What is happiness from a neurophysiological point of view

From the point of view of cognitive sciences, it is impossible to develop a reliable methodology that would allow us to study what happiness is, because for each person it depends on different factors. Measurable only certain aspects of our behavior and emotional state, but perhaps they can provide a clue to what processes occur in the brain of a happy person.

Our good mood is governed by individual stimuli that can cause different intensities of positive emotions in different people (from mild joy to euphoria). Therefore, it is almost impossible to systematically study the brain of a happy person in order to answer the question what happiness is.

For someone, happiness is wealth, for someone - love, and someone will say that happiness lies in having a purpose in life.

The subjective experience of happiness, however, can be divided into two relatively objective components: emotional (the intensity of good and bad emotions) and cognitive (the integrity of our consciousness). Thus, the “recipe” for a happy life includes two components: positive emotions (and, in particular, the absence of negative emotions) and a sense of meaningfulness of what is happening in the world around us and with ourselves. Below we will focus mainly on the first of them.

Pleasure Lever

Emotion is a mental state (positive or negative) that is largely responsible for a complex set of brain structures - the limbic system (it is also responsible for regulating more basic human functions, such as smell and circadian rhythms). In simple terms, emotion is a person's reaction to a certain external (from the outside world) or internal (for example, mental) stimulus and what this stimulus may follow.

Negative emotions, such as fear or disgust, can be easily traced in the human brain: the amygdala, or amygdala, is responsible for them. And if fear and disgust are basic emotions developed in the process of evolution, then with positive emotions everything is much more complicated.

Psychologists have long believed Towards to be a functional neuroanatomy of pleasure and happiness. that positive emotions are largely associated with having fun.

To trace the processes occurring in the brain of a happy or happy person, scientists study the emotional response of a happy person.

Research on pleasure and the neural correlates associated with pleasure has its origins in behavioral experiments in the early 20th century. The object of studying behaviorism as a direction of psychology is behavior, in particular - the behavior of an individual as a reaction to a certain stimulus (external or internal). A famous experiment conducted by American behavioral psychologists James Olds and Peter Milner in 1954 led to the discovery of an important part of the brain, which they called the "pleasure center."

The experiment involved rats that were sitting in a special box, Skinner's Box. with electrodes implanted in the limbic system. Scientists wanted to find out what reaction of an individual would lead to stimulation of different parts of this area. Low current shocks were launched across the electrodes each time the rat entered a certain corner of the cage.

Scientists found that when stimulated, the rat returned to the corner over and over again. Later, scientists tested whether the effect would persist if the animal was responsible for receiving the reward itself, and gave him the opportunity to receive stimulation by pressing a lever. The rat, ignoring the actions necessary for survival, pressed the lever until it died of exhaustion.

Based on this, Olds and Milner concluded that brain stimulation caused pleasure in mice, and that the electrical stimulus itself was a good positive reinforcement. Two areas of the brain that are subject to stimulation have been called by scientists as part of a large collection of brain structures called "pleasure centers": the septal region adjacent to the corpus callosum, and a small part of the striatum - the nucleus accumbens.

Subsequently, experiments with implanting electrodes into the brain in the area of the "pleasure center" were tried to be carried out in humans (the psychology of the 60s was not very ethical by today's standards), but this practice was soon abandoned. Later, the study of "pleasure centers" led to the discovery of a substance released in the brain in the process of obtaining pleasure - dopamine.

There are several “pleasure centers” in the brain: in addition to the above-mentioned parts of the limbic system, scientists also distinguish some parts of the cerebral cortex (for example, the orbitofrontal cortex and insular lobe). The exact functions of each of them have not yet been established. In addition, "pleasure centers" are most often viewed as parts of a more complex system - a collection of brain structures called the reward system. Such a system is responsible for several aspects related to receiving a reward: the desire for a pleasant stimulus, positive emotions (pleasure) in response to a pleasant stimulus, and the reinforcement of the behavior that led to the receipt of this stimulus.

Molecules of happiness

Several neurotransmitters are responsible for receiving pleasure in the brain - chemicals that transmit a signal between two neurons through a synapse, the point of contact between two neurons. We will look at the properties and functions of the most basic ones.

Dopamine is a neurotransmitter from the monoamine group, a biochemical precursor of norepinephrine. Dopamine has several very different functions, including controlling motor and executive (cognitive) activity. Dopamine is also a neurotransmitter involved in activating the reward system.

The neurons of the "pleasure centers" release dopamine in the process of reaction to a certain stimulus pleasant for a person, as well as to the anticipation of receiving it.

The stimulus can be anything: sexual, sensory, external, internal. It may be food, or it may be the face of a loved one. Everything that pleases us gives us pleasure; pleasure, in turn, evokes joy.

Another important neurotransmitter involved in the formation of positive emotions is serotonin … Like dopamine, serotonin comes from the monoamine group. Among the functions for which the production of serotonin is responsible, in addition to regulating mood, are memory and sleep.

Dysfunction of serotonergic pathways is one of the causes of clinical depression and anxiety - a kind of "antonym" of happiness. That is why many antidepressants work on the principle of inhibiting the reuptake of serotonin: in a mentally unhealthy brain, the production of serotonin as a neurotransmitter slows down, and such drugs are able to restore this process.

Another group of neurotransmitters, endorphins, refers to neuropeptides that act on opioid receptors. Neuropeptides are produced in response to stress as a defense mechanism and to reduce pain. Some opioids (such as morphine and its analogs) also act on opioid receptors and produce the same response, from pain relief to euphoria. That is why, in the pursuit of easy happiness, people begin to use opioid drugs.

The feeling of euphoria from drugs is available only for the first time, then their use is necessary to relieve withdrawal symptoms, or simply "withdrawal".

Also worth noting endocannabinoid neurotransmittersfor example anandamide and 2-arachidonoylglycerol. They are involved in controlling stress responses and regulating the level of arousal. Cannabinoids, the active ingredients in the cannabis plant from which marijuana is derived, also act on cannabinoid receptors.

Neuropeptide oxytocin, produced in the hypothalamus, is responsible for the establishment of social bonds and the development of warm, positive emotions in relation to someone. Thus, oxytocin is released in large quantities during childbirth, which contributes to the establishment of a strong bond between the mother and the baby, and also helps the mother during the feeding process. Small amounts of oxytocin are also released during orgasm, so it is believed to play an important role in sexual pleasure.

Finally, the last neurotransmitter we'll look at is norepinephrine(also known as norepinephrine) is a monoamine that is a precursor to adrenaline. This neurotransmitter, along with adrenaline, plays an important role in the regulation of fear and other negative emotions, increases blood pressure and heart rate, and is also the main neurotransmitter responsible for the body's stress response.

For many, stress is associated with negative emotions, and a happy life under constant stress seems impossible. Does this mean that excess norepinephrine production is a barrier to happiness? Definitely not. Some people find their happiness under constant stress: these include both extreme sports and gambling fans and those for whom the main joy in life is constant work.

Gamma-aminobutyric acid (abbreviated as GABA), the main inhibitory ("inhibitory") neurotransmitter, whose main function is to reduce nervous excitability, also helps control the stress response. GABA receptors are affected by benzodiazepines, psychoactive substances that have anti-anxiety and sedative effects. Benzodiazepines are found in many drugs prescribed for the treatment of anxiety and panic disorders.

More recently, in 2012, the Swedish scientist Hugo Löwheim proposed A new three-dimensional model for emotions and monoamine neurotransmitters. a three-dimensional model of the relationship between the combined action of three monoamines - dopamine, serotonin and norepinephrine - and the manifestation of emotions, called the "emotional cube". According to this model, joy and satisfaction are caused by high levels of dopamine and serotonin and low levels of norepinephrine, while feelings of anxiety and sadness, on the contrary, are caused by high levels of norepinephrine and low levels of the other two. However, in order for a person to experience excitement or excitement, all three monoamines must be produced in large quantities.

Chemistry and will

Different psychoactive substances affect the release of different emotional mediators: for example, cocaine affects the metabolism of dopamine, serotonin and norepinephrine, and nicotine can take part in the metabolism of dopamine. The effects of these substances, however, are short-lived, dangerous and are known to lead to addiction.

However, there are also less radical ways of directly affecting receptors associated with the work of various neurotransmitters. Exercise, for example, enhances Effects of exercise and physical activity on depression. the action of β-endorphins, thereby enhancing mood.

Increased physical activity can even serve as a good prevention of depression.

Areas of the brain containing dopaminergic neurons are activated Intensely pleasurable responses to music correlate with activity in brain regions implicated in reward and emotion. for example, for people who enjoy listening to music.

Today we can say with confidence that those branches of the cognitive sciences that are responsible for the study of complex emotional states (and happiness belongs to them) are still in the process of development. Many psychologists, in particular Oxford University professor Morten Kringelbach, try The Functional Neuroanatomy of Pleasure and Happiness. trace the systematic connection between receiving pleasure and happiness and identify neural correlates responsible for a happy life and good mood.

Kringelbach and his colleague, American psychologist Kent Berridge, distinguish three components of the work of the reward system: "liking", which is responsible for the objective, "chemical" response of a person to a stimulus; Wanting, which is responsible for the volitional effort of a person to receive an incentive; and "learning", which is responsible for building associations associated with receiving a stimulus.

The "inclination" to receive a stimulus, being satisfied, provides us with pleasure, but pleasure alone is not enough for happiness. The “desire” of the stimulus provides motivation to receive it, that is, this component brings a goal into our life, but only “desire”, without being restrained by anything, leads to dependence on the incentive. Learning links these two components and encourages us to find ways to have fun again.

Happiness, according to Kringelbach and Berridge, boils down to a balance of three components: inclination, desire, and learning.

However, how to achieve this balance, scientists do not write.:(Thus, modern neuroscience can only give us an idea of one component of happiness - a positive emotional response to a stimulus. The second component - a sense of the meaningfulness of what is happening, the presence of a goal in life - is a rather philosophical question and at the moment is beyond the scope of systematic objective study.