatial and nonspatial memory tasks, neither subitizing efficiency nor subitizing range was affected by amount of imposed memory load. In all the experiments, working memory load failed to influence slope, subitizing range, or overall reaction time. These findings suggest that subitizing is performed without either spatial or nonspatial working memory. A possible mechanism of subitizing with independent capacity of working memory is discussed.     

Mental rotation of static and dynamic figures

Previous studies comparing performance on standard (i.e., static) and dynamic spatial test items have concluded that the two item types measure different abilities. Such conclusions about the uniqueness of static and dynamic spatial abilities seem premature, however, since only a limited number of dynamic spatial tasks have been utilized in research and these have differed markedly from their static counterparts. In the present studies, tasks were designed to require a common mental operation (mental rotation) under static and dynamic conditions. Correlations between static and dynamic performance ranged from .80 to .90. This appears to suggest that the emergence of a unique dynamic ability factor depends on the utilization of certain specialized tasks (e.g., arrival time tasks) with mental operations much different than those required by conventional spatial tests. In other words, it is apparently the requirement for different cognitive processes and not the processing of stimulus motion per se that distinguishes performance onsome dynamic tasks from performance on some standard static tasks.     

Fimbria/fornix lesions facilitate the learning of a nonspatial response task

The spatial cognitive map theory of O’Keefe and Nadel (1978) predicts that lesions of the hippocampal system should impair learning on spatial tasks but not learning on nonspatial tasks. However, there is evidence that such lesions can facilitate learning on certain nonspatial tasks. Their theory does not predict such facilitation. Nevertheless, it is reasonable to expect that animals possessing a spatial cognitive map would have an inherent bias to engage a mapping strategy and thus be at a disadvantage on certain nonspatial tasks in comparison with animals without the mapping capacity and bias. In the present study, fimbria/fornix lesions impaired learning on a spatial task, but actually facilitated learning on a nonspatial task of equal difficulty. Thus, brain lesions that interfere with map functioning can facilitate learning on tasks for which a mapping strategy interferes with task solution. The results require a modification of the spatial cognitive map theory.     

Brain activation and deactivation during location and color working memory tasks in 11-13-year-old children

Using functional magnetic resonance imaging (fMRI) and n-back tasks we investigated whether, in 11-13-year-old children, spatial (location) and nonspatial (color) information is differentially processed during visual attention (0-back) and working memory (WM) (2-back) tasks and whether such cognitive task performance, compared to a resting state, results in regional deactivation. The location 0-back task, compared to the color 0-back task, activated segregated areas in the frontal, parietal and occipital cortices whereas no differentially activated voxels were obtained when location and color 2-back tasks were directly contrasted. Several midline cortical areas were less active during 0- and 2-back task performance than resting state. The task-induced deactivation increased with task difficulty as demonstrated by larger deactivation during 2-back than 0-back tasks. The results suggest that, in 11-13-year-old children, the visual attentional network is differently recruited by spatial and nonspatial information processing, but the functional organization of cortical activation in WM in this age group is not based on the type of information processed. Furthermore, 11-13-year-old children exhibited a similar pattern of cortical deactivation that has been reported in adults during cognitive task performance compared to a resting state.     

Mice with targeted genetic reduction of GABA(A) receptor alpha1 subunits display performance differences in Morris water maze tasks

Recent research has begun to demonstrate that specific subunits of GABA(A) receptors may be involved in the normal expression of specific behaviors. The present research used mice with GABA(A) receptors whose alpha1 subunits contained mutations of serine 270 to histidine and leucine 277 to alanine in the TM2 region. The purpose was an attempt to examine the possible role that this particular subunit may have in learning the spatial and nonspatial version of the Morris water maze task. Mutant animals, compared to controls, displayed elevated levels of pool circling in both the spatial task and the nonspatial task. These results suggested that normal performance of the spatial and nonspatial water maze tasks may be dependent upon a natural alpha1 subunit array.     

A MULTILEVEL ANALYSIS OF THE EFFECT OF PROMPTING SELF-REGULATION IN TECHNOLOGY-DELIVERED INSTRUCTION

Two studies were conducted to examine the effect of prompting self-regulation, an intervention designed to improve learning from technology-delivered instruction. In Study 1, trainees who were prompted to self-regulate gradually improved their declarative and procedural knowledge over time, relative to the other conditions, whereas test scores declined over time for trainees who were not prompted to self-regulate. In Study 2, basic performance remained stable over time and strategic performance improved over time for trainees who were prompted to self-regulate, relative to the other conditions, whereas performance declined over time for trainees who were not prompted to self-regulate. Trainees' cognitive ability moderated the effect of the prompts on basic performance and task-specific self-efficacy moderated the effect of the prompts on strategic performance. Prompting self-regulation resulted in stronger performance gains over time for trainees with higher ability or higher self-efficacy. These results demonstrate prompting self-regulation improved performance over time, relative to the other conditions, in both online, work-related training and laboratory settings. The results are consistent with theory suggesting self-regulation is a dynamic process that has a gradual effect on performance and highlight the importance of using a within-subjects design in self-regulation research.     

Lesions of the rat postsubiculum impair performance on spatial tasks.

Previous studies have identified a population of neurons in the postsubiculum that discharge as a function of the rat's head direction in the horizontal plane (Taube, Muller, & Ranck, 1990a). To assess the contribution of these cells in spatial learning, Long-Evans rats were tested in a variety of spatial and nonspatial tasks following bilateral electrolytic or neurotoxic lesions of the postsubiculum. Compared to unlesioned control animals, lesioned animals were impaired on two spatial tasks, a radial eight-arm maze task and a Morris water task, although the performance scores of both lesion groups improved over the course of behavioral testing. In contrast, lesioned animals were unimpaired on two nonspatial tasks, a cued version of the water maze task and a conditioned taste-aversion paradigm. In addition, lesioned animals showed transient hyperactivity in an open-field activity test. These results support the concept that neurons in the postsubiculum are part of a neural network involved in the processing of spatial information.     

Team Perceived Trustworthiness in a Complex Military Peacekeeping Simulation

Antecedents to trust (propensity to trust, perceived trustworthiness) and trust behaviors were examined in relation to team performance in a complex eight-mission military peacekeeping simulation. Teams were colocated or distributed and stayed in the same or transferred to a different context at task transfer. In Experiment 1, an ability and competence factor accounted for most of the variance in perceived trustworthiness and greater perceptions of teammates' abilities/competences predicted posttransfer performance. One's perception of how others perceived one's ability/competence increased over missions. In Experiment 2, propensity to trust did not predict performance; however, trust in others' and one's own ability/competence and trust behaviors predicted performance. At task and/or context transfer, teams produced more monitoring and less cooperating language in their communication.     

The effects of collaboration and punishment on prospective memory performance in a group setting

Remembering to perform a delayed intention is termed prospective memory (PM). Often delayed intentions are shared by more than one person; however, there is a dearth of studies examining PM in social settings. We aimed to investigate whether the potential consequences of one's behavior across diverse group settings influence PM performance in event‐ and time‐based tasks. A total of 207 participants were randomly allocated to either an individual, collaborative, or collaborative plus penalty motivation condition and were tested in a 2‐ or 3‐person setting. For the time‐based PM task, participants responded less timely in the individual motivation condition, whereas there was no difference between the collaborative motivation conditions. No significant effects were found for motivation condition on the event‐based task or for group size on PM performance. Analyses of ongoing task performance revealed that participants' attention allocation policies change depending on how individuals prioritize the ongoing and PM tasks.     

Task Importance Effects on Prospective Memory Strategy Use

Mnemonic strategies generally improve prospective memory (PM) performance. However, little is known about why people use such strategies. In the Motivational‐Cognitive Prospective Memory model, task importance is thought to influence performance via multiple mechanisms, including increased strategy use. Our main purpose was to test this mechanism: higher PM task importance was hypothesized to cause greater strategy use. We also tested whether importance would specifically increase the use of more effective (external) strategies. Participants reported their strategy use for two hypothetical PM tasks. As predicted, they listed more strategies for more important tasks. This result demonstrates one mechanism for motivational effects in early phases of the task. We found weaker support for the prediction that participants would selectively increase their use of better strategies for more important tasks. This finding supports a relatively pessimistic view of meta‐memory in PM, at least when it comes to modulating one's use of dependable strategies. Copyright © 2013 John Wiley & Sons, Ltd.     

The Relation Between Experience and Spatial Performance in Men and Women

The purpose of the present study was to test the hypothesis that environmental factors affect the magnitude of gender differences in spatial performance only when the tasks used are susceptible to the influence of such factors. Two hundred and ninety White middle-class undergraduate students (165 females, 125 males) completed the Vandenberg and Kuse Mental Rotations Test (MRT), a paper and pencil version of the Water Level Task (WLT), and toys and sports preference questionnaires. Results revealed that males outperformed females on both spatial tests. In addition, a main effect of toys preference showed that participants with a spatial toys preference outperformed those with a nonspatial preference on both the MRT and the WLT. This main effect was qualified by an interaction between this factor and gender. The interaction was found only on the WLT and showed that gender differences were only significant in participants with a nonspatial preference. An interaction of sports preference and gender was also observed. This interaction revealed that, in contrast to what was obtained with toys, gender differences on both spatial tests were significant only in participants with a spatial sports preference. Implications of these findings with regard to the development of gender differences in spatial abilities are discussed.     

Effects of individual housing and stressor exposure upon the acquisition of watermaze escape

The watermaze tasks of R.G.M. Morris (1981, Learning and Motivation, 12, 239–260) have been used to study the biological bases of spatial learning and memory in rats. These tasks enable the specific study of spatial learning by contrasting performance on two escape tasks. Both tasks allow a rat to escape from a pool of cool water by locating a small escape platform. They differ in the use of a plainly visible platform with varying location in the nonspatial task, versus a hidden platform with constant location in the spatial task. Rats learn to locate both kinds of platform with impressive and nearly equal speed. We report that while rats housed in groups show fast and reproducible acquisition of these tasks, rats housed individually show a gradual decrease in acquisition performance of both spatial and nonspatial tasks. This deficit is detectable after 2 or 3 weeks of isolation, and continues to increase in severity thereafter. The deficit is reversible by a brief period of group housing, by episodic exposure to loud noise, and by episodic restraint. The efficacy of these corrective treatments declines when isolation is prolonged beyond 3 weeks. These findings are interpreted as indicating an abnormality in stress responsiveness in the individually housed animals. The implications of these findings for experiments studying watermaze acquisition in individually housed animals are examined.     

Geometrical illusions can affect time-to-contact estimation and mimed prehension

Results indicate that under some conditions the Sander parallelogram illusion can affect time-to-contact (TTC) estimation in a prediction-motion (PM) task and in an interceptive action (IA). The illusion also affected mimed manual prehension. The implication is that the timing of responses in the PM and IA tasks may involve an estimate of TTC that is based on the perceived dimensions of the environment. Further research is warranted in the development of models of perceived collision and of visually guided actions.     

Relationships between three auditory inspection time tasks and processing speed

This study investigated the relationship between a spatial auditory inspection time task and previous versions of AIT, as well as the relationships of these tasks with visual inspection time (VIT) and general speediness (Gs). A total of 96 university undergraduates (age mean (M) = 20.0 years, standard deviation (SD) = 4.0 years) completed three AIT tasks, VIT, auditory reaction time (ART) and visual reaction time (VRT), and two Gs marker tests. Auditory inspection time‐spatial (AIT‐S) did not relate to VIT, but it did relate to the Gs marker tests. It also loaded moderately on a Gs factor along with VIT. Neither of the alternate AIT tasks showed any consistent relationships to reaction time (RT) or Gs measures. The AIT‐S task did, however, share substantial variance with its predecessors, suggesting that performance on all AIT tasks relies to some extent on similar processes. Further research is required to determine the nature of these processes.     

The role of spatial working memory in visual search efficiency

Many theories have proposed that visual working memory plays an important role in visual search. In contrast, by showing that a nonspatial working memory load did not interfere with search efficiency, Woodman, Vogel, and Luck (2001) recently proposed that the role of working memory in visual search is insignificant. However, the visual search process may interfere with spatial working memory. In the present study, a visual search task was performed concurrently with either a spatial working memory task (Experiment 1) or a nonspatial working memory task (Experiment 2). We found that the visual search process interfered with a spatial working memory load, but not with a nonspatial working memory load. These results suggest that there is a distinction between spatial and nonspatial working memory in terms of interactions with visual search tasks. These results imply that the visual search process and spatial working memory storage require the same limited-capacity mechanisms.     

Visuospatial working memory and mental representation of spatial descriptions

The purpose of the present research is to investigate whether different components of working memory (WM) are involved in processing spatial and nonspatial texts. The interference effects of two concurrent tasks on comprehension and recall of two kinds of text were investigated in two experiments. Each participant listened to a spatial and a nonspatial text, with one of two concurrent tasks: articulatory suppression or spatial tapping. The dependent variables in Experiment 1 were accuracy of recall and verification of information inferred from the texts. In Experiment 2 response times in the verification task were also considered. Results support the hypothesis that verbal and spatial components of working memory are differentially involved in the comprehension and memory of spatial and nonspatial texts, with a selective interference effect of the spatial concurrent task on the spatial text and an interference effect of the verbal concurrent task on both the spatial and nonspatial texts. These effects emerged for recall, sentence verification, and response times. Our findings confirm previous results showing that the verbal component of working memory is involved in the process of text comprehension and memory. In addition, they show that visuospatial working memory is involved, in so far as the text conveys visuospatial information.