” […] If we assume that most consumers of information, for instance, as engineers or business and technical managers, have to find and use information within the real constraints of time to make decisions of all kinds, information overload is reduced to a matter of the management of data (facts without any interpretation), information (data interpreted meaningfully in a communicative chain of writers and readers), and knowledge (information that refers to a learning cycle) [11]. Knowledge comes in two basic forms relevant to engineering and technical communication: declarative, which addresses what, and procedural, which addresses how [12]. When it comes to decision making within the constraints of time, frustration may arise not only from information overload but also from its opposite—information underload—which occurs when there is not enough information available to make the right decision. Information overload is closely linked to high cognitive load”.
(from: Information Overload, 2012)
http://media.wiley.com/product_data/excerpt/32/11182301/1118230132-118.pdf