23 How many languages are there? Johann Wolfgang von Goethe said: As many languages you know, as many times you are a human being. Roger Bacon wrote: Knowledge of languages is the doorway to wisdom . Both the visual and the auditory cortex are part of the cerebral cortex. Where are the Broca and Wernicke areas located in the brain? 43% of the world s population is bilingual, according to the Journal of Neurolinguistics. Almost half of all people use two languages daily. 17% of the world s population is multilingual. LANGUAGE Language is a form of communication, a living creature which represents culture, customs, thoughts, faith, and emotions and that changes every day, adapting to the needs of its users. It plays a central role in the human brain: it directs how we interpret colour, create moral values, understand and remember events, classify objects and smells, stay oriented, reason about time, perform mental mathematics, make decisions, experience and express emotions, and so on. Effects of language Experience with language modifies the brain, changing its neural connectivity: the number of languages a person speaks, the age these languages were learned, the structures and patterns of the languages they speak, the way the languages are experienced (for example spoken vs read), and even the way the languages are written (for example left-to-right or rightto-left) affect cognitive abilities and how people imagine and organise information. The language we use changes the way we think and express ourselves and how we perceive and interact with the world. Language and the brain In around 97% of people, it is the left hemisphere of the brain which is responsible for language and speech and, for this reason, this is called the to discern: distinguere intelligibly: in maniera comprensibile thickness: spessore to tuck away: mettere via wisdom: saggezza 52 BODY AND MIND dominant hemisphere. However, in about 19% of people who are left-handed, speech function may be located in the right half of the brain. Language brain regions There are four main areas of the brain involved with language: the visual cortex is responsible for processing visual information; the auditory cortex processes information coming from sound; the Broca area is in charge of moving the tongue and facial muscles to produce the sounds of speech, making it possible to not only speak, but also write, intelligibly; the Wernicke area allows language to be understood. Bilingualism According to recent studies, the more languages we learn, especially during childhood, the easier our brain finds it to process and retain new information. Apparently, language-learning, and bilingualism in particular, boosts brain cells potential to form new connections fast. Moreover, speaking two languages: develops the temporal lobes of the brain, which have a key role in forming new memories; increases the thickness and density of the cerebral cortex, largely made of neurons; trains the brain to discern information efficiently, helping it to focus only on the tasks at hand. For these reasons, bilingualism can protect the brain against dementia and Alzheimer s.