From New York - A new report published in Neurology links viruses that cause cold sores to cognitive problems. Researchers studied over 1,600 individuals with an average age of 69. Participants had their thinking and memory skills tested once a year for 8 years. Participants also had their blood tested for 5 common viruses: three types of herpes viruses, chlamydia pneumoniae, and Helicobacter pylori. Results showed that individuals with higher levels of infection had a 25% raised risk of low test scores measuring cognitive performance. Infection was not, however, associated with declining abilities over time