We're used to thinking about emotions as being very different from logic. In fact, they are often closely connected. When a baby is learning, she is generally attentive, involved and happy. Emotions are the fuel that power children's exploring and learning. Children pay attention to new things and therefore learn from them, because they evoke positive or negative emotions. As we grow older, we learn to make ourselves pay attention to certain things because we know we have to, but we never learn them as well as when we are emotionally involved.
With my baby, a good sign is that she is learning is that she is laughing, smiling and cooing, or simply looking with a very intent gaze. Rocking, holding, tickling, singing and talking feeds emotional growth and at the same time strengthens desire and ability to learn.