Patient short term memory performance was shown to be 35-37% improvement over their baseline measurements. This is the first time known to the scientists in which a patient’s own brain cell code/pattern for memory has been identified to make existing memory work better potentially restoring memory loss.
The scientists focused on improving episodic memory which is the most common form of loss in Alzheimer’s disease, injury and stroke; and is information that is new and useful for short periods of time including things such as where you parked your car while out and about on any given day. Reference memory is more important information held and used for long periods of time such as relevant things learned in school or at work.
Epilepsy patients were enrolled in this study who were participating in a diagnostic brain mapping procedure which had used surgically implanted electrodes in the brain to pinpoint seizure origins. Using electronic prosthetics system based on multi in and output nonlinear mathematical model researchers influenced firing patterns of various hippocampus neurons which are involved in making new memories in 8 patients. Neural patterns were recorded while participants performed computerized memory tasks such as being shown images after brief delays and then asked to identify the initial image out of 4-5 displayed on the screen. Recordings were analyzed from the correct responses and then synthesized a MIMO based code for correct memory performance. The code was then played back to those patients while performing image recall testing, and in this test patients episodic memory showed 37% improvements over baseline measurements.
Participants in a second test were shown distinctive photographic images followed by delays and asked to identify the 1st out of 4-5 photos displayed on the screen. Memory trials were repeated using different images while neural patterns were recorded to identify and deliver correct answer codes/patterns. After a longer delay participants were shown sets of 3 pictures at a time with new and original photos and asked to identify original photos from 75 minutes previous, when stimulated with correct answer codes participants showed 35% improvements.
Scientists say that they have displayed that they have successfully tapped into a patient memory content and used it to reinforce memory fed back to the patient, and that even when memory is impaired it is possible to identify neural firing patterns indicating correct memory information separate from incorrect, to then feed the correct patterns to assist patient brain into forming accurate new memories, not as replacement for function but as a booster.
Researchers have been working to determine if memory skill people still have can be improved, and hope to be able to help people hold onto specific memories such as an important phone number, where they live, or what their family members look like when overall memory begins to fail. This study was built on upwards of 20 years of preclinical research on memory codes. Preclinical work applied the same kinds of stimulation to restore and facilitate memory in model animals using the MIMO system developed at USC.
