Redox dopamine-modified chitosan memory films with forgetting behavior

Memory and forgetting in the human brain are multidimensional, synergistic, and dynamic processes involving neurophysiology and cognitive processes. To overcome the limitations of static and non-stimulation responsiveness of traditional dry and rigid information storage media, which are static and unresponsive to external stimuli, hydrogels with wet and soft characteristics with brain tissue have become one of the research hotspots in recent years for applications in information storage and dynamic memory materials. Inspired by the processes of memory forgetting and relearning in the human brain in cognitive psychology, we propose a structurally simple dopamine-chitosan memory film with forgetting capability. This memory film was fabricated through a two-step electrodeposition and electrooxidation process, simulating the brain's slow forgetting (long-term memory) and relearning mechanisms based on the gradual oxidation and reducibility of dopamine over time. The information storage of memory films was quantified by detecting response currents via electrochemical methods, successfully reproducing key features of the Ebbinghaus forgetting curve and the spaced repetition learning curve (antagonistic forgetting curve). The results show that the memory film maintains good long-term memory retention and repetitive learning functionality, potentially inspiring future studies on brain-like memory forgetting using wet, soft materials and redox-active compounds.