the design of many lifelogging user interfaces) that place, events, and people
are stronger cues than time. 5 Other research has found that cues can trigger
inferences about what must have happened in someone’s life, rather than
genuine recollection23; for example, a
photo showing us having lunch with
friends may cause us to truly remember
the event or simply lead us to conclude
we must have been there. Finally, while
recollecting the past is highly dependent on the kind of cues presented to
people, for prospective memory (
memory for future events and intentions),
the important issue is not so much
the type of cue but rather when a cue
is delivered, allowing an intention to
be remembered at the right time and
place. 24 This observation suggests that
the capture of data (such as location or
other contextual cues) might be used to
trigger reminders rather than provide
content to be remembered.
These observations run counter to
much of the rhetoric surrounding lifelogging, where such phrases as “digital
memories” and “experience capture”
are often used. They show instead the
importance of understanding the precise relationship between the cues we
are able to capture through lifelogging
technologies and the memory experiences they trigger, with clear implications for how we might design improved systems.
Support for the Five Rs. Most lifelogging proponents presume that the systems deliver benefits without being
specific about what the benefits might
be, assuming a one-system-suits-all
approach. As we outlined earlier in
the section on lifelogging benefits, the
psychological literature distinguishes
many different types of memory, each
involving different retrieval processes.
Thus, it is not simply a question of what
the system captures but determining
how such a system would be used. This
determination depends largely on the
type of memory being targeted or, more
generally, the kind of benefit system designers hope to deliver to end users.
Many total-capture systems implicitly seem to address recollection, or remembering past personal experiences.
It is well known in the psychological
literature that there are strong connections between these autobiographical
memories and visual images. 8 This
systems supporting
reminiscence and
reflection have
received far less
attention than
those supporting
recollection and
retrieval.
suggests that the interfaces for such
systems should focus on images as the
backbone of their design. In contrast,
systems for retrieval need not be concerned with recollection, but rather
with efficient ways of searching though
large heterogeneous collections of data
and so provide access to metadata that
might support effective search. If system designers decide to support
reminiscence, other kinds of factors become
important (such as optimizing the sharing of data with others). Systems for
reflection might be different still where
abstraction is important, offering flexible and novel methods for viewing personal data in ways that might surprise,
provoke, or educate users. Finally, designing systems to support remembering
intentions need to focus on delivering
timely cues in appropriate contexts if
they are to provide effective reminders.
Applying such memory taxonomies
is vital for designing effective systems.
First, they clarify the aspects of memory the systems are trying to support;
without such clarification it is difficult
to know whether the systems succeed.
Second, understanding the relevant
psychological processes allows designers to create systems to better support
the processes. Third, taxonomies can
suggest new directions for exploration;
for example, systems supporting reminiscence and reflection have received
far less attention than those supporting recollection and retrieval.
Offloading and metamemory. Much
of the lifelogging approach is motivated by the observation that human
memory is fallible. Lifelog proponents
argue we need to remove the memory
burden from humans, offloading it to
reliable and comprehensive external
digital stores. These claims need careful scrutiny, as we calculate the costs
associated with digital archives, even
if they make it possible to store vast
amounts of data. For example, the effort required to capture, create, and
maintain some kinds of data can be
prohibitive. Moreover, accessing data
can be inefficient compared with exploiting “organic” human memory.
How, when, and why people exploit external memory tools has been
studied extensively in the psychological subfield of metamemory, 6 which
addresses people’s understanding of
the strengths and weaknesses of their