Anatomy & Physiology: Current Research
Open Access

The Complex Connection between Neurotransmitters and Mental Health

Eugene F Adiutori^{* *}Correspondence: Eugene F Adiutori, Department of Anatomy, University of Texas, Texas, USA, Email:

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Description

Neurotransmitters, the brain's chemical messengers, play a important role in regulating a wide array of functions, including mood, cognition, and behaviour. Serotonin is perhaps the most well-known neurotransmitter in the context of mental health. Often referred to as the "feel-good" chemical, serotonin is critical for mood regulation, anxiety, and happiness [1]. It is synthesized in the brain and intestines and affects virtually every part of the body, from emotions to motor skills. Anxiety and depression are correlated with low serotonin levels. Selective Serotonin Reuptake Inhibitors (SSRIs), a common class of antidepressants, work by increasing the availability of serotonin in the brain, thereby improving mood and anxiety symptoms. By preventing the reabsorption of serotonin into neurons, SSRIs enhance its positive effects on mood regulation [2].

Dopamine is another vital neurotransmitter that influences several functions, including motivation, pleasure, and motor control. It plays a central role in the brain's reward system, reinforcing behaviours that are essential for survival and providing the feeling of pleasure [3]. Dopamine imbalances have been connected to a number of mental health issues. For instance, excessive dopamine activity is associated with schizophrenia, characterized by hallucinations and delusions. Conversely, insufficient dopamine activity is linked to Parkinson's disease and depression, where symptoms include apathy and a lack of motivation [4]. Treatments for these conditions often aim to balance dopamine levels to alleviate symptoms.

The neurotransmitter norepinephrine, commonly referred to as noradrenaline, is essential for the body's "fight or flight" reaction in response to stress. It helps to increase alertness, arousal, and readiness to respond to potential threats [5]. In mental health, norepinephrine is closely linked to conditions such as depression and anxiety. Low levels of norepinephrine can lead to symptoms of depression, including lethargy and lack of interest in activities. Medications such as Serotonin-Norepinephrine Reuptake Inhibitors (SNRIs) work by increasing the levels of both serotonin and norepinephrine, thereby improving mood and energy levels [6].

The brain's main inhibitory neurotransmitter is Gamma-Amino Butyric Acid (GABA). It helps to reduce neuronal excitability throughout the nervous system, promoting relaxation and reducing stress. Low levels of GABA are associated with anxiety disorders, as they result in increased neuronal activity that can lead to heightened anxiety and panic attacks. Benzodiazepines, a class of anti-anxiety medications, enhance the effect of GABA, providing a calming effect that helps to alleviate anxiety symptoms [7]. The brain's most prevalent excitatory neurotransmitter, glutamate, is essential for mental processes including memory and learning. It facilitates the transmission of signals between neurons and is essential for brain development and plasticity. However, excessive glutamate activity can lead to excitotoxicity, which can cause neuronal damage and is implicated in conditions such as Alzheimer's disease and schizophrenia. Treatments targeting glutamate pathways are being explored to mitigate these effects and improve cognitive function in affected individuals [8].

Acetylcholine is involved in many functions, including muscle activation, memory, and learning. It plays a significant role in the autonomic nervous system and in the brain's ability to process and recall information. Deficiencies in acetylcholine are linked to cognitive decline and memory loss, as seen in Alzheimer's disease. Cholinesterase inhibitors, which prevent the breakdown of acetylcholine, are used to treat Alzheimer's disease, thereby improving cognition and memory [9].

The complex balance of neurotransmitters is essential for maintaining mental health. Imbalances in these chemicals can lead to a variety of mental health conditions, each with its unique set of symptoms and challenges. Understanding the role of neurotransmitters in mental health not only sheds light on the complex nature of these conditions but also guides the development of effective treatments. By targeting specific neurotransmitter systems, medications can restore balance and alleviate symptoms, improving the quality of life for those affected by mental health disorders [10].

References

1. Opladen T, Bertoldi M. Neurotransmitters … it is all about communication!. J Inherit Metab Dis. 2024;47(3):409-410.

   [Cross Ref] [Google Scholar] [PubMed]

2. Jahanabadi S, Amiri S, Karkeh Abadi M, Razmi A. Natural psychedelics in the treatment of depression; a review focusing on neurotransmitters. Fitoterapia.2023;169:105620.

   [Cross Ref] [Google Scholar] [PubMed]

3. Lawn T, Howard MA, Turkheimer F, Misic B, Deco G, Martins D, et al. From neurotransmitters to networks: Transcending organisational hierarchies with molecular-informed functional imaging. Neurosci Biobehav Rev. 2023;150:105193.

   [Cross Ref] [Google Scholar] [PubMed]

4. Colombel N, Ferreira G, Sullivan RM, Coureaud G. Dynamic developmental changes in neurotransmitters supporting infant attachment learning. Neurosci Biobehav Rev. 2023;151:105249.

   [Cross Ref] [Google Scholar] [PubMed]

5. Madsen TE, Liu S. Amino acid neurotransmitters and prognosis after stroke: nutrition as a modifiable factor to improve stroke outcomes. Am J Clin Nutr. 2023;118(4):737-738.

   [Cross Ref] [Google Scholar] [PubMed]

6. Nimgampalle M, Chakravarthy H, Sharma S, Shree S, Bhat AR, Pradeepkiran JA, et al.  Neurotransmitter systems in the etiology of major neurological disorders: Emerging insights and therapeutic implications. Ageing Res Rev. 2023;89:101994.

   [Cross Ref] [Google Scholar] [PubMed]

7. Gupta S, Dinesh S, Sharma S. Bridging the mind and gut: Uncovering the intricacies of neurotransmitters, neuropeptides, and their influence on neuropsychiatric disorders. Cent Nerv Syst Agents Med Chem. 2024;24(1):2-21.

   [Cross Ref] [Google Scholar] [PubMed]

8. Pidathala S, Liao S, Dai Y, Li X , Long C , Chang CL, et al. Mechanisms of neurotransmitter transport and drug inhibition in human VMAT2. Nature. 2023;623(7989):1086-1092.

   [Cross Ref] [Google Scholar] [PubMed]

9.  Soden ME, Yee JX, Zweifel LS. Circuit coordination of opposing neuropeptide and neurotransmitter signals. Nature. 2023;619(7969):332-337.

   [Cross Ref] [Google Scholar] [PubMed]

10. Wilson SK, Thomas J. BH4 as a therapeutic target for ADHD: Relevance to neurotransmitters and stress-driven symptoms. J Atten Disord. 2024 Jan;28(2):161-167.

    [Cross Ref] [Google Scholar] [PubMed]