Imagine waking up one morning and discovering that your financial circumstances have taken an extraordinary turn: you just received a huge financial windfall. Maybe you won the lottery, or a stock market investment paid off, or you got a job offer that triples your current salary.

As a MIT neuroscientist, I've always been fascinated by the intricate dance that occurs within the brain during these life-altering moments. Can coming into a financial windfall really bring lasting happiness?

Here are three remarkable things that happen to your brain when you unexpectedly receive a large sum of money overnight:

1. Get ready for a dopamine deluge

The prospect of newfound riches triggers a surge in dopamine levels, generating excitement and pleasure. Unfortunately, humans tend to adjust to extreme lifestyle changes over time, so any rise in happiness is not always for the long-term. 

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This phenomenon is called the "Hedonic Treadmill," where we eventually get used to our new life and return to our baseline of happiness.  

A similar experience happens during shopping trips. When you leave the store with a new item, that can elicit an ecstatic feeling that is often more impactful than the item itself.

2. Up next: the five stages of grief

Experiencing the five stages of grief upon winning the lottery might seem counterintuitive, but this emotional journey can actually offer valuable insights into the complexity of such a life-altering event. 

1. Denial: Following shock and disbelieve, denial could follow, with the winner grappling to comprehend the sudden shift in fortune.
2. Bargaining. As reality sinks in, bargaining could emerge, as the individual negotiates with themselves about how to manage the newfound wealth. Feelings of guilt or remorse might surface, as the winner reflects on their own worthiness of such a windfall.
3. Anger. Eventually, anger might arise, directed towards societal expectations or personal doubts, leading to depression. 
4. Depression. The burden of responsibility of newfound wealth, and the decisions around it can lower mood and make it feel like life was easier without it. 
5. Acceptance. Ultimately, acceptance can settle in, as the individual works through their changed reality and forges a path forward with their newfound wealth.

3. Shifting perspectives and social dynamics

As your financial status shifts, your social dynamics can, too. Once word gets out about your new situation, you may be inundated with requests for money — and feel that your privacy is completely shattered.

The brain's assessment of how you are perceived by your social circle can activate its threat detection system, and potentially trigger feelings of isolation or distrust. 

But thanks to a process called "neuroplasticity," the brain also has an incredible capacity for change. So even though these interactions can feel unsettling, you also have all the tools you already need to create the boundaries to protect you in this new normal. 

Start by keeping a small circle of trusted people around you, meditating regularly and journaling about your decision making, whether this is what you spend or who you spend time with.

How to build happiness that lasts

My best advice is to take a personal inventory of all the material and emotional changes that have occurred. That means paying attention to both your bank account and how people are reacting differently around you. It never hurts to write it out, or enlist a good friend or therapist as a sounding board.

From there, make a deliberate plan about how to distribute your assets to create financial security and longevity rather than frivolous spending. I recommend seeking out a trusted financial advisor to hold you accountable if you know you can't do this on your own.

Even taking steps like doing regular exercise, implementing deep breathing techniques, eating nutritious diet and getting enough rest can create a scaffolding that makes it easier for us to train our brains to adapt in healthy ways.

Dr. Tara Swart Bieber is a neuroscientist, medical doctor and senior lecturer at MIT Sloan. She is the author of "The Source: The Secrets of the Universe, the Science of the Brain," and hosts the podcast Reinvent Yourself with Dr. Tara. Follow her on Twitter and Instagram.

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