What is the difference between episodic and semantic memory?

Episodic memory holds personal events tied to a time and place, which you recall by mentally re-experiencing them: your last birthday, this morning's breakfast. Semantic memory holds facts, word meanings and general knowledge with no memory of when or where you learned them: that Paris is the capital of France, what a dog is. Both are kinds of explicit (declarative) long-term memory.

What is episodic memory?

Episodic memory is memory for personally experienced events: what happened, where and when. The psychologist Endel Tulving, who proposed the term in 1972, later described it as a kind of mental time travel, in which remembering comes with the feeling of being back in the moment.

What is semantic memory?

Semantic memory is your store of general knowledge: facts, concepts, word meanings and how the world works. You know these things without remembering the occasion on which you learned them. Much of it is shared with other people, which is why a quiz question has one right answer.

What are examples of episodic and semantic memory?

Episodic: remembering your first day at a new job, the last film you saw in a cinema, or where you parked this morning. Semantic: knowing that water boils at 100 °C at sea level, the meaning of the word 'reluctant', or that your best friend's birthday is in May. Knowing that you went to Rome in 2019 is semantic; recalling standing in the rain outside the Colosseum is episodic.

Can you lose one type of memory but keep the other?

Largely, yes. The amnesic patient K.C. kept much of his general knowledge but could not recollect a single personally experienced event. Three young people with hippocampal damage from early childhood attended mainstream schools and reached low-average to average levels of language and factual knowledge despite severe amnesia for everyday events. In semantic dementia the pattern runs the other way: word meanings and knowledge erode while day-to-day memory is relatively spared.

Which memory type is linked to IQ?

Semantic memory, mainly. The vocabulary and general-knowledge parts of IQ tests, which make up crystallized intelligence, draw on what you have stored in semantic memory. Episodic memory, remembering what happened to you, is not what an IQ test scores.

Episodic vs Semantic Memory: Differences, Examples

Episodic memory is memory for events you lived through, tied to a time and place; semantic memory is general knowledge, such as facts and word meanings, that you know without remembering when you learned it. Recalling your last birthday dinner is episodic; knowing that a birthday comes once a year is semantic. Both are kinds of explicit long-term memory, the kind you can consciously bring to mind, and the distinction was first drawn by the psychologist Endel Tulving in 1972.

Episodic vs semantic memory at a glance

What it holds: episodic memory holds personal events (what happened, where and when); semantic memory holds facts, concepts and the meanings of words.
How it feels: episodic recall feels like re-living (“I remember”); semantic recall feels like knowing (“I know”).
Context: an episodic memory carries its time and place with it; a semantic memory has lost them.
Whose it is: episodic memories are yours alone; much semantic knowledge is shared with everyone who learned the same things.
How it changes with age: in a large Swedish study, episodic memory held steady until about 60 and then declined, while semantic memory rose slightly until about 55 and fell less afterwards (details below).

Both sit inside the larger map of memory types described on our page about long-term memory, alongside the implicit kinds, such as skills and habits, that you use without recalling them.

Examples of each

Episodic: where you parked this morning; your first day at a new job; the conversation you had at dinner last night; the moment you heard some big piece of news.
Semantic: that water boils at 100 °C at sea level; what the word “reluctant” means; the rules of chess; that your best friend’s birthday is in May.
The tricky middle: knowing that you went to Rome in 2019 is a fact about your life, so it counts as semantic (sometimes called personal semantic memory). Recalling standing in the rain outside the Colosseum, with the smell and the sound, is episodic.

Tulving’s idea: remembering versus knowing

Tulving first defined episodic memory by what it contains, events located in time. Over the following decades he redefined it by how it feels. In a 1985 paper he tied episodic memory to what he called autonoetic (self-knowing) consciousness, the sense of travelling back in time to an experience, and semantic memory to noetic (knowing) consciousness, the awareness of a fact without re-living anything. The same paper introduced a way of measuring the difference that researchers still use: after recognising an item, people say whether they “remember” the moment of learning it or simply “know” it was there. By his 2002 review, Tulving described episodic memory as a system that lets people remember their own past, built on a sense of self and of subjective time.

The evidence that they can come apart

The strongest case for two kinds of memory comes from people who lost one and kept the other.

K.C. A motorcycle accident left this Canadian man with widespread brain damage including large lesions of both hippocampi. His researchers describe his amnesia for new material as as severe as any on record. From his life before the accident, he kept a good deal of general knowledge, including facts about himself, but could not recollect a single personally experienced event.
Developmental amnesia. In 1997 a team at University College London described three young people whose hippocampal damage occurred at birth, by age 4 and at age 9. All three had pronounced amnesia for the episodes of everyday life, yet attended mainstream schools and reached low-average to average levels of speech and language, literacy and factual knowledge. The authors concluded that only the episodic part of memory fully depends on the hippocampus.
Semantic dementia runs the other way. In this condition, described in five patients in 1992, knowledge of words and objects gradually dissolves while autobiographical and day-to-day memory is relatively retained. A 2007 review opens with a patient who could still direct his wife along a rarely travelled country road, then pointed at sheep in a field and asked what those things were. The damage centres on the front of the temporal lobes, which this research suggests act as a hub for concepts.

Not every case splits so cleanly. The famous patient H.M., described on our long-term memory page, struggled to learn new facts as well as new events after his operation, and Larry Squire and Stuart Zola argued in 1998 that the medial temporal lobes support both kinds of new learning. The mainstream view today sits between the two positions: the systems are distinct, but not separate.

How the two work together

In everyday life the two systems constantly feed each other. What you already know shapes what you notice and store about a new event, and repeated experiences gradually turn into general knowledge: after many trips to the same café you know where it is without recalling any one visit. A 2010 review by Daniel Greenberg and Mieke Verfaellie collected neuropsychological evidence that each kind of memory affects the other both when memories are formed and when they are retrieved. A 2019 review by Louis Renoult and colleagues concluded that the two are “inextricably intertwined” and share much of their brain basis, yet keep a measure of distinctiveness.

How episodic and semantic memory change with age

The clearest data come from the Betula study in Umeå, Sweden. Michael Rönnlund and colleagues followed 829 adults aged 35 to 80 over five years and compared them with a matched group of 967 people to control for practice effects. Comparing age groups at a single point in time suggested a gradual episodic decline across adulthood, but following the same people showed no episodic decline before 60. Semantic memory showed small gains until about 55 and smaller losses in old age than episodic memory. Differences in education between generations largely explained why the two methods disagreed, which is a useful caution whenever you see a chart of memory by age.

Which kind of memory do IQ tests use?

Mostly semantic. Vocabulary, general information and similarity questions, the core of what psychologists call crystallized intelligence, measure knowledge stored in semantic memory, which is one reason crystallized scores keep rising well into middle age. Episodic memory, remembering what happened to you, is not something an IQ test scores, and holding information for a few seconds while you reason with it is a different system again, covered on our page about working memory. A rich store of knowledge helps on many tasks, but using it to solve a new problem is a separate ability, as our guide to the g factor explains.

Trust and scope notes

This page summarises published research for general information, with figures taken from the studies listed below. It is not medical advice: memory problems that are new, worsening or worrying deserve a conversation with a doctor, and no online test can assess them. The IQ Revealed test is an online reasoning test of 40 original items for adults aged 18 and over; it is not a clinical assessment and it does not measure memory. Our guide to how IQ tests work explains what an online test can and cannot tell you.

IQ Revealed is not affiliated with, endorsed by or connected to the researchers, universities, journals or publishers named on this page. Names are used only to identify the research being described.

Episodic vs Semantic Memory: Differences, Examples and the Brain