What is acalculia, and why many stroke survivors struggle to get support with their number problems
What did the researchers aim to find out?
The study aim to identify evidence for available treatments for acalculia, by systematically searching the literature.
What type of research was done?
This was a systematic review
Results of the research
Acalculia is an acquired deficit in numerical skills, affecting between 30%−60% of brain-injury survivors. It impacts every day tasks such as managing money, and taking correct medication. Because of this, it impacts the independence and wellbeing of those who are affected.
In this study, we systematical searched the literature to identify studies that describe interventions for acalculia. We included any study that was:
1. published in English before June 2025
2. involved an intervention for acalculia that directly address numerical skills
3. reported intervention outcomes.
We assessed the studies’ quality using the Quality Assessment with Diverse Studies (QuADS) tool.
Only 16 publications involving 31 participants were identified. We also found one app-based intervention with 18 patients, but this was not published in a journal, but was available online.
Ten of the 26 interventions targeted relearning of multiplication tables, and four interventions were for improving transcoding (transferring between written and spoken numbers). All interventions were delivered individually (there were no group interventions) and almost all the interventions were tailored to individual patients.
The most common delivery method was intense repetition (“drill”), and most interventions were conducted in French or German. Only one intervention was delivered in non-European language (Japanese). This is despite evidence that there are linguistic and cultural effects on numerical skills.
The findings highlight how little evidence there is for acalculia interventions, which explains why patients find it hard to get support. In the discussion we explore suggestions for future interventions.
We conclude that there is an urgent need to improve provisions for patients and to support clinicians so that they can better support patients.
Why was the research done?
the research was conducted because in our previous work, we found that patients say they can not get support for their acalculia. We also noticed that there are no systematic reviews that are up to date about any available interventions.
What does the research mean for me and others?
It may be that you have acalculia- but you do not realise it, because no one tested you or told you this. you may not even know that the problems you have with numbers have a name. Acalculia can occur with or without Aphasia.
We hope that this work can increase awareness to the condition. We also hope it will encourage researchers to develop interventions. If you do experience these problems, you may find this article interesting, and it has some basic suggestions on what have been done to date to support patients.
What research methods were used?
In this work, we systematically searched the literature, and summarised all the evidence we found. We also combined this with current theoretical framework, to suggest where interventions should go in the future.
How to obtain the treatment detailed in the research?
The article summarise the treatments used in the different publication, but to get details on these, you may have to go directly to the articles we summarised.
Background information on the research topic
Numbers are all around us. In the morning, we wake up to an alarm that tells us it’s time to get out of bed. When deciding what to wear, we often check the temperature outside. We count out the vitamins or prescription pills we need to take while eating our breakfast, we estimate how long it will take to get to the station and then check what platform we need to be on catch the train to work.
Every single one of these examples involves using and understanding numbers. Being able to carry out such small calculations and estimations makes our life possible.
This is why acalculia, a neurological condition that impairs the ability to process and understand numbers, can have a devastating effect on a person’s life.
Acalculia is not taught in most clinical training at present. One patient we interviewed in our previous study recalled asking their therapists for help with acalculia, saying: “What can you do to help me with my maths?" Every therapist they met sayid ‘I can’t help you’. "Why? Because it’s not part of their training.”
This means healthcare workers are not able to recognise the problem – let alone be able to support patients who have it.
People with acalculia are currently left to support themselves. Many may not even know there’s a name for their condition. It’s clear more needs to be done to raise awareness so that it can be better assessed – and so patients can receive the help and support they need in overcoming acalculia.
Risks related to the research
We do not think there are any risks associated with this work
Who was allowed to take part in the research?
Not applicable
Information about the people who took part
The work did not involve human participants
Why was the research done this way?
We decided to collect literature in English because we had no resources to translate non-English work. However, we found three publications, which we do mention, that cover work that was published in other languages.
When was the research done?
the research took place between June 2024 and December 2025
Where was the research done?
In Manchester Metropolitan University, UK.
Where did the money come from?
We did not receive funding for this work.
Problems with the research
there are several limitations to the work:
1. we only reviewed articles published in English
2. we only reviewed intervention for acallculia that resulted from stroke or brain injury- we found one or two studies that covered intervention for dementia, but we did not report these, because we believe it is a different case
Is the research trustworthy?
The work has been published in a good journal, after being peer reviewed, so we believe it is trustworthy
Next steps
It is important that these findings are used to:
1. increase awareness to Acalculia and to the lack of treatment
2. encourage researchers to try new interventions, and test them in clinical settings
Where to find information related to the research?
You can find the related publication on the experience of people with acalculia here: https://www.tandfonline.com/doi/full/10.1080/09602011.2022.2108065
You can also find an article for the public about the condition here: https://theconversation.com/acalculia-why-many-stroke-survivors-struggle-with-numbers-265643
You may also contact the main author (Yael Benn)
