What are Neurotransmitters?
What are Neurotransmitters and How Do They Function?
Neurotransmitters are chemical messengers in the brain that play a crucial role in transmitting signals across a synapse to other cells, which can be another neuron, a gland, or a muscle cell. They influence mood, cognition, and behavior. Neurotransmitters can either excite or inhibit the neuron, causing it to fire off the message or suppress it, respectively.
- Epinephrine: Also known as adrenaline, this neurotransmitter is involved in the body's "fight-or-flight" response.
- Histamine: This excitatory neurotransmitter is reflective of allergy or inflammation in the system.
- Endorphins: Released by the pituitary gland and hypothalamus, these neurotransmitters can alleviate pain, lower stress, and enhance mood.
- Glycine: This inhibitory neurotransmitter is released by nerve endings in the spinal cord.
How are Neurotransmitters Linked to Autism?
Research has found strong links between certain neurotransmitters and autism. For instance, people with autism tend to have higher levels of serotonin in their blood and lower levels in their brains. There is also evidence of low levels of GABA in the left frontal lobe of people with autism. Anomalies on chromosome 15 have been linked to the development of ASD and deficiencies in GABAA receptors.
- Serotonin: Dysfunction in the gut is linked to the severity of the disorder in people with autism.
- GABA: A study found low levels of GABA in the left frontal lobe of people with autism. Deficiencies in GABAA receptors have been linked to the development of ASD.
What is the Role of Neurotransmitters in Child Disability?
Inherited disorders of neurotransmitters are a group of syndromes caused by disturbances in neurotransmitter metabolism or transport. These disorders require specialized diagnostic procedures to detect. In infants and children, spontaneous release of neurotransmitters in the brain can present with recurrent seizures, intellectual disability, and autistic features.
- Dopamine: This neurotransmitter plays a key role in the behaviors altered by both ADHD and ASD, supporting motor initiation and coordination, motivation, reward and social behavior, as well as attention and higher cognitive function.
- Glutamate, GABA, and Dopamine: A study indicates a reciprocal relationship of higher serum level of glutamate and lower levels of GABA and dopamine across the severity groups in intellectual disability.
How do Neurotransmitters Influence Mood?
Depression, anxiety, and other mood disorders are thought to be directly related to imbalances with neurotransmitters. Neurotransmitters such as serotonin, dopamine, and norepinephrine are some of the more common neurotransmitters that regulate mood.
- Serotonin: This neurotransmitter is known to regulate mood, social behavior, appetite, digestion, sleep, memory, and sexual desire and function.
- Dopamine: It is associated with pleasure and reward, and its imbalance can lead to mood disorders.
- Norepinephrine: It is involved in the body's stress response and is linked to mood disorders when out of balance.
What is the Relationship Between Neurotransmitters and Neuroplasticity?
Neurotransmitters, such as dopamine and serotonin, affect neuroplasticity, which is the brain's ability to adapt and change to current circumstances. Dopamine improves learning and memory formation, while serotonin modulates neuroplasticity, especially during early life. Research also suggests that serotonin reuptake inhibitors trigger reactivation of juvenile-like neuroplasticity.
- Dopamine: It improves learning and memory formation.
- Serotonin: It modulates neuroplasticity, especially during early life.
What Role do Neurotransmitters Play in Child Development?
Neurotransmitters and modulators are important for the development of neuronal circuits and neural trafficking in embryos. They also affect gene expression in nerve cells, which can have long-term effects on how nerves respond to stimulation, function, and grow. Some neurotransmitters that play a role in child development include GABA, monoamines, dopamine, ACh, and acetylcholine.
- GABA: This neurotransmitter is important for embryonic development before synapse formation.
- Monoamines: These include dopamine, serotonin, and norepinephrine, and are important for fetal development and placenta function. They are also involved in neuronal migration, differentiation, and cell proliferation.
- Dopamine and ACh: These neurotransmitters are associated with motivation and attention. They can also positively impact learning and synaptic plasticity.
- Acetylcholine (ACh): This neurotransmitter is important for memory development and learning.