From tennis to language learning – ScienceDaily
Variability is critically important for learning new skills. Consider learning to serve in tennis. Should you always practice serving from exactly the same spot on the court, aiming for the exact same spot? Although training in more variable conditions will be slower in the beginning, it will likely make you a better tennis player in the end. Indeed, variability leads to a better generalization of what is learned.
Chihuahuas and Great Danes
This principle is found in many areas, including speech perception, grammar, and the learning of words and categories. For example, infants will have a hard time learning the “dog” category if they are only exposed to Chihuahuas, instead of many different types of dogs (Chihuahuas, Poodles, and Great Danes).
“There are more than ten different names for this basic principle!” says Limor Raviv of MPI, lead researcher of the study. “Learning from less variable inputs is often rapid, but may not generalize to new stimuli. But this important information has not been unified into a single theoretical framework, which has clouded the picture of whole.
To identify key patterns and understand the underlying principles of variability effects, Raviv and his colleagues reviewed more than 150 studies of variability and generalization in all fields, including computer science, linguistics, categorization, l motor learning, visual perception and formal education.
The researchers found that, across studies, the term variability can refer to at least four kinds variability, like set size (e.g. the number of different examples or locations on the tennis court) and Planning (e.g. training times with different orders or time differences). “These four types of variability have never been directly compared, which means we currently don’t know which is more efficient for learning,” Raviv says.
The impact of variability varies depending on whether it is relevant to the task or not (it can be said that the color of the tennis court is not relevant for service training). But according to the ‘M. Miyagi’s principle (inspired by the classic 1984 film Karate Kid), practicing seemingly unrelated skills (like waxing cars) can actually benefit learning other skills (like martial arts).
But Why does variability impact learning and generalization? One theory is that more variable input can highlight which aspects of a task are relevant and which are not (color is useful for distinguishing between lemons and limes, but not for distinction between cars and trucks).
Another theory is that greater variability leads to broader generalizations. This is because variability will better represent the real world, including atypical examples (like Chihuahuas).
A third reason has to do with how memory works: when learning is variable, learners are forced to actively reconstruct their memories.
“Understanding the impact of variability is important to literally every aspect of our daily lives. In addition to affecting how we learn language, motor skills and categories, it even impacts our social lives,” says Raviv. “For example, facial recognition is affected by whether people grew up in a small community (less than 1,000 people) or in a larger community (more than 30,000 people). Exposure to fewer faces during childhood is associated with decreased facial memory.
“We hope this work will pique people’s curiosity and generate more work on the topic,” Raviv concludes. “Our article raises many open questions. For example: Is the relationship between variability and learning broadly similar across species, or are there species-specific adaptations? Can we find similar effects of variability beyond the brain, for example in the immune system? »