proximal-distal. This principle asserts that the head
and trunk develop before the arms and legs, and the
arms and legs before the fingers and toes. Babies
learn to master control of upper arms and upper legs,
then forearms and legs, then their hands and feet,
and finally fingers and toes. An example of this is an
infant’s need to control the arm against gravity before
being able to reach for a toy.
General to Specific Principle
Lastly, the general to specific development pat-
tern is the progression from the entire use of the body
to the use of specific body parts. This pattern can be
best seen through the learned process of grasping.
Initially, infants can grossly hold a bottle with both
hands at about four months of age. After practice and
time, twelve-month-old infants can hold smaller toys
or food in each hand using a pincher grasp. This fin-
ger and thumb grasp is more precise than the grasp-
ing skill of an infant at four months. Just as the child
develops a more precise grasp with time and experi-
ence, many other motor skills are achieved simulta-
neously throughout motor development. Each
important skill mastered by an infant is considered a
motor milestone.
Motor Milestones
Motor milestones are defined as the major devel-
opmental tasks of a period that depend on movement
by the muscles. Examples of motor milestones in-
clude the first time a baby sits alone, takes a step,
holds a toy, rolls, crawls, or walks. As discussed previ-
ously, the timing of the accomplishment of each
motor milestone will vary with each child. ‘‘Motor
milestones depend on genetic factors, how the moth-
er and father progressed through their own develop-
ment, maturation of the central nervous system,
skeletal and bone growth, nutrition, environmental
space, physical health, stimulation, freedom and
mental health’’ (Freiberg 1987; Paplia and Wendko-
solds 1987). Within the motor milestones exist two
forms of motor development: gross motor develop-
ment and fine motor development. These two areas
of motor development allow an infant to progress
from being helpless and completely dependent to
being an independently mobile child.
Gross Motor Development
Gross motor development involves skills that re-
quire the coordination of the large muscle groups of
the body, such as the arms, legs, and trunk. Examples
of gross motor skills include sitting, walking, rolling,
standing, and much more (see the list of gross motor
milestones in Table 1). The infant’s gross motor activ-
ity is developed from movements that began while in
the womb and from the maturation of reflex behav-
ior. With experience, the infant slowly learns head
control, then torso or trunk control, and then is roll-
ing, sitting, and eventually walking. The first year of
a baby’s life is filled with major motor milestones that
are mastered quickly when compared to the motor
milestone achievements of the rest of the baby’s de-
velopment. In addition to the development of gross
motor skills, a baby is simultaneously learning fine
motor skills.Fine Motor Development
Fine motor development is concerned with the
coordination of the smaller muscles of the body, in-
cluding the hands and face. Examples of fine motor
skills include holding a pencil to write, buttoning a
shirt, and turning pages of a book (see the list of fine
motor milestones in Table 1). Fine motor skills use
the small muscles of both the hands and the eyes for
performance. For the first few months, babies spend
a majority of time using their eyes rather than their
hands to explore their environment. The grasping re-
flex, which is present at birth, is seen when a finger
is pressed into the baby’s palm; the baby’s fingers will
automatically curl around the person’s finger. This
grasping reflex slowly integrates and allows the devel-
opment of more mature grasping patterns. At four
months, babies will begin to more frequently reach
out for toys with their arms and hands. The reach
looks more like a swipe because the baby is learning
how to control the arm and hand. Over time, babies
learn how to make smoother and coordinated move-
ments with their arms and hands.Assessment of Gross Motor and Fine
Motor Development
Many assessment tools exist to measure a child’s
performance in regard to gross and fine motor skills.
Each assessment requires good observational skills
from the evaluator, who is typically a developmental
pediatrician, nurse, educator, occupational therapist,
or physical therapist. Some assessments call for each
item to be administered in a formal standardized
manner, so that each child is tested the same way
every time. These tests are also called normative-
based because they compare individual performance
to that of other children. Other measures encourage
professionals to ask parents questions about their
child and are based on informal observations of the
child at play. These more informal tests are referred
to as criterion-based assessments because they com-
pare individual performance to a criterion or stan-
dard. Regardless of the type of assessment, each
measure has the common purpose of evaluating the
child’s current ability to perform motor-related tasks.
Professionals use the results of these assessments to280 MOTOR DEVELOPMENT