A new study has found working memory as a cause of learning difficulties in people with schizophrenia. Working memory is known to be affected in 1% of the population who have schizophrenia, however, it has been unclear whether that has a specific role in making learning more difficult, said lead author Anne Collins. Researchers measured the effects of working memory and reinforcement in learning and found that only working memory was a source of impairment. “We really tend to think of learning as a unitary, single process, but really it is not,” said Collins, who with fellow researchers, developed an experimental task and a computational model of cognition that can distinguish the contributions of working memory and reinforcement in the learning process. “We thought we could try to disentangle that here and see if the impairment was in both aspects, or only one of them.”
For the study, the researchers compared 49 schizophrenia patients to 36 patients without the condition. The participants were shown a set of images and then were asked to push one of three buttons when they saw each image. They were told each time whether they had hit the correct button for that image. The researchers found that there was no difference between the groups in reinforcement learning. According to the researchers, the findings supported their hypothesis that working memory alone damages learning in people with schizophrenia. However, no associations were found between reinforcement and learning impairments in schizophrenia patients. Additionally, the study showed that targeting reinforcement is more favorable in improving the ability to learn in people with schizophrenia.
“More broadly it brings attention to the fact that we need to consider learning as a multifactor kind of behavior that can’t be just summarized by a single system,” Collins said. “It’s important to design tasks that can separate them out so we can extract different sources of variance and correctly match them to different neural systems.”