Researchers at Columbia University have found that increasing number of users relied on their computers as a form of "external memory" as frequent use of online information libraries "wired" human brains.
The study, examining the so-called "Google effect", found people had poor recall of knowledge if they knew where answers to questions were easily found, `The Daily Telegraph` newspaper reported.
The researchers found that people were increasingly bypassing discussions with friends to use the Internet as their main source of information.
Prof Betsy Sparrow, who led the study, said such web tools were making information easy to forget and that if people could not find answers immediately it could feel like "going through withdrawal".
"We are becoming symbiotic with our computer tools, growing into interconnected systems," said Prof Sparrow, from Columbia`s psychology department.
"We have become dependent on them to the same degree we are on all the knowledge we gain from our friends and coworkers - and lose if they are out of touch. Human memory is adapting to new communications technology.
"We`re not thoughtless empty-headed people who don`t have memories anymore. But we are becoming particularly adept at remembering where to go find things. And that`s kind of amazing," she added.
In the study, the researchers undertook four experiments involving student volunteers. They firstly asked 46 students from the Harvard, the Ivy League university, a series of true-false questions based on trivia such as, "An ostrich`s eye is bigger than its brain" before showing them words in different colours.
When the words could be linked to Internet, students responded more slowly and admitted they were contemplating
searching for the answers on the web. Another 60 students were then given 40 statements to type on a computer before being told that the information would either be saved or erased.
They discovered that people who believed the data would be saved were less likely to remember.
Another experiment involved 28 undergraduates from Columbia who were asked trivia questions. They were allowed to
take notes and the researchers found they too struggled to remember information that would be saved.
Finally, a further 34 Columbia students remembered where they stored their information in folders on their computers better than they were able to recall the information itself.
Prof Sparrow admitted it remained unclear what the effects of being so "wired" will be on people over the coming years. She said the Internet had replaced a person`s circle of friends where people would traditionally look for information.
"(They) did not make the effort to remember when they thought they could later look up the trivia statement they had
read. It may be no more than nostalgia at this point, however, to wish we were less dependent on our gadgets.
"(It shows) we must remain plugged in to know what Google knows," she added.