“If you want to find the secrets of the universe, think in terms of energy, frequency and vibration.” – Nikola Tesla
Have you ever found yourself so moved by a melody, harmony or bass line that all exterior thoughts figuratively wash away with the currents? Whether it be techno, house, rock or hip hop, music is reliably accessible and an easy gateway to expressing emotions. An art form that speaks to such a vast range of emotions, the practice of music and therapy used simultaneously have had many successful rounds of response. Studying the effects of sound and music on our neurons and connecting those findings to a psychological vantage point for music therapy can be the answer to problems beyond our imagination.
The first step to understanding conscious listening is grasping how our billions of neurons receive signals. The brain is composed of neurons that all interact and communicate between themselves using neurotransmitters. There are two aspects in this communication: electric and chemical. In layman's terms, the neurotransmitters are electrical signals and hormonal signals at the same time. The levels of these electrical signals is measured by electroencephalography (EEG), which can then be graphed to generate brainwave patterns. The neurotransmitters are consisted of different hormones, such as endorphins, dopamine, serotonin and more. However, there are also different electrical signals. There are four different categories of brain wave patterns and each one is characteristic of a specific brain state; that is to say that each state is responsible of a body and mind state at the end. For example, when we observe gamma waves on the EEG, we observe muscular contractions and rapid eye movements, which matches with an active body state.
As there are four categories of brain wave patterns, we connect that the most ideal wave is alpha. In order to achieve this wave, electrical activity must be slightly decreased; this can lead to increases in endorphins, and dopamine. Focus practices such as chanting, allow the electrical patterns in our brains to slow down and relax, stabilizing it into the alpha wave range. However, there are other ways to control our EEG's. The human brain tends "to change its dominant EEG frequency towards the frequency of a dominant external stimulus (such as music, or sound)." 
Nowadays, music therapy can be easily understood as patients' usage of percussion instruments and voices to understand their responses to improvised music. Though simple sounding, music therapy sessions can range over a wide array of practices, as each therapist and patient relationship is different. Over time, patients are able to use instruments to reflect their emotional states, while building trust with the therapist. 
Different emotions invoke more or less creative activity. While some people create their best work whilst in a great mood, others draw from struggle and hardship in their creative process. The role of music plays an important part in helping us feel certain things; a slow, soft song may relax us, or make us feel sad, whilst a faster, upbeat song can help us get excited for something. Music tempo and tone are the two most important elements in touching on the human emotion.
Icelandic professors Saarikallio and Erkkila have conducted extensive studies on mood and music, and came to the conclusion that music helps us feel more empathetic, and more in touch with others’ emotions. It helps the listener understand feelings on a different level; whilst most feelings are the result of an experience, music allows us to gain the result of the experience without actually going through it.
A scientific experiment that was carried out on some patients with Alzheimers showed that musical therapy, when practiced at regular intervals, provokes an signification augmentation of the level of melatonin. If the melatonin is known to be "the hormone of sleep" (responsible for de-clenching the biologic rhythms), it equally plays an important role in the regulation in the blood pressure. In addition, it stimulates your immune system. 
There is no doubt that growth in technology has shifted the way music is shared. But how does this affect us in our every day lives? 200 years ago, if you wanted to hear music you would have to see a live band or orchestra perform. Today, with the flick of a finger we can listen to our favourite artists and tracks, and discover new music. We tend to create friendships based on musical preferences, resulting in inter-personal groups. Music preference can serve as an identification for many people, indicating that the ways in which we share music has affected the ways we meet people and organize our own social groups.
On the other hand, musical preference can be determined by your mood. It has been proven that during exercising, the listener may choose music that is loud with a fast tempo in order to keep their heart rate beating faster, inducing motivation to continue with the work out. After exercising, however, more soothing music is generally preferred, with softer tones and a slow tempo in order to help relax the body. People will prefer music which helps to balance their immediate environment. 
Through analysis of different scales of music therapy, from psychical to emotional usages, we can understand that our brains are predisposed to be affected by sounds and frequencies. To a lesser extent than trauma, music can be used whenever accessible in order to contain or express emotions. Understanding that we can control our EEG to focus on external stimulus, such as music, we can naturally create pleasure, concentration, and emotion. Working itself around expression, as well as comprehension, the ranges and styles of music are innumerable and will eternally touch every part of our lives.