How deficient levels of neurotransmitters cause stress responses

Deficiencies in neurotransmitters can cause a significant reaction in a person’s ability to process and react to external stimuli appropriately. Everybody has to deal with daily stressors in life, but not everybody reacts to stress the same way. How a person responds to stressors has much to do with the levels and transmission of the neurotransmitters epinephrine, norepinephrine and dopamine. These neurotransmitters increase heart rate, metabolism, blood vessel constriction and bronchial dilation, all of which are characteristics of the fight or flight biological and psychological response.

How it works

When a person perceives a threat, whether the threat is real or not, the signal from an external source of harm causes the hypothalamus to send an emergency message to the autonomic nervous system, which sets the tone for how the person responds to the perceived threat. The sympathetic nervous system activates a part of the adrenal gland named the adrenal medulla, which releases hormones into the bloodstream. Large muscles and glands tense up and the heart rate speeds up.

The body has inhibitory and excitatory neurotransmitters, which are all derived from amino acids that are naturally produced by the human body. Inhibitory neurotransmitters slow things down and act as the body’s natural tranquilizing system; excitatory transmitters have the opposite effect, and the two types balance each other out. Inhibitory transmitters serve as an aide to induce sleep, promote calmness and decrease aggression. Excitatory neurotransmitters include dopamine, histamine, norepinephrine, epinephrine, glutamate and acetylcholine while inhibitory neurotransmitters include GABA, serotonin, taurine and more.

The different neurotransmitters

Serotonin helps control many functions such as appetite, compulsivity, libido, aggression, social anxiety, mood and sleep. Medications that are usually prescribed to treat depression act by blocking the reuptake of serotonin, causing more serotonin to stay in the synapse on which the receiving neuron could bind. Low levels of serotonin can cause depression, anxiety, panic attacks and low energy. High levels of serotonin can cause sedation and a sense of well-being. Too much serotonin can cause “serotonin syndrome” of which can be fatal. Symptoms of “serotonin syndrome” include violent trembling, profuse sweating, insomnia, nausea, teeth chattering, shivering, aggressiveness and agitation (NIMH 2013).

Dopamine is mainly involved in controlling movement, as well as aiding the flow of information to the front of the brain. In turn, this process is linked to thoughts, emotions and the reward systems in the brain. It has a large portion of control over the amount of pleasure that a person feels. Studies suggest that a deficiency in dopamine can cause problems with a person’s ability to move freely as well as creates problems in a person’s emotional and cognitive functions. On the other hand, when dopamine levels are too high, it can cause a person to have lapses in cognition, poor attention span, poor focus abilities, become aggressive, anxiousness and generally hyperactivity. An example of a disorder that can be attributed to high levels of dopamine are attention disorders such as attention deficit hyperactivity disorder (NIMH 2013).

Norepinephrine, otherwise known as noradrenaline, is a stress hormone and neurotransmitter that affects a person’s attention span and can trigger memories of traumatic events. It also plays a role in the fight or flight response (along with epinephrine), triggering the release of glucose and increasing blood flow to skeletal muscles. Norepinephrine is synthesized from dopamine, and is released from the adrenal medulla into the blood as a hormone. Low levels of norepinephrine are linked to lower arousal (sedation), lower alertness and depression. High levels of norepinephrine cause over-arousal, irritability and an overly productive sense of concentration almost to the point of obsessing, which can cause stress and anxiety (Carver 2014).

Glutamate is an excitatory transmitter and when released, it enhances the electrical flow among brain cells required for normal function. Glutamate is an important neurotransmitter required for the normal functioning of early brain development. Mental health disorders that are linked to a deficiency of glutamate are obsessive compulsive disorder (OCD), schizophrenia, depression and autism.

Getting help

The levels of neurotransmitters in the brain can cause various issues with a person’s mental well-being. People can get their hormone levels tested, but getting neurotransmitter levels tested is complicated. When someone is treated for disorders such as chronic anxiety, acute stress disorder, depression or post-traumatic stress disorder, his or her psychiatrist can prescribe different medications that can assist in the pharmacological treatment of any mood or anxiety disorders one might be experiencing.

Psychotherapy is also extremely effective in treating mood disorders, anxiety or depression. Very often, the stress that people experience has more to do with their daily activities, such as how much exercise they’re getting and how they process external stimuli.

Cognitive behavioral therapy (CBT) is extremely beneficial in helping patients understand whether the thoughts and feelings they’re experiencing are based on reality or if they’re in part being experienced as a result of a chemical imbalance caused by insufficient levels of hormones and neurotransmitters.

If you or a loved one would like more information on mental health treatment for any issues related to anxiety or stress, you can call the Mental Health Helpline at 855-653-8178.