There was an Atlantic article which we received whilst studying on a Masters degree (we received it on paper, only the source is from the Internet!), aptly titled 'Is Google Making Us Stupid?' by Nicholas Carr. Since reading that article, it's been a conscious effort to avoid using search engines unless it is absolutely necessary, and the level of concentration has noticeably increased.
If anyone is interested in the article, the link is here, I shan't ask you to Google it!