Studies have shown that such disconnectedness leads not only to anxiety, depression, and underachievement but also to substance abuse, disruptive behavior, and a host of medical problems in both children and adults.

NPR: Excerpt: 'Delivered from Distraction'

The children in the two groups showed very little to no significant differences in terms of emotional health, behavior or sleep problems.

CNN: Should babies be allowed to 'cry it out'?