Memory Research News in Aging

Older adults' distractability can be used to help put a face to a name

  • A small study has used older adults’ inability to ignore irrelevant information to improve their memory for face-name pairs.

One important reason for the greater cognitive problems commonly experienced as we age, is our increasing difficulty in ignoring distracting and irrelevant information. But it may be that in some circumstances that propensity can be used to help memory.

The study involved 25 younger (17-23) and 32 older adults (60-86), who were shown the faces and names of 24 different people and told to learn them. The names were written in bright blue text and placed on the forehead, and each photo was shown for 3 seconds. After the learning session, participants were immediately tested on their recall of the name for each face. The test was self-paced. Following a 10 minute interval, during which they were given psychological tests, they were shown more photos of faces, but this time were told to ignore the text — their task was to push a button when they saw the same face appear twice in a row. The text was varied: sometimes names, sometimes words, and sometimes nonwords. Ten of the same faces and names from the first task were repeated in the series of 108 trials; all items were repeated three times (thus, 30 repeated face-name pairs; 30 other face-name pairs; 24 face-word pairs; 24 face-nonword pairs). The photos were each displayed for 1.5 seconds. A delayed memory test was given after another 10 minutes of psychological testing. A cued-recall test was followed by a forced-choice recognition test.

Unsurprisingly, overall younger adults remembered more names than older adults, and both groups remembered more on the second series, with younger adults improving more. But younger adults showed no benefit for the repeated face-name pairs, while — on the delayed recall task only — older adults did.

Interestingly, there was no sign, in either group, of repeated names being falsely recalled or recognized. Nor did they significantly affect familiarity.

It seems that this sort of inadvertent repetition doesn’t improve memory for items (faces, names), but, specifically, the face-name associations. The study builds on previous research indicating that older adults hyperbind distracting names and attended faces, which produces better learning of these face-name pairs.

It’s suggested that repetition as distraction might act as a sort of covert retrieval practice that relies on a nonconscious process specifically related to the priming of relational associations. Perhaps older adults’ vulnerability to distraction is not simply a sign of degeneration, but reflects a change of strategy to one that increases receptiveness to environmental regularities that have predictive value. Younger adults have narrowed attention that, while it allows them greater focus on the task, also stops them noticing information that is immediately irrelevant but helpful further down the track.

The researchers are working on a training program to help older adults with MCI use this benefit to better remember faces and names.

https://www.eurekalert.org/pub_releases/2018-03/bcfg-oad031618.php

Reference: 

Biss, Renée K., Rowe, Gillian, Weeks, Jennifer C., Hasher, Lynn, Murphy, Kelly J. 2018. Leveraging older adults’ susceptibility to distraction to improve memory for face-name associations. Psychology and Aging, 33(1), 158-164.

Gist memory may be why false memories are more common in older adults

  • Gist processing appears to play a strong role in false memories.
  • Older adults rely on gist memory more.
  • Older adults find it harder to recall specific sensory details that would help confirm whether a memory is true.

Do older adults forget as much as they think, or is it rather that they ‘misremember’?

A small study adds to evidence that gist memory plays an important role in false memories at any age, but older adults are more susceptible to misremembering because of their greater use of gist memory.

Gist memory is about remembering the broad story, not the details. We use schemas a lot. Schemas are concepts we build over time for events and experiences, in order to relieve the cognitive load. They allow us to respond and process faster. We build schemas for such things as going to the dentist, going to a restaurant, attending a lecture, and so on. Schemas are very useful, reminding us what to expect and what to do in situations we have experienced before. But they are also responsible for errors of perception and memory — we see and remember what we expect to see.

As we get older, we do of course build up more and firmer schemas, making it harder to really see with fresh eyes. Which means it’s harder for us to notice the details, and easier for us to misremember what we saw.

A small study involving 20 older adults (mean age 75) had participants look at 26 different pictures of common scenes (such as a farmyard, a bathroom) for about 10 seconds, and asked them to remember as much as they could about the scenes. Later, they were shown 300 pictures of objects that were either in the scene, related to the scene (but not actually in the scene), or not commonly associated to the scene, and were required to say whether or not the objects were in the picture. Brain activity was monitored during these tests. Performance was also compared with that produced in a previous identical study, involving 22 young adults (mean age 23).

As expected and as is typical, there was a higher hit rate for schematic items and a higher rate of false memories for schematically related lures (items that belong to the schema but didn’t appear in the picture). True memories activated the typical retrieval network (medial prefrontal cortex, hippocampus/parahippocampal gyrus, inferior parietal lobe, right middle temporal gyrus, and left fusiform gyrus).

Activity in some of these regions (frontal-parietal regions, left hippocampus, right MTG, and left fusiform) distinguished hits from false alarms, supporting the idea that it’s more demanding to retrieve true memories than illusory ones. This contrasts with younger adults who in this and previous research have displayed the opposite pattern. The finding is consistent, however, with the theory that older adults tend to engage frontal resources at an earlier level of difficulty.

Older adults also displayed greater activation in the medial prefrontal cortex for both schematic and non-schematic hits than young adults did.

While true memories activated the typical retrieval network, and there were different patterns of activity for schematic vs non-schematic hits, there was no distinctive pattern of activity for retrieving false memories. However, there was increased activity in the middle frontal gyrus, middle temporal gyrus, and hippocampus/parahippocampal gyrus as a function of the rate of false memories.

Imaging also revealed that, like younger adults, older adults also engage the ventromedial prefrontal cortex when retrieving schematic information, and that they do so to a greater extent. Activation patterns also support the role of the mediotemporal lobe (MTL), and the posterior hippocampus/parahippocampal gyrus in particular, in determining true memories from false. Note that schematic information is not part of this region’s concern, and there was no consistent difference in activation in this region for schematic vs non-schematic hits. But older adults showed this shift within the hippocampus, with much of the activity moving to a more posterior region.

Sensory details are also important for distinguishing between true and false memories, but, apart from activity in the left fusiform gyrus, older adults — unlike younger adults — did not show any differential activation in the occipital cortex. This finding is consistent with previous research, and supports the conclusion that older adults don’t experience the recapitulation of sensory details in the same way that younger adults do. This, of course, adds to the difficulty they have in distinguishing true and false memories.

Older adults also showed differential activation of the right MTG, involved in gist processing, for true memories. Again, this is not found in younger adults, and supports the idea that older adults depend more on schematic gist information to assess whether a memory is true.

However, in older adults, increased activation of both the MTL and the MTG is seen as rates of false alarms increase, indicating that both gist and episodic memory contribute to their false memories. This is also in line with previous research, suggesting that memories of specific events and details can (incorrectly) provide support for false memories that are consistent with such events.

Older adults, unlike young adults, failed to show differential activity in the retrieval network for targets and lures (items that fit in with the schema, but were not in fact present in the image).

What does all this mean? Here’s what’s important:

  • older adults tend to use schema information more when trying to remember
  • older adults find it harder to recall specific sensory details that would help confirm a memory’s veracity
  • at all ages, gist processing appears to play a strong role in false memories
  • memory of specific (true) details can be used to endorse related (but false) details.

What can you do about any of this? One approach would be to make an effort to recall specific sensory details of an event rather than relying on the easier generic event that comes to mind first. So, for example, if you’re asked to go to the store to pick up orange juice, tomatoes and muesli, you might end up with more familiar items — a sort of default position, as it were, because you can’t quite remember what you were asked. If you make an effort to remember the occasion of being told — where you were, how the other person looked, what time of day it was, other things you talked about, etc — you might be able to bring the actual items to mind. A lot of the time, we simply don’t make the effort, because we don’t think we can remember.

https://www.eurekalert.org/pub_releases/2018-03/ps-fdg032118.php

Reference: 

[4331] Webb CE, Dennis NA. Differentiating True and False Schematic Memories in Older Adults. The Journals of Gerontology: Series B [Internet]. Submitted . Available from: https://academic.oup.com/psychsocgerontology/advance-article/doi/10.1093/geronb/gby011/4840027

Lifestyle changes can prevent cognitive decline even in genetically at-risk individuals

  • A large study indicates that lifestyle changes, together with advice and support for managing vascular health, can help prevent cognitive decline even in carriers of the Alzheimer's gene.

A Finnish study involving over 1000 older adults suggests that a counselling program can prevent cognitive decline even among those with the Alzheimer’s gene.

The study involved 1,109 older adults (aged 60-77) of whom 362 were carriers of the APOE4 gene. Some of the participants received regular lifestyle counselling (general health advice), while the rest received “enhanced” lifestyle counselling, involving nutrition counselling, physical and cognitive exercises, and support in managing the risk of cardiovascular diseases.

Earlier findings from the FINGER (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability) trial showed that the regular lifestyle counselling group had a significantly increased risk of cognitive and functional impairment compared to the group receiving enhanced counselling. This analysis shows that this holds true even for those with the Alzheimer's gene, and indeed, might even be more helpful for carriers of the risky gene.

The findings emphasize the importance of early prevention strategies that target multiple modifiable risk factors simultaneously.

https://www.eurekalert.org/pub_releases/2018-01/uoef-lcp012518.php

Reference: 

[4330] Solomon A, Turunen H, Ngandu T, Peltonen M, Levälahti E, Helisalmi S, Antikainen R, Bäckman L, Hänninen T, Jula A, et al. Effect of the Apolipoprotein E Genotype on Cognitive Change During a Multidomain Lifestyle Intervention: A Subgroup Analysis of a Randomized Clinical Trial. JAMA Neurology [Internet]. 2018 ;75(4):462 - 470. Available from: https://jamanetwork.com/journals/jamaneurology/fullarticle/2670443