Baby Alexa's brother Fred has started screaming whenever he is left in his room for a nap. The first few times this woke up from her own nap, but now she sleeps right through it.
Fred always jumps off his bed after his nap with a loud bang. He then runs downstairs and greets Alexa with a tickle, making her laugh and cough reflexively. Soon, Alexa begins to laugh and cough when she hears the bang, before seeing her brother.
Alexa lies in her crib while her father shows her a ladybug toy. Every 10 seconds or so he takes the toy away for a few seconds, and then puts it over her head again. Each time, Alexa looks again at the ladybug. About the 10th time, her father drops the ladybug by mistake and the dog runs off with it but Alexa continues to look for the toy to appear
Operant (Instrumental) Conditioning
Alexa randomly makes many vocalizations throughout the day. Her "coos" elicit laughter and hugging from her parents, and this seems to make her cooing more frequent.
When Alexa sees her big brother Fred banging on a drum, she starts beating her hand on the tray of her highchair (as if it is a drum)
Alexa's family has lots of photos on the wall, and one of these is of Alexa's mom and aunt, who look a lot alike. When Alexa is 3 months old, she looks equally long at the two women in the photo, but by 6 months of age, Alexa spends more time looking at her mother's face in the photo than that of her aunt