source: Historically, the sensations of itch and pain have not been considered to be independent of each other until recently, where it was found that itch has several features in common with pain, but exhibits notable differences.
target: Historically, the sensations of itch and pain have not been considered to be independent of each other until recently. It was found that itch has several features in common with pain, but exhibits notable differences.
references: Historically, the sensations of itch and pain have not been considered to be independent of each other until recently. It was found that itch has several features in common with pain, but exhibits notable differences. People used to think that itch and pain were completely related, but now we know that is not true. Itch and pain haven't been thought about as separate from each other until not too long ago. Usually, the feelings of itch and pain have not been considered to be independent of each other until recently. Traditionally, itch and pain have not been considered as separate from each other.  Recently, however, it was found that itch has some similarities to pain, but also has a lot of differences. Historically, itching and pain haven't be considered independent of each other until recently. It was found itch has some features in common with pain, but has differences as well. Historically, the sensations of itch and pain weren't considered to be independent of each other until recently, where it was found that they are similar but different. Itch and pain have common features. Historically, itch and pain were not considered independent of each other. Recently, it was found that itch has some notable differences from pain with several features in common. Based on history, the feelings of itch and pain have not been considered to be separated of each other. But recently,  people found out that itch has several things in common with pain, but itch shows more obvious differences.