Type1 diabetes mellitus complications due to poor glycemic control affects brain functions negatively.In this work more than six powerful methods and tests were utilized : -hole board test. -pole test. -Nissl labelling and cell steriological quantification. -Haematoxylin and Eosin staining. -Immunohistochemical labeling. -Electron Microscopy. Behavioral tests were carried on long standing diabetic rats and control rats and the results were statistically compered,similarly the brains were studied and analyzed .There were significant difference between diabetic rats and control (non-diabetic). I am sure you will enjoy reading this book.