A plethora of sensors embedded in wearable, mobile, and infrastructure devices allow us to seamlessly capture large parts of our daily activities and experiences. It is not hard to imagine that such data could be used to support human memory in the form of automatically generated memory cues, e.g., images, that help us remember past events. Such a vision of pervasive "memory-augmentation systems", however, comes with significant privacy and security implications, chief among them the threat of memory manipulation: without strong guarantees about the provenance of captured data, attackers would be able to manipulate our memories by deliberately injecting, removing, or modifying captured data. This work introduces this novel threat of human memory manipulation in memory augmentation systems. We then present a practical approach that addresses key memory manipulation threats by securing the captured memory streams. Finally we report evaluation results on a prototypical secure camera platform that we built.

Today's sensor-rich mobile and wearable devices allow us to seamlessly capture an increasing amount of our daily experiences in digital format. This process can support human memory by producing "memory cues", e.g., an image or a sound that can help trigger our memories of a past event. However, first-person captures such as those coming from wearable cameras are not always ideal for triggering remembrance. One interesting option is thus to combine our own capture streams with those coming from co-located peers, in or even infrastructure sensors (e.g., a surveillance camera) in order to create more powerful memory cues. Given the significant privacy and security concerns of a system that shares personal experience streams with co-located peers, we developed a tangible user interface (TUI) that allows users to in-situ control the capture and sharing of their experience streams through a set of five physical gestures. We report on the design of the device, as well as the results of a user study with 20 participants that evaluated its usability and efficiency in the context of a meeting capture. Our results show that our TUI outperforms a comparable smartphone application, but also uncovers user concerns regarding the need for additional control devices.

Mobile and wearable devices allow people to capture different aspects of their life experiences (e.g. family holidays, work meetings, running activities, etc.) in the form of photos, videos, physiological data, etc. An interesting avenue to explore is the usage of such captured experiences to support and augment human memory. Experiences of different events can be used to generate retrieval memory cues in order to trigger recall of those recorded events. In addition, captured experiences can be shared with other (co-located) people of the same event. The focus of this work is on understanding the privacy challenges with regard to using and sharing captured experiences for memory augmentation purposes. With the ultimate goal of an usage control model for the protection of personal memory cues, here we provide insights on: how sharing captured experiences is different from sharing experiences in social media networks, and what are some challenges in designing an usage control model for memory cues.