Making Sense of the Environment

The limbic system is a neuronal network that mediates emotion and motivation, while also playing a role in learning and memory. The extended neural network is vital to numerous basic psychological functions and plays an invaluable role in processing and responding to environmental stimuli.

Sleep is a reversible phase of diminished responsiveness, motor activity, and metabolism. This process is a complex and dynamic phenomenon, occurring in 4–5 cycles a night, and generally divided into non–rapid eye movement (NREM) sleep and REM sleep stages. NREM sleep, consisting of 3 stages, represents the period of transition from wakefulness, somnolence, and then deep sleep. REM sleep is characterized by rapid irregular eye movement, but with voluntary muscle atonia. The sleep stages and associated disorders are studied through the use of polysomnography, a multimodal test evaluating the brain waves, along with ocular and motor activities. Sleep disorders can be primary (which do not stem from any health problem) or can be attributable to underlying conditions or medications.

Circadian rhythm sleep–wake disorders are a group of conditions marked by recurrent patterns of sleep disruption. These disorders can be due to an alteration of the circadian system (intrinsic) or a misalignment between an individual’s inner circadian rhythm and the environment (extrinsic). The disruption impairs the individual’s daily activities. There are 6 different subtypes, including delayed and advanced sleep–wake phase disorder, irregular and non-24-hour sleep–wake rhythm disorder, shift-work disorder, and jet lag. Diagnosis is generally clinical, but using tools such a sleep diary and actigraphy help in determining the disorder. Management for circadian rhythm sleep–wake disorders involves light therapy, behavioral modification, and pharmacotherapy, such as with melatonin.

Hallucinogen use disorder is defined by the pathologic consumption of hallucinogenic substances that cause perceptual distortions (visual or auditory). Examples include psilocybin (mushrooms), lysergic acid diethylamide (LSD), and phencyclidine (PCP). These drugs are used for their psychedelic effects, i.e., a temporarily altered state of consciousness. Most hallucinogens produce nausea, vomiting, and mild sympathomimetic effects such as tachycardia, hypertension, mydriasis, hyperthermia, and diaphoresis. Although hallucinogens may cause hyperthermia in severe cases, they don’t result in dependence or withdrawal symptoms.

Parasomnias are a pattern of sleep disorders marked by unusual actions, activities, or physiological events that occur during sleep or sleep-wake transitions. Parasomnias are divided into which sleep phase the symptoms occur, either rapid eye movement (REM) or non-REM (NREM). Symptoms may include simple or complex abnormal movements, such as sleep talking, sleepwalking, sleep terrors, and dream enactment, or emotions, dreams, and autonomic activity. Diagnosis involves a thorough history taking from the patient and the partner. In some cases, polysomnography is required, especially if comorbid sleep disorders are suspected. Some conditions resolve over time without any treatment. For those that require intervention, options include lifestyle or risk modifications, different forms of therapy, and medications. Choice of management is affected by patient preferences.

Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychodynamic therapy seeks to bring forward unconscious or repressed thoughts to help address the current behavior. Cognitive-behavioral therapy corrects faulty assumptions and tries to replace maladaptive behavior with healthier alternatives. Psychoeducation provides patients with information about the disorder, including anticipated problems and treatment so that they are able to manage. Other forms include supportive therapy (short-term therapy to help through a life crisis), motivational interviewing (changing maladaptive behaviors by guiding the patient to be the agent of change for themself), interpersonal therapy (focusing on the relationships rather than repressed thoughts), and dialectical behavioral therapy (using a hierarchy of treatment targets, like reduction of suicidal and dangerous behavior). Treatment is offered in different formats (individual, family, couple, or group). The goals vary and can include changing the individual’s behaviors and thoughts, improving relationships, reducing psychiatric symptoms as well as functional impairment, and involving the family to enhance treatment.

Substance use disorders are a significant cause of morbidity and mortality, especially among adolescents and young adults. A substance-related and addictive disorder is the continued use of a substance despite harmful consequences; these include significant impairment to one’s health or relationships or failure to fulfill major responsibilities at work, school, or home because of substance use. There are several individual substance use disorders, and they are linked by their chronicity and the significant impairment they cause. Most substance use disorders have associated intoxication and withdrawal symptoms. Treatment options include pharmacotherapy and behavioral interventions; however, individuals with substance use disorders have frequent relapse/remission as well as low compliance with treatment.

The human brain is a very complex organ, structurally and functionally. Cognition is a term that psychologists use to describe a wide array of different brain processes and activities that include perception, thinking, reasoning, memory, attention and creating new information or ideas. This is however a limited view of cognition as now it became clear that cognition is the product of interplay between all of these components and more.

Learning and the development of memory are processes that cannot be strictly separated from psychology and sociology. Thus, this article deals with the physiology of learning and memory. Topics include understanding the relationship between experience and storage of acquired knowledge, how the brain deals with “useless” knowledge, and how a baby starts to understand its surroundings.

Why do you decide in favor of certain actions and behavior but not of others? To get to the bottom of this question, psychology has developed a number of learning models. Classical and operant conditioning, learning by self-control, and observational learning are important basics that psychotherapy is based on. The following article contains, in addition to all facts about learning, knowledge about memory and language that is relevant for your exams.