Serial 7 is a game that tests how quickly you can subtract 7 in a row from a given number.

It is a slight variation of the serial 7 subtraction test, which is one of the items on the MMSE(Mini-Mental State Examination).
A starting number between 94 and 100 is randomly selected, and you measure the time it takes until you can't subtract any more 7.

The subtraction of consecutive sevens task is used to test attention and memory, and consistent testing can help improve brain skills such as attention and memory.
It can also help prevent cognitive decline that occurs with everyday activities and reduce the likelihood of developing dementia.
They can also be used to see how an individual's cognition changes over time.

Recommended for users interested in brain health and training, and dementia prevention.