Involuntary memory
This type includes involuntary memories as they arise in everyday mental functioning, which are characterized by their element of surprise: they appear to come into conscious awareness spontaneously.
[5] According to Mace, this suggests that autobiographical memories are organized primarily conceptually (“experiential type concepts: people, places, locations, activities, etc.”), while temporal associations are not retained over time the same way.
The troubling nature of such memories makes these occurrences important to clinical researchers in their studies of psychiatric syndromes such as post-traumatic stress disorder.
Born in Bremen, Germany in 1850, Hermann Ebbinghaus is recognized as the first to apply the principles of experimental psychology to studying memory.
Ebbinghaus also made the key note that these involuntary reproductions are not random or accidental; instead, "they are brought about through the instrumentality of other immediately present mental images," under the laws of association.
[2] Marcel Proust was the first person to coin the term involuntary memory, in his novel À la recherche du temps perdu (In Search of Lost Time or Remembrance of Things Past).
Mace, in one of his recent studies, wanted to test the notion that basic cognitive activities, such as thinking about the past, may prime involuntary memories.
These areas were increasingly engaged during intentional retrieval, suggesting that one function of this region may be to align remembering to aid with current behavioral goals.
The second study found that the medial temporal lobe, the posterior cingulate gyrus, and the precuneus, are activated during retrieval success with or without executive control seen within the right dorsolateral prefrontal cortex.
This is significant because it suggests that voluntary and involuntary retrieval are largely not mediated by separate cortical networks, which raises questions for future research of what distinguishes the two sub-components of memory, if not cognitive pathways and brain activation areas.
Further, it might be explored whether these similarities in cognitive mechanism reflect shared properties and impacts of the recalled memories themselves, regardless of intentionality of retrieval.
It is suggested that the activation seen in left dorsolateral prefrontal cortex during involuntary memory recall reflects the attempt to prevent the recollected material from interfering with the semantic judgment task.
The reminiscence bump is the phenomenon where in memories formed during adolescence and early adulthood are more commonly remembered than those throughout other periods in life.
It has been found that memories associated with stronger emotions (e.g.: being happy at your wedding) are more easily remembered and quickly recalled,[18] as are those formed during moments of intense stress.
The main psychological consequences of this include re-experiencing the traumatic event (through both intrusive thoughts and images), avoidance of trauma-related stimuli, and increased arousal levels.
When it comes to involuntary memory, researchers are mainly interested in the concept of these trauma-related intrusions, which generally involved some form of re-experiencing the event, including a sensory component (e.g., imagery in any modality be it visual, auditory etc.).
These intrusions, often termed "flashbacks", make the victim feel as though they are reliving the trauma, and cause high levels of emotional arousal, and the sense of an impending threat.
Typically, they are parts of the traumatic event that were most salient at the time, known as "hotspots" and have the definitive feature that they cause high levels of emotional distress, and may be difficult to recall deliberately.
[2] A common example is one in which someone who has the victim of a car crash, upon hearing the screeching of tires experiences a flashback of their own collision, as if they are back at the original event.
Stressful and traumatic events, which may manifest as involuntary memories called flashbacks, may trigger a wide range of anxiety-based and psychotic disorders.
In addition, those who have been diagnosed with PTSD and have an identified form of trauma show positive symptoms of psychosis such as delusions and/or hallucinations.
