This is a good descriptor of what bipolar mania can do to a person's perceptions and thinking.
False euphoria is the beginning stage of true bipolar disorder. Behavior is similar to that seen with drug use, a cocaine-like high. People with euphoric mania say they feel great/wonderful/beautiful/fantastic, but make many mistakes such as recklessly spending too much money, having sex with anyone who looks appealing, sleeping a lot less and not getting tired and ultimately making very poor life decisions.
It's common for people with full-blown euphoric mania to stay up for weeks, start very risky businesses or simply pick up and leave their current life. Euphoric mania can be very cruel and selfish as the emphasis is strictly on the person with bipolar. The person can be extremely reckless and unable to judge the safety or effect of their behaviors. There will be rapid and sometimes violent mood swings, rage alternating with maniacal laughter.
This type of mania can lead to a lot of drug and alcohol use as the person feels so good they lose perspective on the amount they consume. Euphoric mania always starts out feeling great, but ultimately the person comes down and often sees a path of destruction that is hard to clean up.
Bipolar patients have difficulty seeing that their behavior is out of line in an acute manic episode. The massive high, which seems abnormal to us, seems normal to them, and there is an unfortunate tendency to self medicate.
At more extreme levels, up to 70% of people in a manic state and 50% of all individuals with bipolar disorder experience psychosis, or a break with reality, along with loss of ability to reason. Of this 70%, over half are euphoric psychotic manias, which are particularly difficult to diagnose as they can be so appealing and fun to the people around the manic person. Manic behavior attracts people who want to join in on the ride.
Left unmedicated, people experiencing bipolar psychosis will resist treatment, as they are convinced nothing is wrong with them, they are sure of their reasoning and enjoy the high.
During a manic episode, the person's behavior feels "right," obvious and makes very clear sense, even if it makes no sense to those around the patient or is extremely risky. After the manic episode has run its course, it may be possible for the patient to see how unrealistic, unreal and out-of-touch with reality they were, but this isn't possible during a manic episode.