A source-monitoring error is a type of memory error where the source of a memory is incorrectly attributed to some specific recollected experience. For example, individuals may learn about a current event from a friend, but later report having learned about it on the local news, thus reflecting an incorrect source attribution. This error occurs when normal perceptual and reflective processes are disrupted, either by limited encoding of source information or by disruption to the judgment processes used in source-monitoring. Depression, high stress levels and damage to relevant brain areas are examples of factors that can cause such disruption and hence source-monitoring errors. Introduction One of the key ideas behind source-monitoring is that rather than receiving an actual label for a memory during processing, a person's memory records are activated and evaluated through decision processes; through these processes, a memory is attributed to a source. Source-monitoring relies heavily on the individual's activated memory records; if anything prevents encoding the contextual details of an event while it happens, relevant information will not be fully retrieved and errors will occur. If the attributes of memory representations are highly differentiated, then fewer errors are expected to occur and vice versa. Two cognitive judgment processes exist regarding source-monitoring; these are commonly called heuristic and systematic judgement processes. Heuristic judgements Heuristic judgements are made quickly without the conscious awareness of the individual, making use of perceptual, contextual, and other event-related information. These occur more frequently because they are efficient and occur automatically without the individual putting forth conscious effort. A decision is made about a source when relevant information is of a certain significance and the memory occurring at a certain time or place makes sense logically; errors then occur based on the amount of information stored at encoding or the way that an individual's brain makes decisions based on prior experiences. Within the source-monitoring framework, "heuristic" is a type of decision process; this term is directly related to the psychological heuristics. Systematic judgements Systematic judgements are decision processes whose procedures are accessed consciously by the individual; the same types of information used in heuristic judgements are also used in systematic judgements. In this process, all memory-relevant information is retrieved from memory and assessed deliberately to determine whether a memory is likely to have come from a specific source. Systematic judgements occur less frequently in source judgements because they are slow and require a lot