Researchers from the University of Cambridge have demonstrated that people can quickly learn to use a controllable, prosthetic “Third Thumb” to manipulate objects.
The study tested the device on 596 participants ranging in age from 3 to 96 at the Royal Society Summer Science Exhibition in 2022.
Remarkably, 98% of participants were able to use the Third Thumb within the first minute of testing. The Third Thumb, developed by Dani Clode within Professor Tamar Makin’s lab at the MRC Cognition and Brain Sciences Unit, enhances the wearer’s range of movement, grasping capability, and carrying capacity. It is worn on the opposite side of the palm from the user’s natural thumb and is controlled by pressure sensors placed under each big toe. During the exhibition, participants were given up to a minute to familiarize themselves with the device and complete basic tasks such as moving pegs and foam objects.
Controllable prosthetic thumb learning speed
Most participants adapted quickly, with no significant performance differences between genders or handedness. However, there was a slight decline in performance with increasing age among older adults, and younger children found the device more challenging to use.
Professor Makin commented on the broader implications of this technology, stating, “Technology is changing our very definition of what it means to be human… it’s vital that we consider how they can help all people equally, especially marginalized communities who are often excluded from innovation research and development.” The study underscores the importance of inclusive design in technology development to ensure new technologies are accessible and functional for a wide range of users.
Co-author Lucy Dowdall emphasized that for motor augmentation to be successful, it must integrate seamlessly with users’ motor and cognitive abilities, taking into consideration diverse factors such as age, gender, and lifestyle. The research team hopes that the insights gained from this large-scale, inclusive study will pave the way for further advancements in human-machine interaction and motor augmentation devices.
The study was funded by the European Research Council, Wellcome, the Medical Research Council, and the Engineering and Physical Sciences Research Council, and was published in Science Robotics.
