Cognitive impairment is a very broad term defining anything that blocks someones cognitive processes. As Alzheimer's is a mental illness that affects cognitive processes it is fair to say that this is the chief symptom.
These symptoms can be early indicators of Alzheimer's:
- Forgetting recent conversations or events
- Forgetting names of places or objects
- Regularly repeating themselves
- Taking longer to make decisions and being unwilling to try new things
These are a few indicators but are not exclusive to Alzheimer's, it may be that someone is simply having a bad day, it is good to keep a record of any symptoms and if they are developing to see your local doctor.