The interference model theory is a psychological theory that suggests that forgetting occurs because memories interfere with each other. According to this theory, when we try to remember something, other memories that are similar or related to the target memory can interfere with the retrieval process, making it more difficult to access the desired information. This interference can occur in two ways: proactive interference, where old memories interfere with the retrieval of new memories, and retroactive interference, where new memories interfere with the retrieval of old memories. The interference model theory helps to explain why we sometimes struggle to remember certain information, even though it may have been stored in our memory.