DOI: 10.5061/dryad.83bk3j9n2
title: Baby cry recognition is independent of motherhood but improved by experience and exposure

description: Neurobiological changes affecting new mothers are known to support the
 development of the mother-infant relationship (the “maternal brain”).
 However, which aspects of parenting are actually mother-specific and which
 rely on general cognitive abilities remains debated. For example, refuting
 earlier findings, a recent study demonstrated that fathers identify their
 own baby from their cries just as well as mothers. Here we show that this
 performance is not only independent of sex, but also of parenthood status.
 We found that mothers’ ability to recognize their newborn from their cries
 increased rapidly within few days postpartum, with highly multiparous
 mothers performing better. However, both male and female nonparents could
 similarly recognize an assigned baby, even after a very short exposure. As
 in mothers, both the initial amount of experimental exposure to the baby’s
 cries (learning opportunity) and prior experience of caring for infants
 (auditory expertise) affected participants’ performance. We thus suggest
 that, rather than being female-specific or motherhood-dependent, the
 ability to recognise a baby from their cries derives from general auditory
 and learning skills. By being available to nonparents of both sexes it may
 contribute to the caregiving flexibility required for efficient
 cooperative breeding in humans.
description: Supporting dataset for Experiment 1: Individual recognition of
 newborns from their cries in postpartum mothers
 Experiment 1 aimed at evaluating postpartum mothers’ ability to
 recognize their own baby from their cries. More specifically, we tested
 whether this ability was influenced by their baby’s age at the time of
 testing, their baby’s age at the time of recording, their own age, their
 parity status, and the testing stage.
 <strong>List of variables :</strong>
 <b><i>MumID</i></b> = mother’s identity
 (included in the model as a random factor)
 <b><i>AgeMum</i></b> = participant’s age
 at the time of the experiment (in years)
 <b><i>Parity</i></b> = participant’s
 number of offspring at the time of the experiment (coded as “P1” = no
 previous offspring, “P2” = has already had 1 offspring, “P3” = has already
 had 2 or more offspring)
 <b><i>Baby</i></b> = baby’s category
 coded as “own” vs. “stranger” baby
 <b><i>AgeTest</i></b> = own baby’s age at
 the time of the experiment (in decimal hours)
 <b><i>AgeRec </i></b>= own baby’s age at
 the time of stimuli recording (in decimal hours)
 <b><i>Test </i></b>= test number coded as
 “Test1” vs. “Test2” (i.e. first versus second series of 15
 cries) <b><i>Response </i></b>=
 mothers’ answers, at whether each cry belonged to their offspring (1 =
 “yes”) or not (0 = “no”)   
 <b>Supporting dataset for </b><b>Experiment 2:
 Individual recognition of newborns from their cries in
 non-parents</b> Experiment 2 aimed at
 evaluating non-parents’ ability to recognize a given experimentally
 “assigned” baby from their cries. More specifically, we tested whether
 this ability was affected by their sex, their age, their prior experience
 at caring for babies, their current exposure to babies, and the testing
 stage. <b>List of variables
 :</b>
 <b><i>ParticipantID</i></b> = tested
 participant’s identity (included in the model as a random
 factor). <b><i>Sex</i></b> =
 participant’s sex (“female” vs. “male”),
 <b><i>Age </i></b>= participant’s age (in
 years),    
 <b><i>Experience</i></b> = participant’s
 experience at caring for baby less than 1 year old (coded as “yes” =
 already cared for babies, “no” = never cared for babies),
 <b><i>Exposure</i></b> = participant’s
 current exposure to babies aged less than 1 year old (coded as “yes” =
 have a baby in their family circle, their circle of friends or their
 neighbourhood, “no” = have not spent time with any baby
 recently), <b><i>Baby</i></b> =
 baby’s category coded as “assigned” vs. “stranger” baby,
 <b><i>BabyID</i></b> = assigned baby’s
 identity (included in the model as a random factor)
 <b><i>Test </i></b>= test number coded as
 “Test1” vs. “Test2” vs. “Test3” vs. “Test4” (i.e. first, second, third or
 fourth series of 15 cries), <b><i>Response
 </i></b>= participants’ answers, at whether each cry belonged
 to their assigned baby (1 = “yes”) or not (0 = “no”)
   <b>Supporting dataset for
 </b><b>Experiment 3: Effect of exposure on non-parents’
 ability to recognise a newborn from their cries</b> 
 Experiment 3 aimed at evaluating non-parents’ ability to
 recognize a given experimentally “assigned” baby from their cries
 depending on the quantity of input received during the training phase
 (participants’ sex, age and prior experience at caring for babies were
 balanced across training conditions). More specifically, we tested whether
 this ability was influenced by the quantity of input received during
 training (1 to 6 cries heard during training), and the testing
 stage. <b>List of variables
 :</b>
 <b><i>ParticipantID</i></b> = tested
 participant’s identity (included in the model as a random
 factor). <b><i>Baby</i></b> =
 baby’s category coded as “assigned” vs. “stranger” baby,
 <b><i>BabyID</i></b> = assigned baby’s
 identity (included in the model as a random factor)
 <b><i>Input</i></b> = participant’s input
 during the training phase (1 to 6 crying samples, taken as a continuous
 variable), <b><i>Test </i></b>=
 test number coded as “Test1” vs. “Test2” vs. “Test3” vs. “Test4” (i.e.
 first, second, third or fourth series of 15 cries),
 <b><i>Response </i></b>= participants’
 answers, at whether each cry belonged to their assigned baby (1 = “yes”)
 or not (0 = “no”)