learning and self-identity.

Remembering intentions. Another type of activity concerns remembering prospective events in one’s life (“ prospective memory”), as opposed to the things that have happened in the past. Our everyday activities require that we constantly defer actions and plan future activities; examples include remembering to run errands, take medication, and show up for appointments.

A careful analysis of the lifelogging literature for proposed user value suggests a general focus on the processes of recollection and retrieval, but these benefits are usually implied rather than explicit.

evaluation

Do lifelogging systems deliver these benefits? One way to identify evidence of utility is through systematic evaluation (such as focused lab studies and studies of longer-term real-world use). However, such evaluations have yet to provide overwhelming evidence of effectiveness, and extended usage studies show little impact outside research labs. Worse, few lifelogging systems are in widespread use, even within the research laboratories that developed them.

In practice, total-capture systems have been used by only a small number of people (often those with direct investment in the technology), and lifelogging infrastructures11, 12 are not in widespread use. While Gordon Bell of Microsoft2 and Steve Mann of the University of Toronto18 have both “lived the vision” by recording many aspects of their everyday lives, they are unusual in the extreme extent of their engagement with lifelogging. Otherwise, there are few instances of full-fledged use of total capture.

More controlled system evaluations are also not encouraging in terms of demonstrable utility. The SenseCam (see the figure), which captures a series of still images based on movement and changes in the intensity of light and heat, has been shown to support the recollection of everyday experience, as well as retrieval of information about past events. 23 However, the same study showed that the capacity for these images to help people recollect their past experience rapidly decreased after only three months, casting doubt on whether such devices can support longer-term recollection.

Most evaluations described in the literature have examined situation-

microsoft sensecam captures a series of still images triggered by changes in activity (such as movement) and includes sensors that capture other kinds of data (such as ambient light levels and temperature); courtesy microsoft Research cambridge.

specific capture systems. For example, Filochat is an application that allows users to access spoken information from meetings via personal digital notes. Both lab experiments and a field trial at Hewlett-Packard Labs in the early 1990s demonstrated Filochat’s superiority in supporting retrieval of meeting information compared with traditional techniques (such as pen-and-paper notes and Dictaphone recordings). An active user group reported positive reactions to the system because it allowed them to generate accurate meeting minutes. Similar findings were reported in other field studies of related meeting-capture technologies; see Whittaker et al. 28 for a review. But despite such early positive results, more recent research should make us skeptical, suggesting that records may be less useful than we might first think. For example, lecture recordings don’t significantly improve student grades, 1 and evaluations of meeting-capture systems have shown little uptake of sophisticated records. 20

Other research confirms the view that digital archives may be generally less valuable than people would hope. Even when—contrary to lifelogging principles—we deliberately choose to save digital memorabilia, we seldom access them. Studies by Petrelli and Whittaker19 in 2010 of digital family memorabilia (such as photos, videos, scanned images, and email) showed that digital archives are rarely accessed. In the same study, when people with large collections of digital memorabilia were asked to select objects of mnemonic significance in their homes, less than 2% of the objects they reported were digital. 19 Other work has found that users with collections of thousands of digital photos never access the majority of them. 27

While this lack of interest in digital data doesn’t imply that all such archives have little value, it raises questions about their utility in remembering or reviewing the past. One might surmise that we simply lack effective techniques for accessing the archives. However, most situation-specific capture systems for meetings and lectures include sophisticated access tools (such as multimedia search and bespoke browsing interfaces), suggesting