Involuntary memory

In psychology and neuroscience, implicit memory is one of the two main types of long-term human memory. It is acquired and used unconsciously, and can affect thoughts and behaviours. One of its most common forms is procedural memory, which allows people to perform certain tasks without conscious awareness of these previous experiences; for example, remembering how to tie one's shoes or ride a bicycle without consciously thinking about those activities. The type of knowledge that is stored in implicit memory is called implicit knowledge, implicit memory's counterpart is known as explicit memory or declarative memory, which refers to the conscious, intentional recollection of factual information, previous experiences and concepts. Evidence for implicit memory arises in priming, a process whereby subjects are measured by how they have improved their performance on tasks for which they have been subconsciously prepared. Implicit memory also leads to the illusory truth effect, which suggests that subjects are more likely to rate as true those statements that they have already heard, regardless of their truthfulness.