The well-worn route revisited: Striatal and hippocampal system contributions to familiar route navigation.

Classic research has shown a division in the neuroanatomical structures that support flexible (e.g., short-cutting) and habitual (e.g., familiar route following) navigational behavior, with hippocampal-caudate systems associated with the former and putamen systems with the latter. There is, however, disagreement about whether the neural structures involved in navigation process particular forms of spatial information, such as associations between constellations of cues forming a cognitive map, versus single landmark-action associations, or alternatively, perform particular reinforcement learning algorithms that allow the use of different spatial strategies, so-called model-based (flexible) or model-free (habitual) forms of learning. We sought to test these theories by asking participants (N = 24) to navigate within a virtual environment through a previously learned, 9-junction route with distinctive landmarks at each junction while undergoing functional magnetic resonance imaging (fMRI). In a series of probe trials, we distinguished knowledge of individual landmark-action associations along the route versus knowledge of the correct sequence of landmark-action associations, either by having absent landmarks, or "out-of-sequence" landmarks. Under a map-based perspective, sequence knowledge would not require hippocampal systems, because there are no constellations of cues available for cognitive map formation. Within a learning-based model, however, responding based on knowledge of sequence would require hippocampal systems because prior context has to be utilized. We found that hippocampal-caudate systems were more active in probes requiring sequence knowledge, supporting the learning-based model. However, we also found greater putamen activation in probes where navigation based purely on sequence memory could be planned, supporting models of putamen function that emphasize its role in action sequencing.

The effects of spatial stability and cue type on spatial learning: Implications for theories of parallel memory systems.

Some theories of spatial learning predict that associative rules apply under only limited circumstances. For example, learning based on a boundary has been claimed to be immune to cue competition effects because boundary information is the basis for the formation of a cognitive map, whilst landmark learning does not involve cognitive mapping. This is referred to as the cue type hypothesis. However, it has also been claimed that cue stability is a prerequisite for the formation of a cognitive map, meaning that whichever cue type was perceived as stable would enter a cognitive map and thus be immune to cue competition, while unstable cues will be subject to cue competition, regardless of cue type. In experiments 1 and 2 we manipulated the stability of boundary and landmark cues when learning the location of two hidden goals. One goal location was constant with respect to the boundary, and the other constant with respect to the landmark cues. For both cue types, the presence of distal orientation cues provided directional information. For half the participants the landmark cues were unstable relative to the boundary and orientation cues, whereas for the remainder of the participants the boundary was unstable relative to landmarks and orientation cues. In a second stage of training, all cues remained stable so that both goal locations could be learned with respect to both landmark and boundary information. According to the cue type hypothesis, boundary information should block learning about landmarks regardless of cue stability. According to the cue stability hypothesis, however, landmarks should block learning about the boundary when the landmarks appear stable relative to the boundary. Regardless of cue type or stability the results showed reciprocal blocking, contrary to both formulations of incidental cognitive mapping. Experiment 3 established that the results of Experiments 1 and 2 could not be explained in terms of difficulty in learning certain locations with respect to different cue types. In a final experiment, following training in which both landmarks and boundary cues signalled two goal locations, a new goal location was established with respect to the landmark cues, before testing with the boundary, which had never been used to define the new goal location. The results of this novel test of the interaction between boundary and landmark cues indicated that new learning with respect to the landmark had a profound effect on navigation with respect to the boundary, counter to the predictions of incidental cognitive mapping of boundaries.

Feasibility and Acceptability of 'VitaVillage': A Serious Game for Nutrition Education.

Computer games have previously been used to improve nutrition knowledge in children. This paper describes the acceptability and feasibility of a serious game, "VitaVillage", for improving child nutrition knowledge. VitaVillage is a farming-style game in which the player undertakes quests and completes questions aimed at increasing several aspects of nutrition and healthy eating knowledge. Children aged 9-12 years in two primary schools (control vs. intervention) completed a nutrition knowledge questionnaire at baseline (T1) and after 1 week (T2). Participants at the intervention school (n = 75) played VitaVillage for 20 minutes on two occasions. Control participants (n = 94) received no nutrition education. Likeability question scores and written feedback from intervention participants was reported qualitatively. Paired sample t-tests were used to compare T1 and T2 nutrition knowledge changes between control and intervention participants. Engagement with VitaVillage improved children's overall nutrition knowledge (Mean increase of 2.25 points between T1 and T2, Standard Deviation (SD) 6.31, p = 0.035) compared to controls. The game was liked overall (mean score 77 (SD 24.6) on scale of 0-100) and positive feedback was given. Results indicate that VitaVillage has the potential to be successful as a nutrition education tool. In the future, VitaVillage's content and gameplay will be revised, extended and evaluated for its long-term impact on eating behaviour and knowledge changes.

ServAR: An augmented reality tool to guide the serving of food.

BACKGROUND: Accurate estimation of food portion size is a difficult task. Visual cues are important mediators of portion size and therefore technology-based aids may assist consumers when serving and estimating food portions. The current study evaluated the usability and impact on estimation error of standard food servings of a novel augmented reality food serving aid, ServAR. METHODS: Participants were randomised into one of three groups: 1) no information/aid (control); 2) verbal information on standard serving sizes; or 3) ServAR, an aid which overlayed virtual food servings over a plate using a tablet computer. Participants were asked to estimate the standard serving sizes of nine foods (broccoli, carrots, cauliflower, green beans, kidney beans, potato, pasta, rice, and sweetcorn) using validated food replicas. Wilcoxon signed-rank tests compared median served weights of each food to reference standard serving size weights. Percentage error was used to compare the estimation of serving size accuracy between the three groups. All participants also performed a usability test using the ServAR tool to guide the serving of one randomly selected food. RESULTS: Ninety adults (78.9% female; a mean (95%CI) age 25.8 (24.9-26.7) years; BMI 24.2 (23.2-25.2) kg/m2) completed the study. The median servings were significantly different to the reference portions for five foods in the ServAR group, compared to eight foods in the information only group and seven foods for the control group. The cumulative proportion of total estimations per group within ±10%, ±25% and ±50% of the reference portion was greater for those using ServAR (30.7, 65.2 and 90.7%; respectively), compared to the information only group (19.6, 47.4 and 77.4%) and control group (10.0, 33.7 and 68.9%). Participants generally found the ServAR tool easy to use and agreed that it showed potential to support optimal portion size selection. However, some refinements to the ServAR tool are required to improve the user experience. CONCLUSIONS: Use of the augmented reality tool improved accuracy and consistency of estimating standard serve sizes compared to the information only and control conditions. ServAR demonstrates potential as a practical tool to guide the serving of food. Further evaluation across a broad range of foods, portion sizes and settings is warranted.

Position paper on the need for portion-size education and a standardised unit of measurement.

Large portion sizes contribute to weight gain in western societies. Portion-size interventions, aids and education can be effective in helping prevent weight gain, but consumers are unsure what appropriate portions are and express confusion about existing guidelines. A lack of clarity about suggested serving size recommendations is a major barrier to food portion-size control. Therefore, standardised measurement units and unambiguous terminologies are required. This position paper summarises the evidence regarding the impact and importance of portion-size education and estimation, and outlines strategies for improving consumer understanding and application of this through the development of an international food measurement system and a range of appropriate portion control tools. In this position paper, the authors call for the standardisation of food volume measurement terminologies, units, implementation recommendations, as well as consumer education. The target audience for this paper includes nutrition and behavioural researchers, policy makers, and stakeholders who potentially influence and implement changes in national food measurement systems, which in turn impact on consumer choice.

Transfer of spatial search between environments in human adults and young children (Homo sapiens): implications for representation of local geometry by spatial systems.

Whether animals represent environmental geometry in a global and/or local way has been the subject of recent debate. We applied a transfer of search paradigm between rectangular- and kite-shaped arenas to examine the performance of human adults (using virtual environments) and children of 2.5-3.5 years (using real arenas). Adults showed robust transfer to a congruent corner in a kite-shaped arena, following training in a rectangular-shaped arena in two paradigms modeled on those used with rats and young children respectively. In contrast, the children showed no evidence of transfer of search, despite above chance performance in the rectangular arena, and above chance performance in a study where search occurred in the kite arena only. The pattern of findings suggests global aspects of environmental geometry may be used to re-establish heading, and that the matching of elements of local geometry in new global contexts may be an advanced developmental achievement.