Page "Recall (memory)" Paragraph 59

Involuntary semantic memory retrieval ( ISM ), or " semantic-popping ", occurs in the same fashion as IAM retrieval.

However, the elicited memory is devoid of personal grounding and often considered trivial, such as a random word, image, or phrase.

ISM retrieval can occur as a result of spreading activation, where words, thoughts, and concepts activate related semantic memories continually.

When enough related memories are primed that an interrelated concept, word, thought, or image " pops " into consciousness and you are unaware of the extent of its relatedness within your memory.

Spreading activation is thought to build over a period of many hours, days, or even weeks before a random semantic memory " pops ".