Effect of smell on the brain

Smell is nothing but a collection of molecules. When these molecules enter your nose, they bind with an olfactory receptor. This olfactory sense is located at the top of your nasal cavity. The moment an odour binds to this receptor, a signal is sent to the brain area for smell. This area is described as the bulbus olfactorius. Different collections of molecules control different parts of the bulbus olfactorius. This allows your brain to distinguish smells.

The bulbus olfactorius communicates with the rest of the brain, for example, the limbic system and the reptilian brain. These parts all have different functions.

The limbic system is the emotional side of the brain. Think emotion but also memory. Because the olfactory bulb is connected to the limbic system, some smells trigger memories. Think of the smell of grandma’s apple pie. Besides memory, the limbic system also controls emotion. As a result, smells can trigger certain emotions.

In addition, the bulbus olfactorius also controls the reptilian brain. The reptilian brain is the survival brain. Think about finding food or detecting danger. An example is smelling food and smelling fire or gas.

Because smell is closely linked to the brain, many smells have different effects on the brain.


The scent of ginger can help with nausea and has an activating effect on the brain.


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The scent of eucalyptus can improve respiratory function and reduce symptoms of infection or allergy. In addition, the scent has a relaxing and uplifting effect which helps with anxiety, fear and improving concentration. The scent of eucalyptus can also help fight insects.


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The scent of bergamot helps against stress, has an antidepressant effect, improves sleep quality and reduces anxiety.


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The scent of lemongrass can reduce anxiety and fear also it can be used as an eco-friendly insecticide and to clean the air.


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Jasmine has a relaxing effect on the body.


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The scent of rosemary protects the body from stress, improves short-term memory, reduces drowsiness and improves alertness.


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The scent of mint has a cooling effect on the body, can reduce nausea and improves memory and alertness.


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The scent of chamomile can help reduce stress, anxiety and depression. In addition, the scent of chamomile has a positive effect on the respiratory system, for example in cases of laryngitis.


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The scent of lavender has a calming effect on the body, can be stimulating, reduces anxiety, improves sleep quality, reduces depression and can reduce symptoms of menopause.


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The scent of orange blossom has a calming and soothing effect on the brain, improves sleep quality and reduces sleep disorders.


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The scent of vanilla has a relaxing effect on the brain. As a result, it reduces stress, anxiety, fear and depression, among others.


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The scent of basil has an antidepressant effect.


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