Is our experience of space embodied? Do we learn that the world is three dimensional or is this something we cannot escape because of how our bodies are made? It is embodied by three lines of reasoning: (1) our bodies contain the nature of our space (2) we know space at too early an age to have learnt it from experience (3) our use of spatial metaphors imply an automatic use of our understanding of space.

Physical bodies:

Our sense of movement/acceleration of the head comes from the semi-circular channels of the ear. The three sensors are at right angles to each other like the x,y,z of a three-dimensional graph. They sense any movement as a combination of movement in three directions. That dictates 3-D space.

During embryo development, starting at (or shortly after) the single fertilized egg, development proceeds with differences between ventral and dorsal, rostral and caudial, dextral and sinistral. The chemical signals and gradients that steer development determine what will become up and down, front and back, left and right and where all the tissues will fit in that framework.

The brain, not just the human but all vertebrate brains, have a spatial centre which contains specialized neurons to represent place and space. They include place neurons, grid neurons, border neurons, heading neurons. Vision, hearing and touch cooperate in our representation of space in this internal mapping system. When we loss our place on this internal map, they feel a very particular emotion, the feeling of being lost. This system is central to episodic memory.

So given our bodies, it would be next to impossible to avoid an embodied spatial cognition.

Innate knowledge:

Now there are methods of questioning very young babies about what they know by following their gaze; they look longer at things and events they find unusual or less predictable than they do with the ordinary. This type of investigation can be done with babies that are only a few months old.

Here is part of the discussion in Spelk & Kinzler, Core knowledge (2007):

The last system (previous pages dealt with the others) of core knowledge captures the geometry of the environment: the distance, angle, and sense relations among extended surfaces in the surrounding layout. This system fails to represent non-geometric properties of the layout such as surface color or odor, and it fails under some conditions to capture geometric properties of movable objects. When young children or non-human animals are disoriented, they reorient themselves in accord with layout geometry. Children fail, in contrast, to orient themselves in accord with the geometry of an array of objects, and they fail to use the geometry of an array to locate an object when they are oriented and the array moves. Under some circumstances, children and animals who are disoriented fail to locate objects in relation to distinctive landmark objects and surfaces, such as a colored wall. When disoriented children and animals do use landmarks, their search appears to depend on two distinct processes: a reorientation process that is sensitive only to geometry and an associative process that links local regions of the layout to specific objects…This research suggests that the human mind is not a single, general-purpose device that adapts itself to whatever structures and challenges the environment affords. Humans learn some things readily, and others with greater difficulty, by exercising more specific cognitive systems with signature properties and limits. The human mind also does not appear to be a ‘massively modular’ collection of hundreds or thousands of special-purpose cognitive devices. Rather, the mind appears to be built on a small number of core systems, including the four systems just described. (object, agent and number preceded geometry/place in this description)

Here is the abstract from Regolin, Ruganil, Stancher and Vallortigara (2011) Spontaneous discrimination of possible and impossible objects (think Escher drawings) by newly hatched chicks:

Four-month-old infants can integrate local cues provided by two-dimensional pictures and interpret global inconsistencies in structural information to discriminate between possible and impossible objects. This leaves unanswered the issue of the relative contribution of maturation of biologically predisposed mechanisms and of experience with real objects, to the development of this capability. Here we show that, after exposure to objects in which junctions providing cues to global structure were occluded, day-old chicks selectively approach the two-dimensional image that depicted the possible rather than the impossible version of a three-dimensional object, after restoration of the junctions. Even more impressively, completely naive newly hatched chicks showed spontaneous preferences towards approaching two-dimensional depictions of structurally possible rather than impossible objects. These findings suggest that the vertebrate brain can be biologically predisposed towards approaching a two-dimensional image representing a view of a structurally possible three-dimensional object.

Here is the abstract from Izard, Pica, Spelke and Dehaene (2011), Flexible intuitions of Euclidean geometry in an Amazonian indegene group:

Kant argued that Euclidean geometry is synthesized on the basis of an a priori intuition of space. This proposal inspired much behavioral research probing whether spatial navigation in humans and animals conforms to the predictions of Euclidean geometry. However, Euclidean geometry also includes concepts that transcend the perceptible, such as objects that are infinitely small or infinitely large, or statements of necessity and impossibility. We tested the hypothesis that certain aspects of nonperceptible Euclidian geometry map onto intuitions of space that are present in all humans, even in the absence of formal mathematical education. Our tests probed intuitions of points, lines, and surfaces in participants from an indigene group in the Amazon, the Mundurucu, as well as adults and age-matched children controls from the United States and France and younger US children without education in geometry. The responses of Mundurucu adults and children converged with that of mathematically educated adults and children and revealed an intuitive understanding of essential properties of Euclidean geometry. For instance, on a surface described to them as perfectly planar, the Mundurucu’s estimations of the internal angles of triangles added up to ∼180 degrees, and when asked explicitly, they stated that there exists one single parallel line to any given line through a given point. These intuitions were also partially in place in the group of younger US participants. We conclude that, during childhood, humans develop geometrical intuitions that spontaneously accord with the principles of Euclidean geometry, even in the absence of training in mathematics.

Babies and some animals also can follow another’s gaze. This takes a facility with modeling 3-D space. There does not appear to be time for infants to learn about the nature of space from their own experience. A baby would need some framework in order to start learning about the world as quickly as they do.

Root of metaphor:

Finally space is at the root of a great many linguistic metaphors. We use our comfortable knowledge of space in order to understand other things by analogy. Time for instance is often expressed as a space metaphor by almost everyone no matter their language or culture.

We look forward to the future and back to the past. We go straight for the goal or we take a corner in our life. Today I am up for the challenge, tomorrow I may be down. I can rise to the top or get stuck at the bottom of the ladder. She went under under the anesthetic but he got high on the drug. Examples of spatial metaphors can go on for pages and pages but I will resist.

What ubiquitous metaphors (such as the spatial group) tell us is that we have an embodied area of cognition that is so firmly grounded and can be used to visualize, understand, express, and communicate other less grounded areas.

Even though Physics may convince us that there is actually a four dimension, or even eleven and a half, we cannot escape our experience of three dimensions. Our representation of space is embodied.