Since ancient times, the fact of speaking only with traits of madness or suffering from some mental illness has been associated. Get that idea out of your head, because more than disadvantages it can have many benefits for your health and for your brain. As adults we try to avoid talking to ourselves so that no one gets a bad image of us, but it is a practice that children do a lot, being a very important part of their good emotional and mental development. 
What’s good about talking alone
Help organize your thoughts
How many times are those conversations you have with yourself to tell you the things you should do throughout the day? Hence, many studies point out that one of the main benefits of talking to yourself is that it helps you organize your thoughts and reduce stress in your day to day. Your mind will prioritize and you will be able to reach everything without problem.
You gain self-esteem
“I can”, “You can”, “Let’s go for it”, “Nothing is going to stop me”. Surely you have repeated these phrases to yourself, but also out loud on countless occasions when you have had the need to feel stronger in the face of tough challenges that life presented to you. You speak to yourself and you do it to gain confidence in yourself, to improve your self-esteem and to overcome any type of adversity that may arise before your next goal. “There are no limits”, “I’m the best”, “I’m going to get it”. Only if you believe in yourself can you achieve anything you want.
Increases concentration
Talking alone is an excellent resource to escape the world and achieve greater concentration on daily tasks. Remember when you were a student, how did you prepare for an exam? what was the best way to concentrate? You would probably lock yourself in your room, underline the basic concepts with a fluorescent pen and, after a leisurely reading, repeat them out loud. And it is that this way you concentrated better, in addition to memorizing the main points faster.
Makes you feel better
Human beings are sociable by nature and need others to grow as a person and to learn, but also to complement each other and realize their strengths and weaknesses. We need to relate to others because our body asks us to communicate and tell what happens to us. And what happens when that is not possible? When after a difficult working day in which nothing has been done on your part (you have arrived late, you have lost all the documentation on the computer, they have sent you a report at the last minute and, to top it all off, you have been angered by your boss for delivering the said study wrong) you have to tell someone the “chronicle of the worst day of your life”, but you don’t have any friends around. The most immediate consequence is to tell yourself and establish a conversation with you to vent. You will release all the tension and you will feel much better!
Improve your memory
Imagine the situation: you are in your living room watching television and your favorite channel broadcasts that question and answer contest that you like so much because, as you say, you always learn something new. At one point in the program, the presenter launches a question that leaves the participant speechless that day, while you at home shout out loud the solution to the enigma. This impulsive act helps your brain activate additional information about that concept, refreshing and updating itself.
Allows better control and management of emotions
Surely it has happened to you that when you speak you only do it in the third or second person, as if you were establishing a dialogue with someone. It is another way of talking to yourself that will bring you great benefits, such as maintaining a calmer and more relaxed attitude, having more confidence in yourself, making decisions in an intelligent way and performing better at work.
When expressing thoughts out loud becomes a problem
Talking alone will bring you all these benefits that we have told you about above as long as you do it with respect and not attacking yourself. Do not do it to punish yourself, to reproach you for things you have done wrong or to punish yourself because only then will those thoughts that you are saying out loud turn against you. Goodbye to feeling better, out of control of emotions, goodbye to mental organization… Speaking in this tone and with those negative connotations can be almost worse than silence. Give up that attitude, stand in front of a mirror and start talking to yourself as a sweetheart, just as if you were talking to a loved one: your partner, your best friend, your mother, your child…
Another circumstance in which speaking alone can become a big problem is when there are hallucinations in those conversations or when the person hears other voices that are not their own. It would be, then, mental illnesses such as schizophrenia.