A new study discovered that implicit learning (learning something without realizing it) might benefit stroke patients who suffer from a neurological dysfunction known as neglect. Neglect is when someone loses the ability to pay attention to things happening on a particular side of their body.
Any person who suffers from neglect is unable to detect motions or events happening on the affected side. Besides this loss in detection, they also lose the ability to move in response to stimuli on the affected side. Unfortunately, neglect is very difficult to treat since most patients don’t notice that they have this problem.
Implicit learning exercises helping with neglect
Researchers from Belgium recently conducted a study to investigate the role of learning exercises in stroke rehabilitation, and specifically, the effect on neglect. They focused on implicit learning. This method is a type of unconscious learning where you aren’t aware of the fact that you are learning something. It is how babies learn to speak, and children progress with language. By merely hearing or seeing something over and over again, the mind picks up on patterns and meanings. Previous research has indicated that these subconscious types of learning processes may help improve attention in patients who suffer from neglect.
Researchers recruited ten patients with neglect. The patients ranged in ages from 44 to 79. All had experienced a stroke anywhere from 1 month to more than 2.5 years ago. Subjects, as well as healthy controls, were trained with implicit learning exercises in the form of a letter-based task. Letters appeared on either side of a box on a computer screen. Study participants had to read the letter they saw out loud and hit a key on a keyboard to indicate whether the letter was on the right or left side of the screen. All subjects performed this task with 4 different sets of letters, with 105 trials per set.
The task might seem simple enough, but researchers kept something from the participants. There was a pattern to the positioning of some of the letters. Some things were predictable if you knew what to look for. Half of the letters were based on the previous one, while the other half was truly random. The researchers wanted to see if the participants started to recognize the pattern where there was one. In other words, learn the pattern implicitly, without knowing they were learning it.
Healthy participants were able to improve their task performance for predictive letters. However, patients with neglect did not improve significantly. For those patients, task performance was drastically worse when the letters on the screen appeared on their affected side, which wasn’t surprising.
During their study, something unexpected happened though. One of the stroke patients managed to outperform even the healthy subjects in completing this task when the letters appeared on his non-affected side. Researchers hypothesize that the use of this implicit learning exercise can improve the attention and memory of participants who suffered a stroke. Although the performance improvement in neglect patients was not as significant as in healthy participants, researchers still feel it is worth looking into. It could be that patients with neglect need more sets and more time before performance improves.
Because neglect in stroke patients is so challenging to treat, the potential benefit of implicit learning as part of stroke rehabilitation should not be taken lightly. The researchers feel that stroke patients could benefit from these exercises. They think patients would especially benefit when they engage in these tasks over a more extended period. Everyone’s learning curve is different, so it’s likely that a longer training period will yield better results.
Talk to your doctor or therapist if there are implicit learning exercises that you can try.
The lead author of this publication is Murielle Wansard from the Department of Psychology, Cognition and Behavior, Neuropsychology Unit, University of Liège, Belgium.