The dementia of the Alzheimer type is the most common type of dementia in the world, and is characterised typically in the earliest stages by problems in short term learning and memory. A prominent message relating to the notion that it is possible to live well with dementia is that, with careful attention, a person living with dementia might be able to focus on what he or she can do, rather than what he or she has difficulty with. Of course, trying to persevere at anything which is difficult can be inherently demoralising for the best of us. That’s why to put a person living with dementia of the Alzheimer type, where very old memories can be very well preserved compared to a memory for what was done yesterday, at ease, it is easier to engage in conversation about things way in the past.
Declarative memory is recall of factual information such as dates, words, faces, events, and concepts. Remembering the capital of France, involves declarative memory. Declarative memory is usually considered to be explicit because it involves conscious, intentional remembering. Procedural memory is recall of how to do things such as riding a bike.
Declarative memory is of two types: semantic and episodic. Semantic memory is recall of general facts, while episodic memory is recall of personal facts. Remembering the capital of France and the rules for playing football uses semantic memory. Remembering what happened in the each game of the World Series 2014 uses episodic memory, for example. Declarative memory can be emotional or non-emotional.
The bookcase analogy is well known to anyone who’s done ‘Dementia Friends’.
Here is the explanation openly searchable on YouTube.
While there is more to a person living with dementia than the clinical diagnosis, the clinical diagnosis – if correct – does give very good clues normally as to which parts of a distributed neuronal network might be affected early on in disease. Whilst most attention has been given to pharmacological interventions, there is increasing recognition that psychosocial interventions may have comparable value, and may be preferable in some contexts, e.g. where medication may be ineffective or have negative side-effects.
Anecdotal and empirical evidence suggests that emotionally important events hold a special place in memory, where they are bestowed with a unique subjective vivid character. The successful retrieval of information from long-term memory requires the integrated activity of multiple brain regions. And the information does not only come from post mortem studies.
“Sporting Memories Network” was established to promote and develop the use of sporting memories to improve the wellbeing of people through conversation and reminiscence.
“Bill’s Story” is a good introductory film to this unique initiative, only lasting a few minutes. Little was known about Bill Corbett’s sporting prowess as a fine footballer playing for Celtic. It became known through participation in the memory group that his personal history included playing for Scotland. So he became ‘unlocked’ as a person.
A diagram of how the brain might approach a ‘football memory’ is shown below.
The cognitive and behavioural processes involved in reactivating a football memory are especially interesting, given what we know about their putative neural substrates. Reacting a ‘football memory’ is indeed a brilliant example of taking advantage of what a person living with dementia can do, rather than what he or she cannot do.
Some time last century, an amazing advance in the cognitive neurology of memory was made. In 1957, William Scoville and Brenda Milner published the now famous case of patient H.M. Scoville surgically removed large parts of the medial temporal lobe (MTL; including the bilateral hippocampi) in H.M., to relieve him from intractable epilepsy. This is the part of the brain quite close to the ear. The surgery was successful in controlling his epilepsy, however, it also elucidated that the hippocampus is essential for the formation of new memory traces. H.M. was severely impaired in learning episodic information and facts (declarative/explicit memory), although the formation of non-declarative (implicit) memory such as procedural memory was not disrupted.
Early theories proposed to explain the neuropsychological basis of emotion perception (Cannon 1929; James 1884) emphasised the importance of feedback from bodily responses to an emotionally salient stimulus in determining the nature and extent of emotional feeling, but they did not distinguish between the identification of the emotive stimulus and the affective state produced in response to this.
But not all memories are the same. In dementia of the Alzheimer type, as I have already described, older memories can be quite well preserved compared to the memory from yesterday. In humans, damage limited to the hippocampus produces temporally graded retrograde amnesia, with relative sparing of remote compared to recent memory. This observation forms the cornerstone of the idea that as memories mature they are reorganised in a time-dependent manner. In the late part of the 19th century, the French psychologist, Theodule Ribot, described how memory loss after brain insult was often related to the age of the memory: the effect on more recent memories was typically greater than that on older (or more remote) memories.
This observation forms the basis of the idea that memories are reorganised in a time-dependent manner. Within this general framework, the relative contributions of different brain regions may vary as a function of memory age. Accordingly, some regions may play important roles in the expression of newly formed (or recent) memory, but their contributions may fade over time. Conversely, other regions may play preferential roles in the expression of older (or remote) memories.
What happens when you get confronted by ‘football memories’?
Memories of events evoking strong emotions, especially fear, selectively persist because emotion enhances event-memory retention. The hippocampus is crucial in processing declarative and spatial long-term memory, whereas the amygdala drives emotion processing and emotional memory formation.
Whether or not emotion enhances event memory retention is controversial. By using photographs with affective valence as both encoding and recall stimuli, some authors found that emotion accelerates episodic memory encoding. However, others speculate that emotion simply heightens the subjective sense of remembering, and that increase in the subjective ratings of vividness, recollection, and belief in accuracy does not indicate accurate memory.
Overall, it appears that emotion can enhance memory accuracy, particularly for the fact that an event occurred, but emotion’s impact on the sense of the vivid recollection of details exceeds its influence on memory for those details per se. In other words, emotion boosts memory accuracy to an extent, but it affects the subjective sense of recollection even more.
The vital thing to note is that these memories are not divorced from us as people. They are intimately tagged in the timeline of our past. Autobiographical memories (ABM) of past experiences can be often elicited spontaneously; something we encounter in our environment or in our thoughts directly transports us back in time to mentally re-experience that one particular event.
But was it a happy match? Or was it the worst match of your life?
Gist is an interesting concept.
“Gist” can be defined as the global (overall) emotionality, whereby the scene can be rapidly identified as positive, negative, or neutral without having to explore the individual (local) features of the scene. To take as an example, a picture of the aftermath of the “Twin Towers scene” would hold a negative gist, whereby every scene feature would be negative and related to the overall “story,” e.g., buildings being demolished, aeroplanes crashing—there is not just one negative feature but an overall negative emotional valence. It is also possible that aversive, and potentially dangerous, stimuli, are processed as more immediately salient for survival than positive stimuli that usually signal feeding, procreative, or social opportunities.
The special nature of faces
Cognitive psychologists have been interested in this phenomenon because there is evidence that faces are somehow perceived differently than other patterned objects, and thus, may represent a ‘special’ class of stimuli.
In the human lesion literature, the recognition and identification of famous faces has commonly been used to study the neural regions critical for retrieval of information from long-term memory. It is generally acknowledged that famous faces produce automatic retrieval of person-identity information from long-term memory
“The smell of Bovril”
Visual memories do not operate in isolation.
One of the most profound questions for neuroscientists of all interests is why the human brain has exploded relatively in size, compared to its counterpart in the animal kingdom. Prof Horace Barlow, a previous chair in physiology at Cambridge, thought this was fundamental for example why the visual part of our brain – the visual cortex – was so substantially different to the film of the eye recording images in the fly’s retina.
“I am not the only one for whom many of life’s most intimate details come flooding back at the sight, smell and taste of particular foods. Everyone I speak to seems to have a favourite or, in some cases, a most hated dish with which they can recall particular moments of their lives.”
I have just provided examples of innovative approaches from art, music and “football memories” which comprise an alternative to pharmacological treatments for dementia. This is an important thrust of my thesis. Enhancing wellbeing through such priorities must be a legitimate aim of dementia friendly communities, and we are in desperate need of high quality research with the aspiration of living better with dementia.
[I gave a cognitive neurology explanation of ‘sporting memories’ in chapter 15 of my book ‘Living better with dementia: good practice and innovation for the future’ (Explaining the Triggering of Sporting Memories in People Living Better with Dementia) published by Jessica Kingsley Publishers (2014).
This was the first description of this in the world to my knowledge.]