Toxic Tau (IMAGE) UT Southwestern Medical Center Caption Abnormal accumulations of a protein called tau can collect inside neurons, forming tangled threads and eventually harming the synaptic connection between neurons. Credit: National Institute on Aging. Credit UT Southwestern Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.