This is a part of long-term memory with the duty of keeping facts and common knowledge. In other words, it refers to concepts and facts that people have accumulated throughout their lives. Typically, semantic memory includes matters commonly considered common knowledge. They’re neither immediately nor exclusively drawn from personal experiences. Some examples of semantic memories are:
- Recalling that Shakespeare was born in April 1564.
- Knowing that giraffes and elephants are both mammals.
- Recalling the type of food people in China eat.
Semantic memory is related to facts and continues to grow as people age. Since it has no connection with personal experiences or emotions, it’s different from episodic memory. For example, knowing what happened on 9/11 in the U.S. is semantic memory but remembering where an individual was when 9/11 happened is episodic memory for that person. Another example of semantic memory is knowing what a cat is, while recalling when an individual brought his pet cat home is episodic memory. Thus, episodic memory is specific to an individual, such as his marriage or the birth of a child. However, semantic memory is more general, which can be shared worldwide.
Conditions and consequences of the stored information retrieval are also different between semantic and episodic memory. The circumstances leading to the retrieval of episodic memory can add to or change that memory, which is why such memory gets lost more easily. In contrast, semantic memory remains unchanged with retrieval.
For children and students, semantic memory is extremely vital as it allows them to remember the facts they’re learning and getting evaluated. Even for professionals and those in the workforce, semantic memory is crucial as it lets them retain and retrieve information essential to perform their jobs. For others, semantic memory is important because it allows them to know the surrounding world. If they didn’t have semantic memory, they wouldn’t know that the grass looks green, what a computer or a telephone is, or birds can fly.
There are three chief ways of encoding that people use to assign information to semantic memory. They are meaning, acoustic, and visual. This means people may encode information to semantic memory by
- relating them to something else that’s meaningful in their memory;
- hearing the information repeatedly; and
- through pictures or reading numbers and words.
In the brain, semantic memory could be organized in two different ways for retrieval – thematically and taxonomically. Cross-categorical relationships help thematical organization of information, while hierarchy helps taxonomically organized information. A recent study revealed that children and young adults are likely to use the thematical organization of semantic memory, while adults tend to opt for the taxonomical organization. Past studies have also indicated that with time and as people mature, the organization of semantic memory changes.
Retrieval processes of semantic memory have also triggered a lot of curiosity. Though some neuroscientists and psychologists speculated it to be based on the exact facts, a recent study has found that it’s relational. For example, when a person says that an eagle can fly, it’s because he knows that birds fly, and eagles are birds, which is why they fly.