By the end of this section, you will be able to:
Mental health includes our emotional, psychological, and social well-being. It affects how we think, feel, and act. It also helps determine how we handle stress, relate to others, and make healthy choices.1 Mental health is important at every stage of life, from childhood and adolescence through adulthood.
Mental and physical health are equally important components of overall health. For example, depression increases the risk for many types of physical health problems, particularly long-lasting conditions like diabetes, heart disease, and stroke. Similarly, the presence of chronic conditions can increase the risk for mental illness.2
Yes, it’s important to remember that a person’s mental health can change over time, depending on many factors. When the demands placed on a person exceed their resources and coping abilities, their mental health could be impacted. For example, if someone is working long hours, caring for a relative, or experiencing economic hardship, they may experience poor mental health.
Mental illnesses are among the most common health conditions in the United States.
There is no single cause for mental illness. A number of factors can contribute to risk for mental illness, such as
https://youtu.be/IaSpas9hWNQ?si=w6vpzfCFttuRehPa
By the end of this section, you will be able to:
Substance abuse is a pattern of compulsive substance use marked by recurrent significant social, occupational, legal, or interpersonal adverse consequences, such as repeated absences from work or school, arrests, and marital difficulties.
Addiction is a state of psychological or physical dependence (or both) on the use of alcohol or other drugs. The term is often used as an equivalent term for substance dependence and sometimes applied to behavioral disorders, such as sexual, internet, and gambling addictions.
Substance use disorder is the medical term used to describe a pattern of using a substance (drug) that causes significant problems or distress. This may be missing work or school, using the substance in dangerous situations, such as driving a car. It may lead to substance-related legal problems, or continued substance use that interferes with friendships, family relationships, or both. Substance use disorder, as a recognized medical brain disorder, refers to the use of illegal substances, such as marijuana, heroin, cocaine, or methamphetamine. Or the misuse of legal substances, such as alcohol, nicotine, or prescription medicines. Alcohol is the most common legal drug associated with substance use disorder.
Substance dependence is the medical term used to describe use of drugs or alcohol that continues even when significant problems related to their use have developed. Signs of dependence include:
Cultural and societal factors determine what are acceptable or allowable forms of drug or alcohol use. Public laws determine what kind of drug use is legal or illegal. The question of what type of substance use can be considered normal or acceptable remains controversial. Substance use disorder is caused by multiple factors, including genetic vulnerability, environmental stressors, social pressures, individual personality characteristics, and psychiatric problems. But which of these factors has the biggest influence in any one person cannot be determined in all cases.
The following are the most common behaviors that mean a person is using or misusing drugs or alcohol. But each person may have slightly different symptoms. Symptoms may include:
The symptoms of substance use disorder may resemble other medical problems or psychiatric conditions. Always consult your doctor for a diagnosis.
A family doctor, psychiatrist, or qualified mental health professional usually diagnoses substance use disorder. Clinical findings often depend on the substance, the frequency of use, and the length of time since last used, and may include:
Specific treatment for substance use disorder will be determined by your doctor based on:
A variety of treatment (or recovery) programs for substance use disorder are available on an inpatient or outpatient basis. Programs considered are usually based on the type of substance. Detoxification (if needed, based on the substance) and long-term follow-up management or recovery-oriented systems of care are important features of successful treatment. Long-term follow-up management usually includes formalized group meetings and psychosocial support systems, as well as continued medical supervision. Individual and family psychotherapy are often recommended to address the issues that may have contributed to and resulted from the development of a substance use disorder.
Neurons: In the simplest sense, the neuron consists of a cell body, axons, and dendrites.
Cell Body: The cell body contains the nucleus and is the site of metabolic activity. Most of the neurotransmitters that will eventually be released at the synapse are synthesized here.
Dendrites: These are small projections from the cell body that serves a receptive role in the physiology of the neuron. They receive incoming signals from other neurons and relay them to the cell body, where the signals are integrated, and a response will be initiated.
Axons: Generally, the outflow tract of the neuron. It is a cylindrical tube that is covered by the axolemma and is supported by neurofilaments and microtubules. The microtubules will help to transport the neurotransmitters from the cell body down to the pre-synaptic terminal, where they will be released.
Synapses: The synapse itself is the site of transmission from the pre-synaptic neuron to the post-synaptic neuron. The structures found on either side of the synapse vary depending on the type of synapse:
Anatomy & Physiology by Lindsay M. Biga et al. book's Figure 12.2.2 – Parts of a Multipolar Neuron: The major parts of the neuron are labeled on a multipolar neuron from the CNS.
The human brain is made up of approximately 86 billion neurons that “talk” to each other using a combination of electrical and chemical (electrochemical) signals.
The places where neurons connect and communicate with each other are called synapses. Each neuron has anywhere between a few to hundreds of thousands of synaptic connections, and these connections can be with itself, neighboring neurons, or neurons in other regions of the brain. A synapse is made up of a presynaptic and postsynaptic terminal.
The presynaptic terminal is at the end of an axon and is the place where the electrical signal (the action potential) is converted into a chemical signal (neurotransmitter release). The postsynaptic terminal membrane is less than 50 nanometers away and contains specialized receptors. The neurotransmitter rapidly (in microseconds) diffuses across the synaptic cleft and binds to specific receptors.
The type of neurotransmitter released from the presynaptic terminal and the specific receptors present on the corresponding postsynaptic terminal is critical in determining the quality and intensity of information transmitted by neurons. The postsynaptic neuron integrates all the signals it receives to determine what it does next, for example, to fire an action potential of its own or not.
Anatomy & Physiology by OpenStax College book's Figure 3. The Synapse. The synapse is a connection between a neuron and its target cell (which is not necessarily a neuron). The presynaptic element is the synaptic end bulb of the axon where Ca2+ enters the bulb to cause vesicle fusion and neurotransmitter release. The neurotransmitter diffuses across the synaptic cleft to bind to its receptor. The neurotransmitter is cleared from the synapse either by enzymatic degradation, neuronal reuptake, or glial reuptake.
https://youtu.be/NxHNxmJv2bQ?si=Nb-Dw5Te9O1KaTYH
Many people don't understand why or how other people become addicted to drugs. They may mistakenly think that those who use drugs lack moral principles or willpower and that they could stop their drug use simply by choosing to. In reality, drug addiction is a complex disease, and quitting usually takes more than good intentions or a strong will. Drugs change the brain in ways that make quitting hard, even for those who want to. Fortunately, researchers know more than ever about how drugs affect the brain and have found treatments that can help people recover from drug addiction and lead productive lives.
https://youtu.be/YefKGTu_Xf8?si=egX5-oTzdh57ZPzX
Most drugs affect the brain's "reward circuit," causing euphoria as well as flooding it with the chemical messenger dopamine. A properly functioning reward system motivates a person to repeat behaviors needed to thrive, such as eating and spending time with loved ones. Surges of dopamine in the reward circuit cause the reinforcement of pleasurable but unhealthy behaviors like taking drugs, leading people to repeat the behavior again and again.
As a person continues to use drugs, the brain adapts by reducing the ability of cells in the reward circuit to respond to it. This reduces the high that the person feels compared to the high they felt when first taking the drug—an effect known as tolerance. They might take more of the drug to try and achieve the same high. These brain adaptations often lead to the person becoming less and less able to derive pleasure from other things they once enjoyed, like food, sex, or social activities.
Long-term use also causes changes in other brain chemical systems and circuits as well, affecting functions that include:
Despite being aware of these harmful outcomes, many people who use drugs continue to take them, which is the nature of addiction.
No one factor can predict if a person will become addicted to drugs. A combination of factors influences risk for addiction. The more risk factors a person has, the greater the chance that taking drugs can lead to addiction. For example:
As with most other chronic diseases, such as diabetes, asthma, or heart disease, treatment for drug addiction generally isn’t a cure. However, addiction is treatable and can be successfully managed. People who are recovering from an addiction will be at risk for relapse for years and possibly for their whole lives. Research shows that combining addiction treatment medicines with behavioral therapy ensures the best chance of success for most patients. Treatment approaches tailored to each patient’s drug use patterns and any co-occurring medical, mental, and social problems can lead to continued recovery.
More good news is that drug use and addiction are preventable. Results from NIDA-funded research have shown that prevention programs involving families, schools, communities, and the media are effective for preventing or reducing drug use and addiction. Although personal events and cultural factors affect drug use trends, when young people view drug use as harmful, they tend to decrease their drug taking. Therefore, education and outreach are key in helping people understand the possible risks of drug use. Teachers, parents, and health care providers have crucial roles in educating young people and preventing drug use and addiction.
http://cnx.org/contents/14fb4ad7-39a1-4eee-ab6e-3ef2482e3e22@9.1
https://open.oregonstate.education/aandp/chapter/12-2-nervous-tissue/#fig-ch12_02_01
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