CHANGES IN COGNITION
RIGHT HEMISPHERE OF THE BRAIN
Controls muscles on the left hand side of your body, helps you see the bigger picture, understand emotions, recognise faces, weigh up options, pay attention to things on the left, and influences many other communication and thinking skills.
COGNITION AND THE RIGHT HEMISPHERE OF THE BRAIN
There are two sides (hemispheres) to the brain – the left and right. They are similar but not mirror images. The hemispheres are the same in the way each side controls the muscles on the opposite side of the body. How the sides differ relates to your thinking and communication.
When we communicate, we use both our left and right hemispheres of the brain. The left hemisphere manages our language or words and sentences, but it is the right hemisphere that decides when and how to use these building blocks of language. The right hemisphere allows you to interpret what needs to be said in a particular moment, and the best way to say it.
The right hemisphere of the brain also influences many cognitive or thinking skills. It is particularly important for us to evaluate different options. It also helps us to not only make sense of words that we hear but at the same time to pay attention to someone’s facial expressions, the way in which they are using their voices, and what we already know about them and the situation. If we have changes in our ability to pay attention to, remember and evaluate all these different ingredients of communication then we might not understand the whole picture of what is said.
This page provides brief summaries of some of the cognitive or thinking changes that might occur.
“Right until this meeting, I had no idea that there’s something unique about a right hemisphere stroke. They’re all unique, I understand that, but there’s obviously an important difference between it and other strokes.
There’s something different or special about right hemisphere stroke that’s worth investigating further. At no point did I see information that explained that this is the stroke I had and how it compared to if it was a left hemisphere stroke.“
70 year-old-man with right hemisphere stroke
There’s something different or special about right hemisphere stroke that’s worth investigating further. At no point did I see information that explained that this is the stroke I had and how it compared to if it was a left hemisphere stroke.“
70 year-old-man with right hemisphere stroke
COGNITION
Cognition refers to how our brain processes information, interprets the world, plans, and makes decisions. Its about how we think, take information in, and learn new things. To learn, understand and create meaning there are several different cognitive processes involved including attention, memory, problem-solving, and decision-making.
You use cognitive skills such as problem-solving and decision-making to make choices such as whether to drink a glass of water or orange juice, find your way in a new town, or play a game of chess.
Cognition is critical to navigating our everyday lives. It is also critical to help us communicate which is why we often find that people struggle with communication when their cognition has been changed after a stroke.
Every person who has a right hemisphere stroke is unique. Some people might experience only mild difficulties with cognition while others might notice changes in many types of thinking skills.
Executive functions – planning, problem solving, weighing options.
Attention – being able to pay attention even when there are distractions.
Social cognition – understanding what someone is thinking, feeling and intending to do next.
Self awareness – being aware of what has changed because of the stroke and how it impacts your communication.
Unilateral neglect – when the brain is not able to pay attention to what you see (unilateral spatial neglect) or hear (auditory neglect) on the left hand side of your body.
REDUCED SELF-AWARENESS
Reduced self-awareness, also called anosognosia, is a condition where individuals are less aware of the changes that came about because of their brain injury than what would be expected. A person may not fully recognise or understand the extent of their own difficulties, even when others can clearly see them. They might struggle to move their arm or forget to do something, but when asked about it, they genuinely believe that everything is fine, despite clear evidence to the contrary. Similarly, when asked if their communication has changed, they might deny any changes.
It is important to remember that the person is not choosing to ignore their difficulties and not lying on purpose when asked if anything is different since their stroke. Rather, the parts of the brain that normally help us to accurately evaluate how we are doing at tasks, and that help us to process information about ourselves and our bodies are damaged by the stroke.
Awareness of physical changes such as a weak arm, and difficulties with physical activities such as getting dressed, might improve in the weeks after a stroke. However, awareness of changes about things that are not as concrete or easy to see, such as managing emotions, understanding humor and planning an activity, might take longer to improve. It is often only when someone gets home after leaving hospital that they start to become aware of changes and how these changes influence returning to activities and their relationships.
Reduced self-awareness can be challenging for both the affected individual and their friends and family. For the person with anosognosia, it can lead to frustration about the activities that they cannot return to yet (such as driving) and a resistance to accepting help. Friends and family might not understand why someone is refusing help, and might not know how to help. It might take time, and supportive feedback to help someone with reduced awareness to gradually recognise their difficulties and for the brain to become better able at processing information again.
I think I think the speech pathologist was very good at explaining why we were doing things and what the outcome should be, but also saying, well how do you think you went?
We would talk about how I actually went, and try to bridge the gap to realising where I was really at.
66-YEAR-OLD MAN WITH RIGHT HEMISPHERE STROKE
He now needs more time to get organised with tasks and can get flustered especially when there is too much time pressure.
It was only when he returned to work that he realised that he was not as good at his job as what he was before the stroke, especially given the demands of his job.
WIFE OF A 49-YEAR-OLD MAN WITH RIGHT HEMISPHERE STROKE
EXECUTIVE FUNCTIONS
“Everything changed for him after the stroke. He could not return to work even if he wanted to. It was not because of physical changes. His thinking through problems completely changed.”
Wife of a 49-year old man with right hemisphere stroke
Executive functions is a term used to describe a number of cognitive skills that help us to set priorities, achieve goals, think flexibly, make decisions, and solve problems.
When we get started on a task, plan, organize, multi-task, pay attention to two things at once and stop ourselves from doing something impulsive, we are using our executive functions. These cognitive skills are important for us to succeed in tasks that are complex, new or unfamiliar, or in situations where we have to consider many things at once.
If you think of any complex activity such as submitting tax returns, choosing the perfect gift for a friend, or planning a workday, you start to see the important role that executive functions play. Executive functions can change after a right hemisphere stroke and be apparent from the person having trouble with tasks that they used to do with ease.
Some decisions that require weighing up options by thinking about pros and cons might not have major consequences on our lives. However, more often, changes in executive functions will create major challenges. As an example, many people who return to work after a right hemisphere stroke might have difficulty with getting started on tasks, solving problems, noticing and correcting errors and follow tasks through to completion.
Cognitive flexibility is another skill that is linked to the right hemisphere, which is the ability to switch between activities, points of view and think creatively by seeing many possible answers or solutions.
If you have experienced such difficulties then it might be because the stroke affected executive function skills. It is important for friends and family members to be aware of these changes and for you to work with healthcare professionals to set in place strategies to help you to adapt to new challenges, modify the environment, and to maximise your skills.
VISUAL AND AUDITORY NEGLECT
VISUAL
Visual neglect is common after a right hemisphere stroke, affecting 30% to 80% of people depending on the timing of being assessed.
Some people cannot process or pay attention to visual information on their left at all while others can ‘see items’, but only if they are made aware of it first and when there are no distractions in the room.
You might notice that someone has visual neglect if they bump into objects on their left when they walk, say that they cannot find an object that is in the left visual field, copy only the right hand side of a picture, or miss the first word or two when reading from left to right.
AUDITORY
Less is known about the number of people who have auditory neglect after a stroke. It is similar to visual neglect, however, this time the person might not notice sounds coming from the left despite having normal hearing.
On a practical level, this means that friends and family members should think about where they are standing or sitting when having a conversation as the person with a right hemisphere stroke might miss what is said if you are on their left.
It might also be difficult to localize sound which means that the person cannot easily say where a sound is coming from.
Visual and auditory neglect (also known as spatial or unilateral neglect) are conditions where the person with a right hemisphere stroke unintentionally ignore or fail to pay attention to one side of the world, even when nothing is wrong with vision or hearing.
Read more about how neglect may impact communication in the Communication Changes page.