- Young babies laugh during both inhalation and exhalation,
similar to chimps but this changes as the baby develops to resemble adult
human laughter which occurs mainly during exhalation
- Analyzing the laughter pattern and other non-verbal
forms of showing emotion may help identify babies at risk of developmental
Young babies at two to three months of
age laugh in a manner identical to non-human primates such as chimps.
However, this alters as the baby develops to resemble adult
human laughter, reveals a recent study.
The findings of the study may have application in determining babies at risk of
Disa Sauter, a psychologist and associate
professor at the University of Amsterdam in the Netherlands, during a
discussion at the Acoustical Society of America's 176th Meeting, organized in
conjunction with the Canadian Acoustical Association's 2018 Acoustics Week in
Canada presented the findings of the study.
do Babies Laugh?
- Sauter and her colleagues studied laughter clips of 44
infants and children between 3 and 18 months of age. The recordings were
obtained from online videos captured while the babies were interacting
- The recordings were analyzed by 102 listeners, drawn
from across psychology students, who determined the degree to which the
laughter in each clip was produced during inhalation versus exhalation
- The study found that the youngest babies at around
three months of age laughed during both inhalation and exhalation, similar
to non-human primates such as chimps. However, older babies laughed predominantly during exhalation similar
to older children and adults
It is unclear why only humans among
primates laugh during exhalation but it may be due to the voice control they
develop with speech. The shift in pattern of laughter is gradual and not
associated with any specific developmental milestones. Also the current
laughter pattern analysis was performed by non-expert listeners
‘Young babies laugh during both inhalation and exhalation, which is remarkably identical to how non-human primates such as chimps laugh.’
Sauter said, "Adult humans sometimes laugh on the inhale
but the proportion is markedly different from that of infants' and chimps'
laughs. We are currently checking these results against judgments by
phoneticians, who are making detailed annotations of the laughter."
- The team is also examining if there is a link between
the proportion of laughter produced during inhalation and exhalation and
the reasons why people laugh, which also change with age.
Typically, infants and younger babies
laugh as the result of physical interaction like tickling
. However, in
older individuals, laughter occurs both due to physical play and social
Developmental disorders, such as autism spectrum
and intellectual disabilities
usually begin during
childhood, but persist into adulthood. They can affect learning, speech development and other milestones, social
interactions with others, ability to understand and think independently and can
prevent children from achieving their full potential.
The reasons for
developmental disorders are unclear, but
it is important to recognize these early so that intervention measures can be
started sooner with better outcomes in the long-term
Dr.Sauter in conclusion said, "I'd be interested in
seeing whether our findings apply to other vocalizations than laughter.
Ultimately, the research could offer insight into vocal production of children
with developmental disorders."
If it is known how
normally developing babies sound like, it would
be interesting to study infants at risk of
development disorders to find out if there are any early signs of
atypical development in their nonverbal vocalizations of emotion.
- Acoustical Society of America - (https://acousticalsociety.org/)
- Human babies laugh like chimpanzees - (https://tech2.org/human-babies-laugh-like-chimpanzees/)
- Early child development - Disabilities and developmental disorders - (http://www.who.int/topics/early-child-development/disability-developmental-delay/en/)