Mood disorders, formerly known as affective psychoses, are a group of psychiatric disorders characterized by significant and persistent elevations or depressions of mood (emotions). It is a group of psychiatric disorders characterized by significant and persistent elevation or depression of mood (emotion), often accompanied by corresponding changes in thinking and behavior. The manifestations of mood disorders are highly variable, ranging from a milder reaction to a negative life event to a severe relapsing or even chronic disabling disorder. In severe cases, psychotic symptoms such as hallucinations and delusions may occur. They are often recurrent, with most remitting and a few remaining symptoms or becoming chronic. The first onset of this type of mental disorder is mostly between 16 and 30 years of age, and the onset is rare before 15 years of age and after 60 years of age. The age of onset of mania is generally earlier than that of depression, and women are earlier than men. The prevalence of depression is high in women, but the suicide rate is higher in men with depression. Some onset of mood disorders are related to stressful events or life situations. Acute or subacute onset of mania is more frequent in late spring and early summer, while the onset of depression is mostly seen in autumn and winter. Some female patients have episodes related to the menstrual cycle or are aggravated during menstruation. Clinically, there are four types of depressive episodes, manic episodes, bipolar disorder and persistent mood disorder. The core symptoms of depression include depressed mood or mood, lack of interest, and loss of pleasure, which are the key symptoms of depression, and at least 1 of these 3 symptoms should be included when diagnosing a depressive state. Psychological symptom cluster: Depressive episodes contain many psychological symptoms, which can be divided into psychological concomitant symptoms (anxiety, self-blame, psychotic symptoms, cognitive symptoms, and suicidal ideation and behavior, self-knowledge, etc.) and psychomotor symptoms (psychomotor arousal and psychomotor agitation, etc.). Somatic symptom clusters: sleep disturbances (insomnia is the most common), appetite disturbances, hypogonadism, loss of energy, non-specific somatic symptoms such as pain, peripheral discomfort, autonomic dysfunction, etc. The clinical manifestations of depressive episodes can vary significantly among individuals, and atypical presentations are particularly common in adolescent patients. In some cases, changes in mood may also be masked by irritability, alcohol abuse, dramatic behavior, or pre-existing fearful obsessive-compulsive symptoms or hypochondriacal notions. Nevertheless, certain symptoms are important for the diagnosis of depressive episodes, such as loss of interest and pleasure in personal hobbies that are normally experienced as pleasurable; lack of emotional response to normally pleasant situations; waking up 2 h or more earlier than usual; increased depression in the morning; definite psychomotor retardation or agitation; significant loss of appetite; weight loss of 5% or more than 1 month ago; and significant decrease in sexual desire. All should be highly noted. Manic episodes generally have the so-called “three high” symptoms, i.e., high emotion, racing thought and enhanced volitional behavior. High emotion or irritability, which is the main primary symptom of manic state, is often manifested as relaxed, cheerful, enthusiastic, optimistic, and carefree. This kind of emotional reaction is vivid and vivid, coordinated with the inner experience and the surrounding environment, with a certain infectious power, and may not be regarded as abnormal when the symptoms are light, but those who understand him/her can see the abnormality of this performance. Some patients can also be predominantly irritable, often lashing out over trivial matters, especially when accused of arrogance or unrealistic ideas, and behaving as if they cannot hear a single opposing opinion, or in severe cases, can show destructive or aggressive behavior. Patients are often pleasant in the early stages of the disease and become irritable in the later stages, and some patients (at the beginning of the disease) may also experience transient emotional depression or anxiety. The patient’s speech increases and he/she feels that the speed of his/her speech cannot keep up with the speed of his/her thought, and sometimes he/she may have phonological or ideological associations. Inattentiveness may occur, often shifting with the situation. On the basis of the high state of mind can show conceited speech, mostly over-evaluating themselves, appearing to feel good about themselves, exaggerating their words, talking without boundaries, believing that they are exceptionally smart, talented, capable, coming from a famous family with a prominent position of power and wealth, and even reaching the level of delusion. Sometimes the experience of victimization or delusion can be based on exaggeration, but its content is usually not absurd and its duration is relatively short. Hallucinations are less common. Enhanced volitional behavior: i.e., coordinated psychomotor arousal. The internal experience and behavior, and the behavioral response and the external environment are more uniform. In contrast to psychomotor retardation, the patient is more active and busy. The patient likes to socialize and enjoys the company of others, actively interacting with people and getting to know them as soon as they meet. The patient likes to make jokes or pranks, to be nosy, and to hold a good injustice. But the work is not done, although they feel that everything can be done, the brain is very bright, but because of the inability to focus on a certain thing, and therefore not enough to achieve things or even to fail. Lack of thoughtfulness in doing things, sometimes getting into trouble everywhere. Has a wide range of interests but is unpredictable. Helpful, but tend to start but not finish. Behaves recklessly without regard to the consequences, such as sometimes buying and treating people indiscriminately. The patient is reckless and not well thought out, and the behavior is risky. Accompanying symptoms: Manic episode patients often need less sleep due to increased activity. The patient is running around all day long and does not know how to get tired. Due to excessive physical exertion, the diet can be significantly increased, and some patients have uncontrolled diet, overeating or gluttony. Sometimes, because of the inability to drink, eat and sleep normally, the wasting is obvious, and even can fail and die, especially in elderly or frail patients. Patients with mild mania often wear heavy makeup, especially like brightly colored clothing. Some patients are hypersexualized and may occasionally engage in spur-of-the-moment sexual behavior. Sometimes they may be overly affectionate, hugging and kissing in inappropriate situations without regard to the feelings of others. Depressed patients may maintain some self-awareness, while manic patients generally have incomplete self-awareness. Several forms of manic episodes: Typical manic episodes are characterized by high emotions and pleasant feelings as the main symptom, which is the opposite of depression and has the clinical state of the so-called “three highs”. In some variations of manic state, irritability is the main symptom; delirious mania is an extreme form of manic state, and the patient is overexhausted after a period of manic episodes resulting in impaired consciousness; mixed episodes are accompanied by depressive symptoms during manic episodes, and manic and depressive symptoms can appear simultaneously or alternately within a period of time. Manic episodes with psychotic symptoms and depressive episodes. Mania with psychotic symptoms is a severe manic subtype of mania. Self-evaluation is exaggerated and can reach delusional levels. Irritability and paranoia can develop into delusions of victimization, severe and persistent excitement can lead to aggressive or violent behavior, and neglect of diet and personal hygiene can result in a dangerous state of dehydration and self-neglect. Depression with psychotic symptoms is a severe subtype of depression. Low self-esteem and self-blame can reach the delusional level. Bipolar disorder is characterized by recurrent (at least 2) episodes of markedly disturbed mood and activity levels, with disturbances sometimes manifesting as elevated mood, increased energy and activity (mania or hypomania) and sometimes as depressed mood, decreased energy and activity (depression and mild depression). The interictal period usually resolves or largely resolves. However, it should be noted that it is not uncommon for a depressed state of mind to be accompanied by hyperactivity and verbal urgency for several days to weeks, as well as for a manic state of mind and exaggerated states to be accompanied by agitation, decreased energy and initiative. Depressive symptoms and hypomanic or manic symptoms can also change rapidly or even vary from day to day. The diagnosis of mixed bipolar disorder should be made if both sets of symptoms are prominent most of the time during the current episode of illness and if the episode lasts at least 2 weeks.