31.1 Introduction: Infant, Child, and Adolescent Development
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Table 31.1-3
Language Development
Age and Stage of
Development
Mastery of Comprehension
Mastery of Expression
0–6 mos
Shows startle response to loud or sudden sounds;
Attempts to localize sounds, turning eyes or head;
Appears to listen to speakers, may respond with
smile; Recognizes warning, angry, and friendly
voices; Responds to hearing own name
Has vocalizations other than crying; Has differential
cries for hunger, pain; Makes vocalizations to show
pleasure; Plays at making sounds Babbles (a repeated
series of sounds)
7–11 mos
Attending-to-
Language
Shows listening selectivity (voluntary control over
responses to sounds); Listens to music or singing
with interest; Recognizes “no,” “hot,” own name;
Looks at pictures being named for up to 1 minute;
Listens to speech without being distracted by other
sounds
Responds to own name with vocalizations; Imitates the
melody of utterances; Uses jargon (own language);
Has gestures (shakes head for no); Has exclamation
(“oh-oh”); Plays language games (pat-a-cake,
peekaboo)
12–18 mos
Single-Word
Shows gross discriminations between dissimilar
sounds (bells vs. dog vs. horn vs. mother’s or
father’s voice); Understands basic body parts, names
of common objects; Acquires understanding of some
new words each week; Can identify simple objects
(baby, ball, etc.) from a group of objects or pictures;
Understands up to 150 words by age 18 mos
Uses single words (mean age of first word is 11 months;
by age 18 months, child is using up to 20 words);
“Talks” to toys, self, or others using long patterns of
jargon and occasional words; Approximately 25%
of utterances are intelligible; All vowels articulated
correctly; Initial and final consonants often omitted
12–24 mos
Two-Word
Messages
Responds to simple directions (“Give me the ball”)
Responds to action commands (“Come here,” “Sit
down”)
Understands pronouns (me, him, her, you)
Begins to understand complex sentences (“When we
go to the store, I’ll buy you some candy”)
Uses two-word utterances (“Mommy sock,” “all gone,”
“ball here”); Imitates environmental sounds in
play (“moo,” “mmm, mmm,” etc.); Refers to self by
name, begins to use pronouns; Echoes two or more
last words of sentences; Begins to use three-word
telegraphic utterances (“all gone ball,” “me go now”);
Utterances 26% to 50% intelligible; Uses language to
ask for needs
24–36 mos
Grammar
Formation
Understands small body parts (elbow, chin, eyebrow);
Understands family name categories (grandma,
baby)
Understands size (little one, big one)
Understands most adjectives
Understands functions (why do we eat, why do we
sleep)
Uses real sentences with grammatical function words
(can, will, the, a); Usually announces intentions
before acting “Conversations” with other children,
usually just monologues Jargon and echolalia
gradually drop from speech Increased vocabulary
(up to 270 words at 2 years, 895 words at 3 years);
Speech 50% to 80% intelligible P, b, m articulated
correctly; Speech may show rhythmic disturbances
36–54 mos
Grammar
Development
Understands prepositions (under, behind, between)
Understands many words (up to 3,500 at 3 yrs, 5,500
at 4 yrs)
Understands cause and effect (What do you do when
you’re hungry? cold?)
Understands analogies (Food is to eat, milk is to ____
Correct articulation of
n, w,
ng,
h,
t, d,
k,
g
; Uses
language to relate incidents from the past; Uses wide
range of grammatical forms: plurals, past tense,
negatives, questions; Plays with language: rhymes,
exaggerates; Speech 90% intelligible, occasional
errors in the ordering of sounds within words; Able
to define words; Egocentric use of language rare;
Can repeat a 12-syllable sentence correctly; Some
grammatical errors still occur
55 mos on True
Communication
Understands concepts of number, speed, time, space;
Understands left and right; Understands abstract
terms; Is able to categorize items into semantic
classes
Uses language to tell stories, share ideas, and discuss
alternatives; Increasing use of varied grammar;
spontaneous self-correction of grammatical errors;
Stabilizing of articulation f, v, s, z, l, r, th, and
consonant clusters; Speech 100% intelligible
(Reprinted from Rutter M, Hersov L, eds.
Child and Adolescent Psychiatry
. London: Blackwell; 1985, with permission.)
emotional life. The smiling response occurs in two phases: the
first phase is endogenous smiling, which occurs spontaneously
within the first 2 months and is unrelated to external stimula-
tion; the second phase is exogenous smiling, which is stimu-
lated from the outside, usually by the mother, and occurs by
the 16
th
week.
The stages of emotional development parallel those of cog-
nitive development. Indeed, the caregiving person provides
the major stimulus for both aspects of mental growth. Human
infants depend totally on adults for survival. Through warm and
predictable interactions, an infant’s social and emotional reper-
toire expands with the interplay of caregivers’ social responses
(Table 31.1-5).
In the first year, infants’ moods are highly variable and inti-
mately related to internal states such as hunger. Toward the sec-
ond two thirds of the first year, infants’moods grow increasingly
related to external social cues; a parent can get even a hungry
infant to smile. When the infant is internally comfortable, a
sense of interest and pleasure in the world and in its primary
caregivers should prevail. Prolonged separation from the mother
