1) Identify typical development associated with any given age across each developmental domain: gross motor, fine motor, oromotor/language, socioemotional/cognitive
2) Integrate the progressions of development with the underlying changes in the nervous system
3) Explore the influences of environment and experience on development
For any therapist, it is an expectation that they understand typical sensorimotor development to effectively identify atypical development and to understand some of the movement patterns demonstrated by patients with neurologic disorders. This chapter will introduce the reader to typical sensorimotor development in relation to the maturation of the nervous system, beginning during the fetal period and extending through adolescence, when mature movement patterns have been achieved. Although physical therapists aren’t typically responsible for evaluating fine motor skills, and language, social, or cognitive skills, typical development in each of these areas is described to afford the practitioner with the knowledge to develop suitable activities for therapy as well as to provide a basis for subsequent referral to appropriate practitioners, when a delay is suspected. However, it should always be kept in mind that children develop at different rates, depending on environment, experience, maturation, and personality, so ages of behavior are averages with some children acquiring certain skills earlier or later than others.
Development can be divided into five domains: (1) gross motor – large muscle movements; (2) fine motor – small dexterous movements of the hand that support activities of daily living; (3) language – the acquisition of verbal and nonverbal expressive and receptive communication skills; (4) cognitive – the ability to reason, problem-solve, and remember; and (5) socioemotional/behavioral – the development of attachment to others, the ability to regulate behavior (self-regulation), and to interact in many environments with others.1 For the discussion of early development, we have added oromotor development to language, as the two are related and eating is critical for adequate nutrition and overall development. We will also include some discussion of maturation of the special senses in the infant.
While the development of the neural tube and the nervous system are described in detail in Chapter 19 in relation to neural tube disorders, and developmental neuroplasticity is described in more detail in Chapter 9, we will just introduce some general concepts as they relate to behavioral development in this chapter. Brain development occurs as a process of neural and glial cell proliferation, migration of these cells to the appropriate target region, axonal growth, and synapse proliferation, followed by pruning of synapses, based on usage with those underutilized dying and those utilized most strengthening their connections. Our discussion of behavioral development will include the underlying neurologic changes, supporting these behaviors.
Fetal movements are first noticeable via ultrasound imaging about week 7 of gestational age (GA); these early movements are so ...