Do humans integrate routes into a cognitive map? Map- versus landmark-based navigation of novel shortcuts

Do humans integrate experience on specific routes into metric survey knowledge of the environment, or do they depend on a simpler strategy of landmark navigation? The authors tested this question using a novel shortcut paradigm during walking in a virtual environment. The authors find that participants could not take successful shortcuts in a desert world but could do so with dispersed landmarks in a forest. On catch trials, participants were drawn toward the displaced landmarks whether the landmarks were clustered near the target location or along the shortcut route. However, when landmarks appeared unreliable, participants fell back on coarse survey knowledge. Like honeybees (F. C. Dyer, 1991), humans do not appear to derive accurate cognitive maps from path integration to guide navigation but, instead, depend on landmarks when they are available.     

Learning strategy is influenced by trait anxiety and early rearing conditions in prepubertal male, but not prepubertal female rats

Rodents solve dual-solution tasks that require navigation to a goal by adopting either a hippocampus-dependent place strategy or a striatum-dependent stimulus-response strategy. A variety of factors, including biological sex and emotional status, influence the choice of learning strategy. In these experiments, we investigated the relationship between learning strategy and anxiety level in male and female rats prior to the onset of puberty, before the activational effects of gonadal hormones influence these processes. In the first experiment, prepubertal male rats categorized as high in trait anxiety at 26days of age exhibited a bias toward stimulus-response strategy at 28days of age, whereas age-matched females exhibited no preference in strategy regardless of anxiety level. In the second experiment, male and female rats were separated from their dams for either 15 or 180min per day during the first 2weeks of life and tested on a battery of anxiety and cognitive tasks between 25 and 29days of age. Prolonged maternal separations for 180min were associated with impaired spatial memory on a Y-maze task in both prepubertal males and females. Furthermore, prolonged maternal separations were linked to elevated anxiety and a bias for stimulus-response strategy in prepubertal males but not females. Alternatively, brief separations from dams for 15min were associated with intact spatial memory, lower levels of anxiety, and no preference for either learning strategy in both sexes. These results provide evidence of sex-specific effects of trait anxiety and early maternal separation on the choice of learning strategy used by prepubertal rodents.     

Sex differences in dogs’ social learning of spatial information

We used a modified version of the Do as I Do paradigm to investigate dogs’ preference and flexibility in the acquisition of different types of spatial information in social learning situations. When required to match the location of the demonstration, dogs (N = 16) preferentially relied on allocentric information, i.e., the relationship between the location of the demonstration and the various objects surrounding it. However, when allocentric cues were inadequate to solve the task, dogs learned to rely on egocentric information, i.e., the direction—left/right—taken by the human demonstrator. The ease of resorting to the non-preferred egocentric strategy was sex-dependent with males acquiring the egocentric strategy in fewer trials than females. This study shows that dogs rely preferentially on allocentric cues when recalling socially acquired spatial information. However, they are impressively flexible in switching to egocentric strategies according to the task requirements. Whether preference for the allocentric strategy in processing spatial information is embedded in the nature of social learning or restricted to our paradigm is an open question. This study also supports the idea that sex differences in cognitive domains are widespread among mammals and calls for further investigations aimed at shedding light on the evolution, function and mechanisms of such differences.     

Keeping track of where we are: Spatial working memory in navigation

Spatial working memory (WM) seems to include two types of spatial information: locations and relations. However, this distinction has been based on small-scale tasks. Here, we used a virtual navigation paradigm to examine whether WM for locations and relations applies to the large-scale spatial world. We found that navigators who successfully learned two routes and also integrated them were superior at maintaining multiple locations and multiple relations in WM. However, over the entire spectrum of navigators, WM for spatial relations, but not locations, was specifically predictive of route integration performance. These results lend further support to the distinction between these two forms of spatial WM and point to their critical role in individual differences in navigation proficiency.     

Flexible route selection by pigeons (Columba livia) on a computerized multi-goal navigation task with and without an "obstacle"

The ability to select efficient routes while reaching several locations, in situations addressed as the "traveling salesperson problem (TSP)", seems to play an important role in the lives of nonhuman species as well as humans. One of our previous studies with pigeons (Columba livia) used different variations of computerized navigation tasks to move a target to one or more goals, and showed that the birds consistently exhibited tendencies to visit the nearest goal first (Miyata & Fujita, 2010). Is this inflexible tendency consistent across all situations, or is it abandoned if it leads to a nonefficient strategy? The present study compared pigeons' route selection strategies in two-goal navigation tasks with and without having an L-shaped line as an obstacle barrier between the starting location of the target and the nearer goal. The pigeons frequently started by visiting the nearer goal in trials with no obstacles, whereas in trials having obstacles the birds often visited the farther goal first. For the detour trials with obstacles, the birds started from visiting the farther goal significantly more often than chance, even though disparity between the two traveling sequences was relatively small. The data demonstrated a case in which a tendency to visit the nearest goal was flexibly abandoned when the route required a detour behavior. Detailed analyses of the movement paths further suggest that the pigeons made decisions to choose a farther goal during the initial few steps, although a past history of reinforcement to avoid the barrier might have guided the birds' behavior.     

Landmarks as beacons and associative cues: Their role in route learning

Relatively little is known about how people use the landmarks in their environment to learn routes. Landmarks are commonly regarded as associative cues--stimuli that enable recall of directional responses that lead closer to the navigator's goal. We contrast the function of landmark as associative cue with that of a beacon-a landmark near enough to a goal that moving toward it leads the navigator closer to his or her goal. In five experiments, participants learned a route through a simple desktop virtual environment. In the first three experiments, routes were learned better when their landmarks served as beacons than as associative cues. Two additional experiments showed that the acquired route knowledge depends on the function that landmarks serve during learning. Beacon-based route knowledge is less enduring and relatively less likely to involve knowledge of directions in the environment than is the route knowledge formed from landmarks that serve as associative cues.     

Rats take correct novel routes and shortcuts in an enclosed maze

In 3 experiments, rats were allowed to travel selected routes along the internal alleys of a cross-maze that led from one distinctive end box to another. The maze and procedures used were designed to control the rats' ability to use intrinsic and extrinsic cues to their location in the maze; thus, only the internal geometry of the maze could be learned and used to travel between one end box and another. After an initial exploration phase, rats were given novel routes and shortcut tests that involved peripheral alleys not before traveled. Rats chose the correct novel path or shortcut significantly above chance on some tests in Experiments 1 and 2 and significantly better than a control group in Experiment 3. The findings suggest that rats were able to compute novel routes and shortcuts within the maze on the basis of limited experience with the internal geometry of the maze.     

Sex differences in the lateralization of spatial abilities: a spatial component analysis of extreme group scores

Sex differences in the cerebral lateralization of two discrete components of spatial processing were investigated in high and low ability males and females using the dual-task paradigm. In the first phase of the experiment, the results indicated a pattern of right hemispheric control for a spatial visualization component, regardless of sex and ability level. In the processing of the spatial orientation component of spatial ability, high ability males and females showed left hemispheric lateralization, whereas low ability males and females displayed right hemispheric control. In the second phase of this study, it was observed that high ability females and low ability males may use a verbal mediation strategy in processing spatial visualization tasks. No verbal mediation effects were found for the spatial orientation component.     

Humans do not switch between path knowledge and landmarks when learning a new environment

Using a metric shortcut paradigm, we have found that like honeybees (Dyer in Animal Behaviour 41:239–246, 1991), humans do not seem to build a metric “cognitive map” from path integration. Instead, observers take novel shortcuts based on visual landmarks whenever they are available and reliable (Foo, Warren, Duchon, & Tarr in Journal of Experimental Psychology-Learning Memory and Cognition 31(2):195–215, 2005). In the present experiment we examine whether humans, like ants (Wolf & Wehner in Journal of Experimental Biology 203:857–868, 2000), first use survey-type path knowledge, built up from path integration, and then subsequently shift to reliance on landmarks. In our study participants walked in an immersive virtual environment while head position and orientation were recorded. During training, participants learned two legs of a triangle with feedback: paths from Home to Red and Home to Blue. A configuration of colored posts surrounded the Red location. To test reliance on landmarks, these posts were covertly translated, rotated, or left unchanged during six probe trials. These probe trials were interspersed during the training procedure to measure changes over learning. Dependence on visual landmarks was immediate and sustained during training, and no significant learning effects were observed other than a decrease in hesitation time. Our results suggest that while humans have at least two distinct navigational strategies available to them, unlike ants, a computationally-simpler landmark strategy dominates during novel shortcut navigation.     

Differences in spatial knowledge acquired from maps and navigation

Models of the spatial knowledge people acquire from maps and navigation and the procedures required for spatial judgments using this knowledge are proposed. From a map, people acquire survey knowledge encoding global spatial relations. This knowledge resides in memory in images that can be scanned and measured like a physical map. From navigation, people acquire procedural knowledge of the routes connecting diverse locations. People combine mental simulation of travel through the environment and informal algebra to compute spatial judgments. An experiment in which subjects learned an environment from navigation or from a map evaluates predictions of these models. With moderate exposure, map learning is superior for judgments of relative location and straight-line distances among objects. Learning from navigation is superior for orienting oneself with respect to unseen objects and estimating route distances. With extensive exposure, the performance superiority of maps over navigation vanishes. These and other results are consonant with the proposed mechanisms.     

Sex differences in a human analogue of the Radial Arm Maze: the "17-Box Maze Test"

This study investigated sex differences in spatial memory using a human analogue of the Radial Arm Maze: a revision on the Nine Box Maze originally developed by called the 17-Box Maze Test herein. The task encourages allocentric spatial processing, dissociates object from spatial memory, and incorporates a within-participants design to provide measures of location and object, working and reference memory. Healthy adult males and females (26 per group) were administered the 17-Box Maze Test, as well as mental rotation and a verbal IQ test. Females made significantly fewer errors on this task than males. However, post hoc analysis revealed that the significant sex difference was specific to object, rather than location, memory measures. These were medium to large effect sizes. The findings raise the issue of task- and component-specific sexual dimorphism in cognitive mapping.     

Sex differences in duration judgments: A meta-analytic review

We quantitatively reviewed human sex differences in the magnitude and variability of duration judgments. Data from 4,794 females and 4,688 males yielded 87 effect size estimates of magnitude and 28 of variability. The overall sex difference in duration judgment magnitude was small but statistically significant. It was moderated by whether study participants knew in advance (prospective paradigm) or only later (retrospective paradigm) that they would be required to judge duration. Although prospective judgments showed no overall sex effect, some levels of moderator variables showed a small but statistically significant effect. Retrospective judgments showed a larger subjective-to-objective duration ratio for females than for males, and several variables moderated this effect. Females' judgments also showed more intersubject variability than did males' judgments. Relative to males, females sustain attention to time more in the prospective paradigm and have better episodic memory in the retrospective paradigm.     

Nothing But Stereotypes? Negligible Sex Differences Across Creativity Measures in Science,Arts, and Sports Adolescent High Achievers

Previous research has focused on understanding when, why, and how sex differences in creativity occur, as results vary across samples, measures, and methodologies. In the current study we investigated sex differences in creativity among 984 high achieving adolescents in three expertise areas: Sciences, Arts, and Sports. Eight creativity indicators were analyzed: Alternative uses task (AUT) fluency; creative self-efficacy (CSE); intraindividual strengths (difference between CSE and AUT Fluency); five self-reported creativity scales: Self/everyday, scholarly, performance, mechanical/scientific, artistic. The results showed negligible sex differences ( $n_{\mathrm{p}}^2$ = .01), with females performing better in AUT Fluency and males self-rating their CSE higher. No sex differences were found in self/everyday, scholarly and performance creativity. Males self-rated their mechanical/scientific creativity ( $n_{\mathrm{p}}^2$ = .06) higher than females; while females self-rated their artistic creativity ( $n_{\mathrm{p}}^2$ = .02) higher in comparison to males. Our results extend the existing literature by finding negligible sex differences in adolescent expert groups. However, some stereotypical differences emerged, for example, females with Sciences expertise rated their mechanical/scientific creativity lower than males with and even without Sciences expertise. Results call for further investigation into the links between sex differences, expertise, and specific creativity domains.     

Female aggression as a response to sexual jealousy: A sex role reversal?

Sexual jealousy can be interpreted as a strategy which serves to retain the partner and defend exclusive sexual relationships. Because of the asymmetry in paternity confidence, it should be a more important strategy for males than for females. Indeed, male sexual jealousy is apparently a cross-cultural phenomenon and is often the proximate cause of violence against the female partner. The objective of this study was to investigate through self-report whether male “victims” of partner infidelity are expected to react more aggressively than female “victims,” how subjects themselves say they would react to a partner's infidelity, and whether these expectations vary across the sexes. Contrary to our predictions, subjects expected females more than males to react aggressively and revengefully when confronted with infidelity. These expectations were mainly sustained by the female subjects. Females were also more likely than males to declare that they themselves would verbally and physically abuse the partner. In addition, female subjects anticipated that they would cry, feign indifference, and try to look attractive and cool. Males were more likely than females to report that they would get drunk. Our results on aggressive reactions represent a departure from traditional sex roles. It is argued that emancipatorial development, as well as the levelling influence of contraceptives on the sexes' parental certainty, have triggered this change in sex roles. © 1993 Wiley-Liss, Inc.     

Sex differences in pain

Are there sex differences in pain? For experimentally delivered somatic stimuli, females have lower thresholds, greater ability to discriminate, higher pain ratings, and less tolerance of noxious stimuli than males. These differences, however, are small, exist only for certain forms of stimulation and are affected by many situational variables such as presence of disease, experimental setting, and even nutritive status. For endogenous pains, women report more multiple pains in more body regions than men. With no obvious underlying rationale, some painful diseases are more prevalent among females, others among males and, for many diseases, symptoms differ between females and males. Sex differences in attitudes exist that affect not only reporting, coping, and responses to treatment, but also measurement and treatment. So many variables are operative, however, that the most striking feature of sex differences in reported pain experience is the apparent overall lack of them. On the other hand, deduction from known biological sex differences suggests that these are powerful sex differences in the operation of pain mechanisms. First, the vaginal canal provides an additional route in women for internal trauma and invasion by pathological agents that puts them at greater risk for developing hyperalgesia in multiple body regions. Second, sex differences in temporal patterns are likely to give rise to sex differences in how pain is "learned" and stimuli are interpreted, a situation that could lead to a greater variability and wider range of pains without obvious peripheral pathology among females. Third, sex differences in the actions of sex hormones suggest pain-relevant differences in the operation of many neuroactive agents, opiate and nonopiate systems, nerve growth factor, and the sympathetic system. Thus, while inductive analysis of existing data demonstrate more similarities than differences in pain experience between females and males, deductive analysis suggests important operational sex differences in its production.     

The role of cuticular pheromones in courtship conditioning of Drosophila males

Courtship conditioning is an associative learning paradigm in Drosophila melanogaster, wherein male courtship behavior is modified by experience with unreceptive, previously mated females. While the training experience with mated females involves multiple sensory and behavioral interactions, we hypothesized that female cuticular hydrocarbons function as a specific chemosensory conditioned stimulus in this learning paradigm. The effects of training with mated females were determined in courtship tests with either wild-type virgin females as courtship targets, or with target flies of different genotypes that express distinct cuticular hydrocarbon (CH) profiles. Results of tests with female targets that lacked the normal CH profile, and with male targets that expressed typically female CH profiles, indicated that components of this CH profile are both necessary and sufficient cues to elicit the effects of conditioning. Results with additional targets indicated that the female-specific 7,11-dienes, which induce naive males to court, are not essential components of the conditioned stimulus. Rather, the learned response was significantly correlated with the levels of 9-pentacosene (9-P), a compound found in both males and females of many Drosophila strains and species. Adding 9-P to target flies showed that it stimulates courting males to attempt to copulate, and confirmed its role as a component of the conditioned stimulus by demonstrating dose-dependent increases in the expression of the learned response. Thus, 9-P can contribute significantly to the conditioned suppression of male courtship toward targets that express this pheromone.     

Strain and sex differences on olfactory discrimination learning in C57BL/6J and DBA/2J inbred mice (Mus musculus)

In this study, the authors explored potential strain and sex differences in nonspatial cognitive ability. Beginning around 90 days of age, male and female C57BL/6J (C57) and DBA/2J (DBA) inbred mice (Mus musculus) were tested on a task of simple odor discrimination learning with 3 repeated reversals. Males learned the task more readily than females, and DBA mice learned the task more readily than C57 mice. All differences became evident after repeated testing. Similarity of perseveration measures indicated the differences were not due to inhibitory deficits. Instead, a phase analysis localized differences to a transitional period of reversal learning. Females increased transitional errors that more likely indicated adaptive sampling strategies than memory failures. C57 females used this strategy indiscriminately, but DBA females sampled as a function of environmental uncertainty.     

Applying multimedia learning theory to map learning and driving navigation

The effects of multimedia instructional materials on map learning and subsequent navigation were examined. Participants studied visual and/or verbal driving directions presented simultaneously, sequentially, or exclusively. Memory recall for the studied information was tested, and participants then attempted to navigate the studied routes as well as a novel route in a driving simulator. Dual modality materials with oral narrative directions and a visual map produced significantly superior performance for recall, navigational accuracy, and number of destinations reached than presentation in either modality alone. The presence of a map facilitated route recall but not subsequent ability to navigate routes in the simulator. Map-first dual modality sequential presentation enhanced wayfinding efficiency on the novel route compared to narration-first sequential presentation. Simultaneous presentation of dual modality materials allowed more destinations to be reached compared with sequential presentation. The results demonstrate that multimedia instructional materials can facilitate map learning and driving navigation, extending the applications of multimedia learning theory to this novel domain.