User:Marco Chemello (WMIT)/sandbox12

Navigation
Navigation is the ability of animals including humans to locate, track, and follow paths to arrive at a desired destination.

Navigation requires information about the environment to be acquired from the body and landmarks of the environment as frames of reference to create a mental representation of the environment, forming a cognitive map. Humans navigate by transitioning between different spaces and coordinating both egocentric and allocentric frames of reference.

Navigation has two major components: locomotion and wayfinding. Locomotion is the process of movement from one place to another, in animals including humans. Locomotion helps you understand an environment by moving through a space in order to create a mental representation of it. Wayfinding is defined as an active process of following or deciding upon a path between one place to another through mental representations. It involves processes such as representation, planning and decision which help to avoid obstacles, to stay on course or to regulate pace when approaching particular objects.

Navigation and wayfinding can be approached in the environmental space. According to Dan Montello's space classification, there are four levels of space with the third being environmental. The environmental space represents a very large space, like a city, and can only be fully explored through movement since all objects and space are not directly visible. Also Barbara Tversky systematized the space, but this time taking into consideration the three dimensions that correspond to the axes of the human body and its extensions: above/below, front/back and left/right. Tversky ultimately proposed a fourfold classification of navigable space: space of the body, space around the body, space of navigation and space of graphics.

Human navigation
In human navigation people visualize different routes in their minds to plan how to get from one place to another. The things which they rely on to plan these routes vary from person to person and are the basis of differing navigational strategies.

Some people use measures of distance and absolute directional terms (north, south, east, and west) in order to visualize the best pathway from point to point. The use of these more general, external cues as directions is considered part of an allocentric navigation strategy. Allocentric navigation is typically seen in males and is beneficial primarily in large and/or unfamiliar environments. This likely has some basis in evolution when males would have to navigate through large and unfamiliar environments while hunting. The use of allocentric strategies when navigating primarily activates the hippocampus and parahippocampus in the brain. This navigation strategy relies more on a mental, spatial map than visible cues, giving it an advantage in unknown areas but a flexibility to be used in smaller environments as well. The fact that it is mainly males that favor this strategy is likely related to the generalization that males are better navigators than females as it is better able to be applied in a greater variety of settings.

Egocentric navigation relies on more local landmarks and personal directions (left/right) to navigate and visualize a pathway. This reliance on more local and well-known stimuli for finding their way makes it difficult to apply in new locations, but is instead most effective in smaller, familiar environments. Evolutionarily, egocentric navigation likely comes from our ancestors who would forage for their food and need to be able to return to the same places daily to find edible plants. This foraging usually occurred in relatively nearby areas and was most commonly done by the females in hunter-gatherer societies. Females, today, are typically better at knowing where various landmarks are and often rely on them when giving directions. Egocentric navigation causes high levels of activation in the right parietal lobe and prefrontal regions of the brain that are involved in visuospatial processing.

Franz and Mallot proposed a navigation hierarchy in Robotics and Autonomous Systems 30 (2006):

Wayfinding taxonomy
There are two types of human wayfinding: aided and unaided. Aided wayfinding requires a person to use various types of media, such as maps, GPS, directional signage, etc., in their navigation process which generally involves low spatial reasoning and is less cognitively demanding.

Unaided wayfinding involves no such devices for the person who is navigating. Unaided wayfinding can be subdivided into a taxonomy of tasks depending on whether it is undirected or directed, which basically makes the distinction of whether there is a precise destination or not: undirected wayfinding means that a person is simply exploring an environment for pleasure without any set destination.

Directed wayfinding, instead, can be further subdivided into search vs. target approximation. Search means that a person does not know where the destination is located and must find it either in an unfamiliar environment, which is labeled as an uninformed search, or in a familiar environment, labeled as an informed search.

In target approximation, on the other hand, the location of the destination is known to the navigator but a further distinction is made based on whether the navigator knows how to arrive or not to the destination. Path following means that the environment, the path, and the destination are all known which means that the navigator simply follows the path they already know and arrive at the destination without much thought. For example, when you are in your city and walking on the same path as you normally take from your house to your job or university.

However, path finding means that the navigator knows where the destination is but does not know the route they have to take to arrive at the destination: you know where a specific store is but you do not know how to arrive there or what path to take. If the navigator does not know the environment, it is called path search which means that only the destination is known while neither the path nor the environment is: you are in a new city and need to arrive at the train station but do not know how to get there.

Path planning, on the other hand, means that the navigator knows both where the destination is and is familiar with the environment so they only need to plan the route or path that they should take to arrive at their target. For example, if you are in your city and need to get to a specific store that you know the destination of but do not know the specific path you need to take to get there.

Individual differences in navigation and wayfinding
Navigation and wayfinding may differ between people by gender, age, and other attributes. In the spatial cognition domain, such factors can be:


 * Visuospatial abilities. i.e. the generation, retaining, and transformation of abstract visual images. Visuospatial abilities can be distinguished in sub-factors as spatial perception, spatial visualisation, and mental rotation and measured with specific tasks.
 * Spatial-related inclinations: i.e., the preferences self-reported (using questionnaires) related to spatial and environment information and settings such as spatial anxiety, sense of direction (personal evaluation of one’s ability to orient and locate oneself within an environment), survey and route preference (also called orientation and route strategies; people’s preferred way to represent the environment in map-like or person point of view, pleasure of exploring (individuals who enjoy exploration) and spatial self-efficacy (the belief to be able to accomplish a spatial task).

Evidence
Experimental, correlational and case study approaches are used to find patterns in individual differences. Correlations approach is based on a modality to understand individual differences in navigation and wayfinding abilities to compare groups or examining the relation between variables at the continuous level. Experimental approach examines the causality of the relationship between variables. It manipulates one variable (independent variable) and investigates the impact on environment recall (dependent variable). Case studies approach is used to understand to what extent a particular profile is related to spatial representation and associated features such as, cases of brain lesions or degenerative diseases (involving brain structures and network of cognitive map) or cases of cognitive and behavioural difficulties in acquiring environment information in absence of brain deficits (as in the case of developmental topographical disorientation).

Gender differences
Gender is a source of individual differences in navigation and wayfinding. Men show more confidence during navigation in comparison to women and in the final environment representation accuracy even the gender difference can be attenuated by some factors (as outcome variables, feedback, familiarity).

Females experience higher levels of spatial anxiety than men. Further two different wayfinding strategies are used by men and women: women prefer to use route strategy more, whilst men use survey (orientation) strategy more. Route strategy is related to following directional instructions, whilst survey (orientation) strategy is the use of references in the environment in relation to their position.

Examining relations at the continuous level, gender is a predictor that can influence navigation success - both males and females can perform successfully. However, the ability to form mental representations of new environments after navigation is impacted by different patterns of relations involving strategy, beliefs/self-efficacy and visuospatial cognitive abilities. Therefore, both males and females involve the use of visuospatial individual factors, abilities and inclinations, that with different patterns of relations influence navigation and wayfinding performance.

Age differences
The ability to learn the environment and navigate increases with age. Age group comparison studies show that children become able earlier to acquire and to manage egocentric knowledge (as to repeat a path) and later (at least most of evidence) show allocentric knowledge (as expressed by finding shortest paths) even these abilities can be subject to individual differences also in children. In older adults abilities in spatial domain decrease showing a decrease of spatial learning and representation abilities, even the differences between young and older adults are related to type of tasks. In fact older adults are more sensible to decline in allocentric knowledge with respect to the younger ones. Visuo-spatial abilities (as visuospatial working memory and rotation) decline in ageing and attitudes tend to be maintained quite stable; both abilities and attitudes, however, in different extent contribute to maintain the spatial learning and navigation accuracy in elderly.