Initially, it was believed that motor behaviour at an early age was primitive, reflex-based and monotonous. We now know that the opposite is true; foetuses from around seven weeks begin to move with some stability (Einspieler & Prechtl, 2011). Detailed studies of the motor behaviour of foetuses suggest that the movements made during this period of development are necessary for the development of skeletal, muscular and neural systems (Einspieler & Prechtl, 2011). Overall, the evidence suggests that motility from a very early age is characterised by much variation in types, amounts and quality of movement. This topic will consider typical developmental trajectories of motor development as well the consequences when motor skills are not acquired.

• Do you think this may vary from one country to another?
• Are there different opportunities for movement in some cultures than in others, e.g. living in urban or rural settings, living in a house with a garden or in a high rise apartment?

Before considering motor development, it is worth highlighting that outcome emerges from the interaction of three factors: the individual, the task and the environment (see Figure 1.).

Urie Bronfenbrenner is generally regarded as a world expert in the field of developmental psychology. His ecological systems theory suggests that development reflects the influence of five environmental systems that an individual interacts with.

• Microsystem: refers to the institutions and groups that most immediately and directly impact the child's development. For example, school and parents/carers.
• Mesosystem: refers to connections between contexts. For example, the relation of family experiences to school experiences.
• Exosystem: involves links between a social setting in which the individual does not have an active role and the individual's immediate context. For example, a husband's or child's experience at home may be influenced by a mother's experiences at work.
• Macrosystem: describes the culture in which individuals live. Cultural contexts include developing and industrialised countries, socioeconomic status, poverty, and ethnicity.
• Chronosystem: the patterning of environmental events and transitions over the life course, as well as sociohistorical circumstances.

In terms of the individual, growth is quantitative, meaning that it can be directly measured (e.g. increase in size), however, maturation is qualitative (e.g. functions of organs and tissues). They are interrelated; as the body grows, functions improve. But they are also different; as we age, growth slows, but maturation can continue throughout the lifespan. Development can be considered cephalo-caudal meaning from head to feet (consider the head size of an infant relative to their body); and proximo-distal meaning from those points close to the body’s centre to those points close to the periphery (e.g. prenatal growth; motor development).

Motor development from an early age is therefore a progression of increasingly complex motor events (milestones) through which infants achieve control over the use of their muscles for upright posture, balance, and locomotion (from holding the head erect, to rolling over, to sitting, to crawling, to standing), and manipulation of objects for interaction with the environment. By the time a child gets to around two years of age, running, climbing, jumping, balancing, catching and throwing are developed.