| Sample 1 |
Mobiles: A series of 3 mobiles back and forth in front of the infant’s face (mobiles had 1, 2, and 7 colorful objects). Each mobile was moved back and forth for 20 seconds and each mobile was shown 3 times (for a total of 9 trials). Nonsense Syllables: Infants heard a female voice speaking three different syllables (ma, pa, ga) at three different increasing volumes, for a total of nine trials. Smiling Mother: Mother stood in front of her child once smiling but not talking, for one minute.
|
Episode 1: Placement of electrodes, Episode 2: Placement of a blood pressure cuff, Episode 3: Facial disapproval from an examiner or the mother, Episode 4: A noisy rotating wheel, Episode 5: Request to taste liquid from a dropper, Episode 6: Invitation to approach an unfamiliar object (a robot) or unfamiliar adults, despite a friendly invitation to do so. |
Episode 1: An unfamiliar room containing novel objects Episode 2: Application of heart rate electrodes Episode 3: Blood pressure cuff, Episode 4: Request to accept liquid through an eyedropper Episode 5: An unfamiliar woman, Episode 6: A person dressed as a clown, and Episode 7: A radio-controlled robot. (Seen at 21 months) |
| Sample 2 |
Mobiles: The visual stimuli were two sets of three mobiles differing in the number of hanging characters (1, 3, or 6 characters; 1 set of brightly colored Winnie the Pooh and a 2nd set of Mickey Mouse mobiles) that were displayed at the infant’s eye level, 12 inches from the face for nine trials of 20 sec each, with an interstimulus interval of 10 sec Nonsense Syllables: The first set of auditory stimuli were a set of taped nonsense syllables (ma, ga, pa) presented in three consecutive 10-s trials, with 5-s interstimulus intervals. The second set of auditory stimuli was sentences (8 short sentences, 6 s in duration, followed by a 2-s interstimulus interval) presented in pairs. The pairs differed in the number of voices speaking and, as a result, the volume of the presentation.
|
Episode 1: 5 minutes of free play Episode 2: Stranger play with truck (1 min quiet play before invite, 2–3 minutes total) Episode 3: Stranger brings in robot (2 minutes) |
Episode 1: 5 minutes of free play Episode 2: Stranger play with truck (1 min quiet play before invite, 2–3 minutes total) Episode 3: Stranger brings in robot (2 minutes) Episode 4: Reaction to stranger dressed in clown costume Episode 5: Willingness to climb through inflatable tunnel. (Seen at 24 months) |
| Sample 3 |
Mobiles: The visual stimuli were two sets of three mobiles differing in the number of hanging characters (1, 3, or 6 characters; 1 set of brightly colored Winnie the Pooh and a 2nd set of Mickey Mouse mobiles) that were displayed at the infant’s eye level, 12 inches from the face for nine trials of 20 sec each, with an interstimulus interval of 10 sec Nonsense Syllables: The first set of auditory stimuli were a set of taped nonsense syllables (ma, ga, pa) presented in three consecutive 10-s trials, with 5-s interstimulus intervals. The second set of auditory stimuli was sentences (8 short sentences, 6 s in duration, followed by a 2-s interstimulus interval) presented in pairs. The pairs differed in the number of voices speaking and, as a result, the volume of the presentation.
|
N/A |
Episode 1: 5 minutes of free play Episode 2: Stranger play with truck (1 min quiet play before invite-2–3 minutes total) Episode 3: Stranger brings in robot (2 minutes) Episode 4: Reaction to stranger dressed in clown costume Episode 5: Willingness to climb through inflatable tunnel. (Seen at 24 months) |
