Tip of the tongue (or TOT) is the phenomenon of failing to retrieve a word from memory, combined with partial recall and the feeling that retrieval is imminent. The phenomenon's name comes from the saying, "It's on the tip of my tongue." The tip of the tongue phenomenon reveals that lexical access occurs in stages.
People experiencing the tip-of-the-tongue phenomenon can often recall one or more features of the target word, such as the first letter, its syllabic stress, and words similar in sound and/or meaning. Individuals report a feeling of being seized by the state, feeling something like mild anguish while searching for the word, and a sense of relief when the word is found. While many aspects of the tip-of-the-tongue state remain unclear, there are two major competing explanations for its occurrence, the direct-access view and the inferential view. The direct-access view posits that the state occurs when memory strength is not enough to recall an item, but is strong enough to trigger the state. The inferential view claims that TOTs aren't completely based on inaccessible, yet activated targets; rather they arise when the rememberer tries to piece together different clues about the word. Emotional-induced retrieval often causes more TOT experiences than an emotionally neutral retrieval, such as asking where a famous icon was assassinated rather than simply asking the capital city of a state. Emotional TOT experiences also have a longer retrieval time than non-emotional TOT experiences. The cause of this is unknown but possibilities include using a different retrieval strategy when having an emotional TOT experience rather than a non-emotional TOT experience, fluency at the time of retrieval, and strength of memory.
TOT states should be separated from FOK (feeling of knowing) states. FOK, in contrast, is the feeling that one will be able to recognize - from a list of items - an item that is currently inaccessible. There are still currently opposing articles of the separability of the process underlying these concepts. However, there is some evidence that TOTs and FOKs draw on different parts of the brain. TOTs are associated with the anterior cingulate, right dorsolateral prefrontal cortex, and right inferior cortex while FOKs are not.
An occasional tip-of-the-tongue state is normal for people of all ages. TOT becomes more frequent as people age. TOT is only a medical condition when it becomes frequent enough to interfere with learning or daily life. This disorder is called anomic aphasia when acquired by brain damage, usually from a head injury, stroke, or dementia.