Poster #160 - Falling Like a Baby: High Frequency, Low Severity, & Little Evidence of Deterrence

• In Event: 1-061 - Poster Session 02
  In Poster Session: PS 02 Section - Perceptual, Sensory, Motor

Integrative Statement

Infants fall a lot. We observed the frequency and severity of 1623 falls during ~20 minutes of free play in 290 toddlers varying in age (11.8 to 20.0 months) and walking experience (2 days to 10.3 months). The number of falls/hour in motion (M=39.0) was negatively correlated with walking experience, r(259)=-.30, p<.001, and age, r(262)=-.27, p<.001, but remained high even for experienced walkers (Figure 1A).
Infants fall frequently in a wide variety of contexts—in different play environments and during different activities (Figure 1B). Despite a high frequency of falls, we found little evidence that impacts were serious. After floor falls, caregivers rarely showed concern (4.8% of falls), infants rarely cried (2.4% of falls), and infants recovered from falling and returned to play within M=2.6 seconds.
Why were infants’ falls so trivial? Infants mitigated impact forces—and therefore, the severity of falls—by taking reactive steps, lowering their center of mass, catching themselves with their hands, and distributing forces across body parts. After losing balance, infants took 1-3 quick, reactive steps in 71.1% of falls. Infants are short and close to ground (M height=78.8 cm), and in 79.6% of falls, infants bent their knees prior to impact, which further lowered their center of mass. They outstretched their hands within M=94.4 milliseconds to break a fall.
Overall, forward falls were more frequent (63%) than backward (27%) and sideway falls (10%) (Figure 2B). Most falls (78.2%) involved multiple body segments in a sequence of impacts that distributed potentially injurious forces (e.g., falling first onto hands, then legs), occasionally in a long string (e.g., legs, hands, arms, torso, head). For the 21.8% of falls that involved only a single body impact, most were onto the hands (15.9% out of 21.8%), and the remainder were onto the buttocks (2.5% out of 21.8%) and legs (2.4% out of 21.8%). Head (3.9% of all falls) and trunk (9.2% of all falls) impacts were rare, and always occurred after first falling onto a more padded body part.
Falling has neither short-term nor long-term deterrence effects on infant’s walking. Infants were not deterred from walking after repeated falls in free play. Infants took the same number of steps in the 2 minutes before a fall (M=109.26) as after a fall (M=106.16), t(584)=1.33, p=.18). Similarly, infants spent the same amount of time in motion before a fall (M=48.03) as after a fall (M=46.49), t(584)=1.53, p=.12). A prior history of serious falls was also not a deterrent. Infants with prior history of serious falls took more steps per hour (M=4021.7) and spent more time in motion (M=28.0 minutes/hour) compared with infants with no history of serious falls (M=3190.4 steps/hour and M=23.1 minutes/hour); ts(157)>55.44, ps<.001.
We conclude that infant falls are frequent but trivial, and are not salient sources for learning. We hypothesize that skills requiring vast amounts of experience, such as walking, incur a low penalty for errors and therefore infants are not deterred from practicing to the point of mastery.

Authors

• Danyang Han, New York University
  Presenting Author

• Hannah Borenstein, New York University
  Non-Presenting Author

• Shohan Hasan, New York University
  Non-Presenting Author

• Catherine S. Tamis-LeMonda, New York University
  Non-Presenting Author

• Karen E Adolph, New York University
  Non-Presenting Author