Models of the AT
Motor changes from the AT
Several experiments suggest that the AT affects postural systems. AT teachers 1 , AT lessons 1 and AT-like instructions 2 affect postural tone to reduce stiffness by making the postural support more dynamically responsive. The AT also affects movement 3-7 as well as balance 8,9 , but these changes may result indirectly from postural changes 5 , rather than learning to move or balance in a specific way. Neurological Models of AT Postural Change. So we know the AT affects postural support and this may explain other motor effects. The next question is how, neurologically speaking, does the AT affect the postural system? The answer is that we don’t know yet but there are several possibilities, some or all of which may be true.
1) Low-level posture-specific. The AT may be changing lower level parameters postural-system feedback thresholds and gains. These would be slow to change and persistent. An example might be how a lumber curve changes gradually over time.
2) High-level posture-specific. The AT may be specifying higher-level postural system behaviour. This would be more adaptable and more likely to be implemented more transiently “in the moment”. This could be for instance attending to a body region to engage it or sensitise its reactions, or could be at a more strategic level, for instance determining the configuration or “chunking” of what body parts are stabilised together to form a unit.
3) General. One possibility is that AT affects posture via a general neural subsystem that relates to but is not specific to posture. One such possibility is the brain’s representation of the body in space. Thus, the AT’s postural activities may be acting to enhance or calibrate the body scheme.
4) Constraints. The AT may affect postural behaviour though constraints that specify aspects of behaviour, for example constraining the neck muscles to not tense when going to move. A recent AT-inspired study found that this specific constraint on neck muscles has general motor effects, presumably though biomechanical spreading through the kinetic chain 10 . Although constraints may form an important part of AT learning, they do not shed light on the AT’s persistent postural effects 1 .
Psychophysical changes are central to the AT, however to date no studies have revealed how the AT affects cognitive, psychological or emotional phenomena. Despite this, the interplay between such cognitive factors and motor behaviour is currently a hot topic on the frontiers of neuroscience. While not AT-specific, changes in posture have been found to affect psycho-cognitive state (refs), in particular, poor neck posture is correlated with specific of cognitive processes 11 . Psychophysical models of the AT will be developed as more data becomes available.