CogBlog – A Cognitive Psychology Blog

It’s a parasite. Small. Drills its way into unknowing individuals’ feet and proceeds to circulate their bloodstream. Common in areas with poor sanitation. I know this parasite from my global public health presentation from just last year. It starts with an ‘S’, maybe even a shhh sound? How could I not remember this? “Schistosomiasis”, my professor stated after what seemed like several frustrating minutes of attempting to recall the name for this parasite.

Why couldn’t I remember a word with which I am very familiar? One with which I spent hours researching on various databases, the CDC, even Wikipedia? It’s called the tip of the tongue (TOT) phenomenon, and if you’re anything like me, you likely experience this ever so maddening effect more frequently than you’d like. I’ve long since wondered about this phenomenon as whenever it happens to my Mum, she claims that she’s “losing [her] marbles” or is developing dementia. Does this mean that I’m developing dementia, too? Cognitively speaking, what is going on when you experience a TOT? But seriously, what is a TOT, anyways?

Tip of the tongue effect as illustrated by Brad Carey (2010).

Simply put, the tip of the tongue phenomenon is the psychological term used to describe the common feeling of a word being on “the tip of your tongue”. Now, if you know even the slightest bit about the human brain or speech production, you probably know that complex patterns of neurological firings are actually directing your tongue on what movements to make in order to speak; so no, the word isn’t actually sitting patiently on your tongue, waiting to be said. However, this phenomenon gets it unique name from the feeling that you know you know the word, but you just can’t quite produce it fully. This means that you will only ever experience a TOT with a word with which you are familiar (a word that you know you know!) (Brown & McNeil, 1996). For example, unless you are well read in genetics research, the name of the gene responsible for wing production in Drosophila is not available to be remembered as you never learned it; therefore, you are not experiencing a TOT. In the case of TOTs, the word must be available (meaning that it is stored somewhere in your memories) but for one reason or another, is currently inaccessible (you are unable to get to it). This inability to access the word, despite the fact that you know you know it, produces the frustrating feeling of the word sitting on the tip of your tongue.

Something which makes matters worse, in my opinion, is the fact that often times a TOT will be accompanied by a partial recall of the word. What does this mean? While you are experiencing a mind block and are unable to remember the entire word, you might be able to remember the first letter or two, an affix, or a syllable (Brown & McNeil, 1996). This form of partial recall is known as ‘generic recall’ in the literature and research suggests that it is pretty common. In fact, in one study it was found that 57% of the time, participants were able to correctly identify the first letter in all of the induced TOTs (more on study design later) (Brown & McNeil, 1996). In the case of schistosomiasis, I experienced generic recall as I knew that the word started with an ‘S’ and I was pretty sure that it started with a shhh sound. I find this generic recall to be pretty annoying as for me, it makes me realize just how close I am to remembering the word properly. I don’t know about you, but this leaves me wondering if we do have a memory for these words, and are often times able to partially produce it, why are we unable to generate the entire word?

There are two main theories that have been postulated in an attempt to understand this common experience. The first theory, the incomplete-activation hypothesis, implies the target word is not being adequately stimulated and instead, other similar sounding words are being remembered. A real-world example of this theory would be if you were attempting to recall the first name of the lead in Grey’s Anatomy (Meredith), but were instead producing other, similar sounding names, like Margaret. Using this theory, Meredith is receiving inadequate stimulation to produce recall and instead Margaret, which is also being stimulated due to its shared phonological characteristics with ‘Meredith’, is coming to mind (Meyer & Bock, 1992). The second theory for the tip of the tongue phenomenon is known as the blocking theory. In this theory, words that sound similar to the target word come to mind and actually obstruct remembering of the target word (Meyer & Bock, 1992). In this case, ‘Margaret’ is being incorrectly recalled and is blocking the cognitive recall of the correct word, ‘Meredith’. As a big Grey’s fan, I can tell you Margaret is not Dr. Grey’s first name. There are many studies in support of both of these theories; if you’d like to read some of them, a classmate of mine wrote a more detailed blog post exploring these theories and research that supports them. Click here to check these out!

Who is this? (Source: Business Insider, 2014)

Okay, so at this point, you’re probably wondering how cognitive psychologists can study TOTs; how can they induce this phenomenon in unknowing participants? Many studies will provide participants with images of famous faces and novel faces and ask them to indicate if they can recall their name. For instance, you’d be provided with the following picture and be asked to identify her. Go ahead, try with the image to the left. Could you remember that face? If you couldn’t, was it because (a) you’ve never seen her face before, (b) you’ve seen her before but do not remember her name, or (c) her name is on the tip of your tongue. In research, participants must also indicate whether they were experiencing a TOT, if the face was unknown, or if the face seemed familiar but could not be remembered (Huijbers et al. 2016). Other studies exploring TOTs have provided participants with questions prompting written definitions (“what is the name of the building where one can view projected images of celestial bodies on the inner surface of a dome?”) and written descriptions (“what is the name of the large waterfall in Zambia that is one of the Seven Wonders of the World?”) (Salthouse & Mandell, 2013). (To read more about this specific study and an interview from the lead author, try checking out this news article). Go ahead, try these, too. I’ll put the answers at the bottom, after the references (don’t cheat!). If you don’t know the answer, try to think about why that might be. Are you experiencing a TOT..?

Broad map of brain regions. Pre-frontal regions are blue, whereas posterior regions are green, yellow, and pink (Source: Wikipedia).

An important finding from TOT research suggests that as with many errors in cognitive processes, the frequency of TOT phenomena increases with age. Across the three common methods used to study TOTs (written descriptions, written definitions, and picture identification), Salthouse & Mandell (2013) found that with the exception of easy and hard definitions, older age was associated with more TOT experiences. As with my Mum, increased TOT experiences can provoke fears of developing neurodegenerative diseases, including the dreaded Alzheimer’s disease (Huijbers et al. 2016). However, recent research where older adults are tasked with providing the name of well-known celebrities while in an MRI scanner. The scans demonstrate that age-related memory declines are a result of alterations in posterior brain regions (think: back of the head), while age-related changes in cognitive controls are a result of changes in the pre-frontal regions (think: forehead). What does this mean? Ultimately, this discrepancy in activated brain regions suggests that there is likely a difference between age-related memory changes and age-related cognitive changes of which result in increased TOT experiences with aging.

One theory that I am fond of in support of this finding is the incremental-knowledge theory. This theory stipulates that older adults experience more TOTs not because of a decline in memory, but because older adults simply have a greater vocabulary than do children; and with a greater vocabulary comes a greater likelihood that a word will be temporarily unavailable (Schwartz & Fraizer, 2005; Huijbers et al., 2016). This research is supported by Salthouse (1991; as cited in Schwartz & Fraizer, 2005) of which suggests that older adults do have a larger vocabulary than do younger adults. Furthermore, Dahlgreen (1998; as cited in Schwartz & Fraizer, 2005) argues that it is not age itself that is responsible for this relationship, but it is the increased knowledge of the world that comes with aging; this claim is supported by research that found that same-age adults with a larger vocabulary experience more TOTs than do adults with a lesser vocabulary (Schwartz & Fraizer, 2005). In support of the MRI findings, this incremental-knowledge theory offers an explanation for the discrepancy of activated brain regions. Likewise, another theory stipulates that TOTs increase with age in an attempt to compensate for memory decline, which comes with aging (Huijbers et al., 2016). In both cases, however, increased TOTs with aging are not a direct result of memory decline and thus should not be feared as an indication of such.

The main takeaway from this blog post, you might ask? Don’t be fearful or embarrassed when you’re experiencing a TOT! Remember: according to the incremental-knowledge theory, a TOT might actually be a reflection of your profound vocabulary; take it as a compliment! If you’re interested in reading more about the tip of the tongue effect, you should check out this blog post on TOTs and gesturing. I’m also going to re-link (here) the blog post aforementioned that explores the theories more in-depth. My advice to you is that next time you’re experiencing a TOT, spend some time with yourself attempting to properly recall the target word and don’t just Google it. Overreliance on technology and the ability to immediately get an answer to just about every question we could ever have isn’t always the best thing. You should read more about the Google Effect here and how its ability to cause cognitive deficits.

References:

Brown, R., & McNeill, D. (1966). The “tip of the tongue” phenomenon. Journal of Verbal Learning and Verbal Behavior, 5(4), 325-337.

Huijbers, W., Papp, K. V., LaPoint, M., Wigman, S. E., Dagley, A., Hedden, T., … & Sperling, R. A. (2016). Age-related increases in tip-of-the-tongue are distinct from decreases in remembering names: a functional MRI study. Cerebral Cortex, 27(9), 4339-4349.

Meyer, A. S., & Bock, K. (1992). The tip-of-the-tongue phenomenon: Blocking or partial activation? Memory & Cognition, 20(6), 715-726.

Salthouse, T. A., & Mandell, A. R. (2013). Do age-related increases in tip-of-the-tongue experiences signify episodic memory impairments? Psychological Science, 24(12), 2489-2497.

Schwartz, B. L., & Frazier, L. D. (2005). Tip-of-the-tongue states and aging: Contrasting psycholinguistic and metacognitive perspectives. The Journal of General Psychology, 132(4), 377-391.

Answers!

Image: Monica Lewinsky

Q1: What is the name of the building where one can view projected images of celestial bodies on the inner surface of a dome? A planetarium.

Q2: What is the name of the large waterfall in Zambia that is one of the Seven Wonders of the World? Victoria Falls.