Cognitive reserve (CR) is the brain's ability to maintain cognitive function despite age-related brain changes, damage or disease. It reflects an individual's capacity to cope with these changes by utilizing pre-existing cognitive strategies or developing compensatory mechanisms. The CR hypothesis presumes higher tolerance of Alzheimer’s disease (AD)-related pathology without functional decline for those with high education yet more rapid decline after AD onset. However, evidence supporting the second part of the hypothesis has been largely confined to U.S.-based studies.

A new study by researchers from Boston University Chobanian & Avedisian School of Medicine

has found that people with more years of education lost their memory and thinking abilities faster after being diagnosed with AD, compared to those with less education. These findings now provide evidence for the CR theory using real-life data from older adults from England, Germany and France.

- For middle-aged people, reducing TV time by 60 minutes a day decreases likelihood of depression by 11 percent, and reducing TV time by 90 or 120 minutes decreases likelihood of depression by over 25 percent.  

- These benefits apply to middle-aged people not the young or the elderly. 

- The benefits do not apply to switching TV time for household chores.

Researchers find that zeaxanthin, best known for protecting vision, can also strengthen the cancer-fighting activity of immune cells.

Researchers observed positive interactions, in which one disease favours the onset of another, such as between asthma and Parkinson's disease; and negative interactions, in which some groups of patients with one disease may be protected from developing others, such as between cancer and Huntington's disease.