Learning: Episodic

Episodic learning is a change in behavior that results from an experience that is encoded in episodic memory—the long-term memory of unique events from one's own life.

Episodic learning derives from the creation of an episodic memory. It is a type of experiential learning that is unique, in that it is not modified or filtered during the learning process; rather, it derives directly from the experience. Examples of this type of episodic learning are a fear of water after a near-drowning, a fear of dogs after being bitten, or a fear of flying after a near-miss in an airplane.

Episodic, perceptual, and semantic (information) learning and memory represent the three types of explicit learning and retrieval. Because new facts and ideas that are learned from experiences are encoded in episodic memory, to a large extent, semantic memory is derived from episodic learning. This may be the result of a gradual transition, in which the episodic memory loses its emotional component and its association with a particular event, and the learned information becomes generalized into semantic memory.

Episodic memory

The psychologist Endel Tulvig first defined episodic memory in 1972 as the difference between knowledge (semantic memory) and remembering the past. Episodic memory is one's personal history and, as such, is central to a person's individual identity. Examples of episodic memory are the details of last night's dinner or where one parked the car. People remember where they were when they first heard of the 9/11 terrorist attacks on the World Trade Center because the experience of hearing about the attacks was recorded in their episodic memory. In contrast, the events surrounding those attacks are knowledge that is stored in semantic memory. Episodic memory and semantic memory are types declarative memory— memories that are consciously recalled. Although they are functionally related, episodic and semantic memories involve different brain systems. Furthermore, studies suggest that the details of an episodic memory can be recognized even without conscious recall of the event.

Episodic learning requires three memory-processing steps.

The hippocampus and surrounding areas of the brain are central to episodic learning. These regions work together with other brain networks, especially the default mode network, which involves several areas of the brain including the frontal and parietal regions. The thalamus, mammillary bodies, and amygdala are also involved in episodic memory. Episodic memories are first processed in the hippocampus and then consolidated and stored in the neocortex. Different elements of the event are distributed to visual, olfactory, and auditory areas of the brain. The hippocampus connects these distributed elements to form a complete memory of the event. The amygdala strengthens encoding and consolidation by emphasizing the emotional components of events. Episodic retrieval activates the right prefrontal cortex, as well as the hippocampus and other areas.

Episodic learning in children

KEY TERMS

Amygdala; pl. amygdalae—
The almond-shaped basal ganglia in each cerebral hemisphere; part of the limbic system that is involved in the emotional components of episodic memory and learning.
Episodic memory—
Memory of personal experiences and events.
Hippocampus—
A part of the brain's limbic system that is involved in memoryformation and learning.
Infantile amnesia—
The inability of older children and adults to recall feelings, experiences, and events from infancy and early childhood.
Semantic memory—
Memory of information.
Thalamus—
The largest portion of the diencephalon, which relays impulses, especially sensory impulses, to and from the cerebral cortex and is involved in episodic memory and learning.

Between the ages of three and five, infantile amnesia disappears, and episodic memories can be recalled for longer periods, even into adulthood. It has been suggested that three-year-olds have good retention of episodic memory for short periods, and that episodic memory skills continue to develop throughout early and middle childhood, with episodic memory retention steadily improving. Nevertheless, studies indicate that younger children can remember events that occurred well before age three. In fact, some children under age ten have accurate memories of events that occurred when they were less than one year or even less than one month of age. This suggests that episodic learning is an important process in infants as well as young children and adults.

Impairment

Many neurologic conditions and disorders can affect episodic learning and memory. Impairment of episodic memory is a hallmark of Alzheimer's disease, which often originates in the hippocampus and affects the default mode network. Furthermore, any condition that disrupts attention—such as head injury, brain tumors, Lewy body dementia, or delirium— can impair episodic learning by interfering with encoding. Alcohol, medications, anxiety, depression, posttraumatic stress disorder (PTSD), or pain can also disrupt episodic memory and learning.

Resources

BOOKS
PERIODICALS

Cyr, Andre´ e-Ann, and Nicole D. Anderson. “Mistakes as Stepping Stones: Effects of Errors on Episodic Memory Among Younger and Older Adults.” Journal of Experimental Psychology 41, no. 3 (May 2015): 841.

Mullally, Sine´ ad L., and Eleanor A. Maguire. “Learning to Remember: The Early Ontogeny of Episodic Memory.” Developmental Cognitive Neuroscience 9 (July 2014):12–29. http://www.sciencedirect.com/science/article/pii/S1878929314000024 (accessed September 1, 2015).

WEBSITES

UCSF Memory and Aging Center. “Episodic Memory.” Brain 101: Topics in Neuroscience. University of California, San Francisco. December 8, 2014. http://memory.ucsf.edu/brain/memory/episodic (accessed September 1, 2015).

ORGANIZATIONS

American Psychological Association, 750 1st St. NE, Washington, DC, 20002-4242, (202) 336-5500, (800) 374-2721, http://www.apa.org .