1. Reading 1:

2. Direct Perception X-Y eye experiment The spinning wheel, others – Is perception direct?

3. Air and Ground Theory Air – items in the air in a st. line project onto the same part of the retina Ground – texture gradients, occlusion and so on come into play. – Veridical perception

4. Optic Flow Invariant structures Time to contact – τ (tau) – Inverse of relative rate of expansion of image on retina – Order/control parameters?

5. Affordances

6. Warren – pi values – Ratios of leg length to stair height – Ratios of aperture width to shoulder width – Order/control parameters?

7. Reading 2

8. Change/development Gradual? Variable/discontinuous/regressions/progressions

9. Constraints Newell: Organismic, Task, Environmental Schmidt & Fitzpatrick: CNS, Action System, Environment Walking/Crawling: preferred activity depended on current movement repertoire. Order/control parameters?

10. Stepping 8 weeks: Kick = step 8 weeks: water = step – Leg mass: muscle vs. fat in first two months – Order/control parameters?

11. Reaching/Grasping Vertical (less against gravity): – 12-19 wks showed mature (ish) reaching/grasping Recline/supine (more against gravity): – 12-19 wks poorer coordination and less frequent movements Overall model: reaching/grasping affected by: body orientation, arm weight, arm circumference. – Order/control parameters?

12. Spontaneous arm movements Arm movements depended on posture and girth of arm

13. Visual Information as a constraint Attunement – Information used changes as person matures – Implies change in perceptual circuitry with change in motor capability Binocularity and stereopsis – Use of binocular cues increases with age – Order/control parameters?