Conditions

Depressive disorders encompass several conditions, including disruptive mood dysregulation disorder, major depressive disorder (which includes major depressive episodes), persistent depressive disorder, premenstrual dysphoric disorder, substance / medication-induced depressive disorder, depressive disorder resulting from another medical issue, other specified depressive disorder, and unspecified depressive disorder. A shared characteristic of all these disorders is the existence of a sad, empty, or irritable mood, along with associated changes that significantly impact the individual’s ability to function (for example, somatic and cognitive shifts in major depressive disorder and persistent depressive disorder). The
distinctions among them lie in duration, timing, or presumed causes.

Anxiety disorders encompass conditions characterized by intense fear and anxiety along with associated behavioral issues. Fear represents the emotional reaction to an actual or imagined imminent threat, while anxiety involves expecting potential future dangers. Although these two states overlap, they also have distinct features, with fear typically linked to spikes in autonomic arousal essential for fight or flight responses, immediate danger thoughts, and escape behaviors. In contrast, anxiety is more commonly associated with muscle tension and a heightened state of alertness in preparation for possible threats, leading to cautious or avoidant actions. In some cases, pervasive avoidance behaviors can diminish the intensity of fear or anxiety. Panic attacks are a notable aspect of anxiety disorders, representing a specific type of fear response. However, panic attacks can also occur in other mental health conditions, not just anxiety disorders.

ADHD is a neurodevelopmental disorder characterized by significantly impairing levels of inattention, disorganization, and/or hyperactivity-impulsivity. Inattention and disorganization involve difficulty remaining focused, appearing to not listen, and misplacing essential materials for tasks at levels not typical for one’s age or developmental stage. Hyperactivity-impulsivity includes excessive movement, fidgeting, trouble remaining seated, interrupting others; activities, and an inability to wait, exhibiting symptoms that are excessive for one’s age or developmental level. During childhood, ADHD often co-occurs with disorders commonly referred to as “externalizing disorders,” such as oppositional defiant disorder and conduct disorder. ADHD tends to continue into adulthood, leading to difficulties in social, academic, and occupational areas.

Trauma- and stressor-related disorders include conditions where experiencing a traumatic or stressful event is clearly stated as a diagnostic requirement. These include reactive attachment disorder, disinhibited social engagement disorder, posttraumatic stress disorder (PTSD), acute stress disorder, adjustment disorders, and prolonged grief disorder. The psychological distress that arises after facing a traumatic or stressful situation can vary significantly. In certain instances, symptoms can be effectively interpreted within an anxiety or fear-related framework.

Schizophrenia spectrum and other psychotic disorders include schizophrenia, other psychotic disorders, and schizotypal (personality) disorder. They are defined by abnormalities in one or more of the following five domains: delusions, hallucinations, disorganized thinking (speech), grossly disorganized or abnormal motor behavior (including catatonia), and negative symptoms.

Bipolar I disorder reflects the contemporary interpretation of what was once known as manic-depressive disorder or affective psychosis, as described in the 1800s. The main difference from that original description is that neither psychosis nor the occurrence of a major depressive episode throughout a person’s life is mandatory. Nevertheless, most people who exhibit symptoms that align with a

fully developed manic episode will also undergo major depressive episodes at some point in their lifetime.

Bipolar II disorder necessitates a lifetime occurrence of at least one major depressive episode and at least one hypomanic episode without any history of mania. It is no longer considered a less severe condition than bipolar I disorder, primarily due to the significant impact of depression in bipolar II disorder and because the mood fluctuations experienced by those with bipolar II can lead to considerable difficulties in both work and social environments.

Substance-related disorders include ten different categories of drugs: alcohol; caffeine; cannabis; hallucinogens (with distinct groups for phencyclidine [or similarly acting arylcyclohexylamines] and other hallucinogens); inhalants; opioids; sedatives, hypnotics, or anxiolytics; stimulants (such as amphetamine-type substances, cocaine, and other stimulants); tobacco; and other (or unidentified) substances. These ten categories are not entirely separate. All substances consumed in excessive amounts can directly stimulate brain reward systems, which play a role in reinforcing behaviors and forming memories.