Your question begins with a false assumption. No organisms -- including human beings -- have a spirit. The spirit is a religious fabrication.

1. First give me a definition of spirit.
2. Show me evidence that the entity represented by this definition is real.
   Now we can start discussing how this entity is connected with our biological lifespan and if it continues after.
   BUT
   There is no evidence for anything, and as no one can remember any past life, nor we have any evidence that the conscience can exist outside the neuron circuits of the brain.
   So the best answer is:
   There is no definition that is not self contradictory about what is the spirit.
   If you are talking about continence, it fades away as the synapses stop working,

I'm an agnostic because I don't know for certain where our spirit goes when we die. OTOH, I'm an atheist because i'm pretty certain we go to the same place that our dogs, cats & the elephants & bears go to. The oblivian we came from, we return to. The end of us.

I don’t know. Reincarnation would be interesting but all of the options are speculative. I would assume you just stop existing.

Reincarnation rocks...I mean, the idea of it.

Pffffft! That's all, folks.

Physics mandates that energy can not be destroyed. Energy can only transform into a different energy. The body is in the tree thru the water or carbon dioxide it absorbs. At the cosmic or quantum level physics breaks down. So I like to think that my Diva who just passed into the cosmos yesterday is still with me tho she is in the freezer until I can dig her grave. I hope there is room here on these 4 acres.

Doesn’t matter. You’ll find out soon enough

The sense of being an individual self is just an illusion. Time is an illusion. Our entire perspective of the physical world is nothing but a dream.

We are collectively a single entity, immortal by default because time doesn’t exist.

That’s my opinion anyway.

no one knows we can guess make up personal beliefs, mash science and hope together and come up with a plausible sounding yet ultimately unproven hypothesis anyone that says they know is a liar

Whatever it is, it's the same thing for everybody. Doesn't matter about your behavior.

There is some evidence for reincarnation if the stories can be believed. The little boy who's supposed to be the reincarnation of Lou Gehrig. The boy who has described his life as a WW2 pilot who was shot down and perished. The child in India who named names and met her "family", from a previous life, in a town near where she was "reborn".

Generally I define the mind as thoughts and memories. through surgery and probes we know thoughts and memories are chemical reactions in brain cells, when the brain is damaged the mind is impaired, when the brain is dead the mind doesn't suddenly become independent of those chemical reactions and just float off. Chemical reactions cause our muscles to contract, when we damage a muscle the contraction is impaired, when the muscle dies there is no more contractions. Why would we think the contractions would continue without the muscle? So when then brain dies the 'mind' is no longer generated by the brain. As to the psychological aspect dealing with thoughts about death I like this quote by Mark Twain, "I had been dead for billions and billions of years before I was born, and had not suffered the slightest inconvenience from it." If I had to cope with the knowledge I would die soon I hope I would take to heart my mantra, thankfulness enriches us, forgiveness frees us, and kindness betters us all.

Have any of you heard of DMT, and how it may be involved in our conscious experience? I learned a bit about it and it seems to dilate time for people. If it is released in large quantities when we die, maybe we would have transcendent experiences like subjects do in tests, but they would last for subjective eternities, and this phenomenon would amount to an afterlife.

There is no such thing. In this case a little more than usual due to the typo.

No where. There is nothing after death.

I keep wondering what happened to my dog or cat's mind and spirit after they died. Every now and then I hear a "meow" and I wonder if that is from my cat. Is he trying to communicate with me?
Of course we will get reincarnated. The universe re-uses star dust and another dimension is where the believers have now put their god so they can protect him.