Dyslexia, which is also known as development reading disorder, happens when there is a problem in the area of the brain that helps guide and interpret the language. (PubMed Health). There are different types of dyslexia which have different causes. Trauma dyslexia is caused after there has been an injury to a person's head or certain part of the brain. (MedicineNet). Another type of dyslexia is called primary dyslexia, which is a dysfunction of the left side of the brain. (MedicineNet). Anyone with this type is barely able to read above a fourth grade level, and is received through their genes. Primary dyslexia is more commonly found in boys than girls. A third type of dyslexia is called developmental dyslexia, which is "caused by hormonal development during the early stages of fetal development." (MedicineNet). It starts to fade away as the child matures and is also mainly found in guys. So what really causes dyslexia? There isn't an exact answer yet, besides that it is hereditary and can be caused by early age hearing problems.