ABSTRACT :
The podcast we are offering today is a fictional interview between Muriel Vandenberghe, Phd in Psychology Sciences Department in University of Brussels and a journalist. Muriel is one of the researchers who developed a neuropsychological test called the Geria-12. The journalist would like to know more about this cognitive test. He asks Muriel several questions. He wonders what the purpose of the Geria-12 is, why these researchers developed it, what deficits can be encountered in a neurodegenerative disease such as Alzheimer’s, since this test is aimed more specifically at this population. But also what is the difference with the RL-RI16, which is a very well known and widely used cognitive test, and which is very similar to Geria-12, both in the way it is administered and in its results. The journalist also asks for details about the Geria-12 pass, its norms and limitations. Finally, the journalist is going to ask Muriel to give him a concrete example, a case study, with results from Geria-12 that might suspect Alzheimer’s disease.
We have chosen to make a podcast about this cognitive test, as it is not yet widely used by neuropsychologists, preferring the RL-RI16. However, this test is free of charge, and is exclusively aimed at the elderly. It is therefore an interesting test, but still unknown. Due to containment, we can not record the entire podcast as an audio file.
QUESTIONS :
- Welcome, introduce yourself. Who are the searchers who have collaborated ?
I’m Muriel Vandenberghe, Phd in Psychology Sciences Department in University of Brussels. I work on learning and memory, cognitive neuroscience, gerontology, AD, cognitive and clinical Neuropsychology, cognition disorders, and neuropsychological Assessment.
Me and my group of belgian searchers composed by Michiels, Vanderaspoilden, Claes et Fery worked together to propose a new tool : the GERIA-12. It’s a cognitive test which assesses verbal episodic memory in the elderly aged from 70 to 89 years old, and coming from different socio-cultural environments.
2. Why create the GERIA-12 ? What was the purpose ?
Our objectives in the creation of this test were to :
- create a new assessment task of encoding, consolidation and retrieval in episodic memory by proposing a process adapted to the elderly, which isn’t the case in the RL/RI 16.
- establish specific norms on age range beyond 70 years old.
- assess people with a potential AD, because this population is known to suffer from a early dysfunction of episodic memory.
- offers a free access online on our website, and by doing so removing the barrier of money to use it in a clinical purpose.
3. Tell us about the difficulties that can be observed in AD.
AD is characterized by an episodic memory dysfunction. The episodic memory is the memory of specific events belonging to a clear spatio-temporal context, and associated with vividness and a mental journey through subjective time. AD subjects in RL/RI 16 or GERIA-12 are characterized by less benefit from semantic cue (encoding issue) and more difficulties in delayed recall (consolidation issue), whereas in normal aging, semantic cue is efficient and we observe a stability of delayed recall.
4. What does this test evaluate ?
This test enables to calculate 3 types of indications :
- Encoding indication, which is the number of non encoded items (non presents in the free and delayed recalls), tells us about potential encoding difficulties of the patient : the higher the indication, the more severe is the encoding difficulty. Indeed, as we said before, AD patients are characterized by an encoding failure. In the normal population, this indication is close to zero.
- Consolidation indication is the number of items not present in the delayed free recall nor in the delayed cued recall, but present at each learning trial. It tells us about potential consolidation difficulties of the patient, which again, might help us identify patients with AD, because they often have a consolidation deficit. The lowest the indication, the higher the consolidation difficulty.
- Finally, retrieval indication is the number of items retrieved in the different steps of cued recall compared to the number of cues that were provided. It helps us identify an eventual effect of cues on retrieval, which is generally not efficient in AD. The lowest the indication, the highest the retrieval difficulty. In the normal population, this indication is generally very high.
5. What is the difference with the RL-RI16 ?
Our test is close to, and inspired by the RL-RI16. Indeed, it allows us to evaluate the different encoding, storage, consolidation and retrieval processes in episodic verbal memory. However, it has some notable differences and several adaptations, as it is addressed to an elderly population only. It is therefore an abridged version, with 12 items to be retained rather than 16 items. We also preferred to set up two learning tests rather than three, in order to alleviate possible fatigue in these subjects. In fact, we had observed in another study that the third test phase did not necessarily provide any additional information. Then, we chose to add a deferred recall 24 hours after the test to have a better idea of the subject’s consolidation. In addition, in the quotation, we decided to include threshold values for intrusion and perseveration. This type of error is often found in patients with neurodegenerative diseases such as Alzheimer’s disease. It is therefore interesting to have these values. We therefore believe that with these slight modifications, the calculation of the indices allows a better apprehension of the memory processes.
6. How does a neuropsychological assessment with GERIA-12 work ?
First of all, we present twelve words on the subject, each of which belongs to a category, for example the mandarin, which is a fruit, or the trumpet, which is a musical instrument. We ask the subject to remember these words and then proceed to an immediate recall to check the encoding capabilities. Next, a distracting task is proposed (a countdown). Following this task, we ask the subject to recall as many words as he or she can remember from the list, this is the first free recall. If he cannot find it, we give the category of the object as a clue. If he still doesn’t find it, we give him feedback. Then another distracting task is proposed. Then a second free recall, this time without feedback. We then let the subject do other cognitive tasks (rather visual so as not to disturb the auditivo-verbal memory), and 20 minutes later we propose a last free recall. Finally, we wait 24 hours, then call the patient at home to ask him/her which words from the list come back to his/her memory. This then allows us to evaluate their storage, consolidation and retrieval capacities. The quotation is done using an Excel table available free of charge on our website. The principle is very similar to the RL-RI16, with the few adjustments mentioned in the previous question.
7. What are the norms of this test ?
The special feature of this test is that it is standardised according to three criteria. Firstly, age, divided into two groups with a population of subjects aged between 70 and 79, and another between 80 and 89. Secondly, the level of education in 3 distinct school levels. Finally, gender, male or female. We decided to take these three factors into account because they have an impact on some aspects of episodic memory.
8. What are the limits that can be found ?
Although this test has been reviewed in order to better assess the verbal episodic memory of elderly subjects, we have indeed noted some limitations. Firstly, the test ends at the age of 89, whereas in the RL-RI16 the age limit is 88. Subjects aged 90 or over are therefore still without norms at present. Moreover, it is true that our two free recall learning programmes do not necessarily show a learning curve as is the case with RL-RI16. We also give only one feedback at the first free and indexed recall. This is a choice on our part, but sometimes this choice can also affect the results. Finally, we have decided to add a 24-hour free recall after learning. This is an initiative that we took in order to best evaluate the consolidation, but we noticed that sometimes the difference in context between the learning and the feedback could also impact the results.
9. Can you give us a concrete example, a “false case study” that can be diagnosed with your test ?
Let’s imagine a 75 year elderly who uses the Geria-12 in a neuropsychological check-up, a memory consultation for example. In the results, we find an immediate recall (therefore encoding) at 12/12. The first free recall is 3, therefore deficient. The second free recall is also 4 and deficient. The recognition is 11/12. The free recall delayed by 20 minutes is 3/12, and the free recall delayed by 24 hours is 2/12. Moreover, the indication does not make it possible to standardize the results for each of the recalls. In addition to this, we observe 3 intrusions during the test. These results suggest a correct encoding and retrieval, but a deficit in terms of storage and consolidation. We know that people suspected of Alzheimer’s disease have large deficits in these two areas. Intrusions are also an alarming sign. Finally, results of this kind could be an incentive for further investigation in the direction of Alzheimer’s disease.
Thank you very much !
Fiona Lami & Alice Mercier