The Tip-of-the-Tongue phenomenon
The process of speech production occurs relatively effortlessly, despite complex cognitive processes that underlie word retrieval. However, sometimes these processes do break down and result in a production failure called a tip-of-the-tongue (TOT) state. TOTs are temporary word-finding problems, characterized by an inability to retrieve a word at an intended time despite a strong feeling of knowing the word. TOTs are of particular relevance to older adults, who report having more TOTs and rate them as their most frustrating cognitive failure. The present chapter reviews the relevant literature on age-related changes observed in the TOT phenomenon, with a specific investigation of factors that increase the likelihood of older adults having TOTs as well as those that promote or inhibit TOT resolution. We begin by defining TOTs and their underlying causes in the context of theories of language production. We then discuss empirical findings that examine older adults’ disproportionate vulnerability in experiencing TOTs, the ways in which the incidence and resolution of TOTs can be exacerbated or mitigated, the particular susceptibility of proper names to TOTs, and comparisons of healthy older adults with adults with some clinical memory disorders. The chapter concludes with a brief discussion of suggestions for future research directions that may shed light on other unique contributors to these language production failures in old age.