For a first-year psychology student, the concepts and terms used during the practice of psychology may sound strange . There are many authors who, throughout more than two centuries of life, have been building up the knowledge of what we know today as the science of behaviour and mental processes.

Thus, psychologists and experimenters have been building a series of new words that are part of the slang of mental health professionals. Concepts that have even come to be used not only by therapists but also in common language.

Psychological dictionary: from A to Z

In this article we are going to review more than 200 terms, theories, disorders and authors that you should know if you are going to be a psychologist. From A to Z.



It refers to the presence of powerlessness and unwillingness to act in order to achieve a desired goal. It can be considered the highest degree of apathy.


Tendency to act or think in a certain way with respect to a specific phenomenon, situation or stimulus, derived from experience or the transmission of specific points of view with respect to that reality.


Phobia or pathological and irrational fear of flying.


Difficulty or absence of the ability to communicate effectively in an oral manner These are language disorders produced by damage to the brain areas linked to this ability. Aspects such as verbal fluency, comprehension, imitation or articulation may be affected.


Failure or alteration in the recognition of some type of stimulation. The stimulus is perceived through the senses, but a specific part or aspect of the stimulus is not recognized or not recognized at all. It can occur in any sensory mode.


High intensity, irrational fear or phobia of being or remaining in places or situations where escape or help is not possible or difficult in case of need, such as places where large numbers of people gather. It is often identified with, but not limited to, fear of open spaces.


Impoverishment and slowing down of thought. Altered ability to formulate logical and connected thoughts, as well as to build a coherent discourse. Blockages are often present.


Perceptive deception in which a stimulus is perceived that does not exist in the external environment, generally being convinced by the subject who perceives it of its veracity. They can be of any sensory modality and be linked or not to certain stimuli.

Negative hallucination

Perceptive deception in which the subject is not able to perceive a stimulus that does exist in the real world. For example, he is not able to detect his image in a mirror. Despite this, in many cases the behavior is altered as if the individual were aware of the existence of the stimulus in question.

Antegrade Amnesia

Inability to encode and record new information in memory

Retrograde amnesia

Inability to remember past events, of greater or lesser severity.

Dissociative Amnesia

Amnesia of psychic origin caused by the experience of a traumatic or highly stressful event It is a retrograde amnesia, generally limited to the autobiographical.


Temporary absence or elimination of the ability to perceive pain


Temporary absence or elimination of sensory perception It can refer to the type of product used to produce it.


Absence or diminished presence of the ability to feel joy or pleasure, even in the face of stimulation previously considered pleasant.


Loss of appetite, which can be caused by many different circumstances

Anorexia nervosa

Disorder characterized by the refusal of the sufferer to maintain a minimum body weight, presenting fear of gaining weight and maintaining an alteration of the perception of one’s own body image. In order to reduce the weight, people eat less or do not eat enough, in some cases resorting to compensatory behaviors such as vomiting or strict diets. A restrictive and a purgative subtype can be found.


A state of emotional discomfort or suffering in anticipation of possible future aversive stimulation, which generates cognitive, physiological and behavioural reactions.


A substance with psychoactive effects capable of helping to regulate, manage or eliminate a state of anxiety or distress.


A substance with psychoactive effects whose action is capable of combating states of emotional distress such as those of depressive states.


Lack of motivation to act, absence or diminished presence of interest


Difficulty or absence of the ability to perform and coordinate sequential movements


Maximum degree of diminished attention span. Absence of attention and the ability to mobilize it.


Ability to effectively and skillfully perform a certain type of action.


Absence of energy. Fatigue and a state of weakness that makes it difficult to carry out activities.


According to Albert Bandura’s theory, self-confidence refers to the perception of one’s ability to achieve certain goals and carry out various actions successfully. Also known as self-efficacy.


A set of thoughts and beliefs about one’s own self that each individual has. It’s the concept or image that each one has of himself.


It is a term used in psychology to designate the consideration and esteem that each individual professes towards his or her own person. It is the valuation that a person makes of himself based on his self-concept.


A set of internal vocalizations directed to oneself that are used to guide one’s behavior through sequences of instructions.


Bandura, Albert

Albert Bandura is one of the most influential and recognized psychologists, having been president of the American Psychological Association. His best known studies form the Theory of Social Learning. For this author, behavior can be modified and replicated through the observation of behavior models and their subsequent imitation.


Type of substance derived from barbituric acid that is used mainly as a hypnotic and sedative. Before the advent of benzodiazepines, they were the most widely used type of drug in the fight against anxiety and sleep disorders. Their therapeutic and toxic doses are very close and generate dependence easily, being the overdose relatively simple to achieve and may cause the death of the subject.


Type of substance traditionally used as an anxiolytic. They act mainly through the potentiation of gamma-aminobutyric acid, which reduces the level of brain activation. They are also used in the treatment of insomnia and other problems.


Bipolar disorder is a mood disorder characterized by a disturbance between manic and depressive states. It can be type one, in which at least one manic episode has occurred, or type two, in which there has been no manic episode but a hypomanic episode and one or more depressive episodes.



Bulimia nervosa

An eating disorder characterized by the presence of binge eating, in which control of intake is lost, followed by feelings of guilt and compensatory behaviors performed in order not to gain weight, such as the induction of vomiting. Self-assessment is significantly linked to the appreciation of the body shape. It can be of the purgative or non-purgative type.



Disorder characterized by lack of mobility, waxy flexibility, opposition and negativism, eco-symptoms, mannerisms, perseveration, rigidity, mutism and stupor.


An organ located inside the skull, a central element of the nervous system in most animals, especially vertebrates. Its main function is the direction and management of all the systems that make up the organism. Although the upper part of the brain, the cortex, is technically called the brain, it is generally referred to as the whole of the brain.


A mood disorder characterized by the presence of mood swings between depression (without meeting the criteria for diagnosing major depression) and hypomanic euphoria, persisting continuously for at least two years. These fluctuations and symptoms are less than those of bipolar disorder, and bipolar disorder cannot be diagnosed.


A psychology paradigm focused on the understanding and study of the cognitive processes that govern and regulate human behavior based on a scientific and reason-based methodology.


The most profound state of loss of consciousness, in which the subject does not respond to any type of stimulation and which is due to a serious injury or alteration of brain function. Despite this, there is brain activity, so the person is still alive even though he or she may need breathing and artificial life support. The prognosis is highly variable depending on what has caused this condition.


How to act in a certain situation. It is often used as a synonym for conduct.


A ritualized act performed for the purpose of relieving anxiety generated by a particular thought or act. Its performance does not imply a resolution of the problem, but in fact feeds back into it, so that the subject tends to repeat it in order to produce temporary relief.


Any act or action performed by an agency, usually intentionally and voluntarily.


One of the main paradigms of psychology. It is based on the premise of focusing research exclusively on empirical data demonstrable through experience, using the scientific method. It mainly analyzes the only directly observable correlate of the psyche, behavior. This is explained by the capture of the properties of the stimuli and the emission of the responses to these, as well as the association between stimuli and responses. It can be modified by learning, either from the stimulation itself or from the reinforcement or punishment of behaviour.


Projection of a set of feelings, reactions and emotions by the therapist on his patient, generated on the basis of the existing link in the therapeutic relationship.


Violent, abrupt and involuntary contractions of the musculature, generally generated by an alteration of the brain activity. This is one of the most visible and well-known symptoms of epileptic seizures.

Cerebral Cortex

A group of nervous tissue that forms the most external and superior part of the brain and that allows the analysis and integration of the different information coming from the environment, as well as the acquisition and realization of different abilities and aptitudes such as speech, abstract thinking, intelligence or the ability to regulate behavior.


Phobia or irrational fear of clowns, cause unknown.


Anxiety and distress felt by a subject due to a strong desire to consume a substance.

Corpus Callosum

A structure composed mainly of the axons of a large number of neurons, which keeps the two cerebral hemispheres interconnected and allows the transmission and integration of information from both.



Alteration of the content of thought. A certain idea or belief is presented that is experienced as real and is characterized by being of great intensity, irrational and resistant to change despite evidence to the contrary.


State of altered level of consciousness of variable severity, sudden onset and short duration that causes a decrease in intellectual capacities and the presence of possible alterations in attention, memory, speech, perception and motor skills. Its origin is found in an illness, intoxication or sensory deprivation

Delirium Tremens

Acute and life-threatening confusional condition resulting from the abrupt cessation of alcohol consumption in alcohol-dependent persons. This is one of the most serious and dangerous forms of withdrawal syndrome. Alterations in the level of consciousness, visual hallucinations, feverish states, convulsions, stupor and emotional lability are frequent.


Neurodegenerative disorder, generally of biological origin, which causes a progressive deterioration of different cognitive abilities such as memory, speech, movement sequencing or reasoning skills. It differs from delirium in the progressive deterioration of mental capacities and the absence of alterations in consciousness.


Mood disorder characterized by a sad and/or irritable mood, the presence of anhedonia and other symptoms such as hopelessness, feelings of helplessness, decreased attention span, and perception of reality from a negative perspective regarding the world, oneself, and one’s future.


A pattern of language in which there is no common thread in the speech. There is a loss of associations, building up sentences that are unrelated to each other and bringing them together with no apparent meaning.


Feeling of not being in one’s own body, feeling the body and one’s own mind as something strange.


A defence mechanism based on the person projecting into a given situation, stimulus or person the feelings and reactions that other situations, stimuli or persons have provoked, without there being a link between the two elements.


Sense of unreality with respect to what one is experiencing. Things, surroundings and/or situations are perceived as strange and unreal.

Intellectual disability

Presence of more or less severe limitations in the interaction and adaptation to the environment due to the presence of a lower than expected intellectual capacity by age and level of mature development of the subject.


Neurological disorder that generates involuntary and uncontrolled movements, usually in the facial muscles.


A speech disorder in which there are difficulties in articulating phonemes, resulting in substitutions of one phoneme for another, distortions, additions or even omissions.


Also called stuttering, it refers to a speech flow disorder in which the subject suffers a blockage in the form of a spasm that prevents or interrupts the formation of words. It is often accompanied by embarrassment and avoidance of public speaking.


Alteration of the mental capacities that implies a partial or total rupture between different aspects of the psyche, having a separation between the integrated self and some of the different aspects or capacities of the mind. It is frequent in the face of traumatic events. Concrete examples may be dissociative amnesia or multiple personality disorder.


Presence of pain during, after or even before sex. It may cause avoidance of not only sexual but also emotional relationships


A mood disorder characterized by low positive affect and low energy levels that occur continuously over time. A sad mood is maintained for at least two years on an almost daily basis, with frequent increases or decreases in appetite, sleep problems, low self-esteem, and feelings of hopelessness and helplessness, although less severe than depression.


A substance which, when introduced into the body, may alter one or more of the body’s functions. If we talk about psychoactive substances, drugs are characterized by producing alterations in the brain’s functioning and can cause satisfactory sensations for the consumer, although their prolonged consumption tends to make the organism get used to them and generate tolerance.


Ellis, Albert

Cognitive psychologist of great importance worldwide. Creator of Rational Emotive Therapy, who considered that emotional states are generated by the interpretation of the phenomena we live. Therefore, it is necessary to provoke a change in this interpretation if we want to achieve a change in the patient’s emotional state.


Ability to perceive, detect and share a person’s mood and/or perspective, knowing how to put oneself in their place.


Phobia or intense and irrational fear of blushing in public and having others notice. Linked to the fear of being judged by others.


Pathological and irrational fear or phobia of showing up at one’s workplace. It does not necessarily prevent the inability to maintain an occupation, but it makes it more difficult. The causes may be multiple.

Perceptual Excision

Disintegration and separation into different elements of aspects of the same stimulus, which are captured separately. For example, sound and image, or colour and shape, are captured separately.


Psychotic-type disorder characterized by the presence of positive symptoms such as hallucinations and delusions and/or negative symptoms such as impoverishment and language impairment, difficulties in maintaining attention. One of the best known symptoms is the presence of generally auditory hallucinations. There are several subtypes.


Performance of certain movements, postures or emission of sounds in a repetitive or ritualized way without a specific purpose.


A state of intense physiological activation that is intended to act as a mechanism to deal with a threatening situation. If it is prolonged in time, it can generate fatigue and exhaustion due to the wear and tear caused by the continuous use of energy resources at both the physical and mental levels.


State of altered consciousness from which it is very complex to get out, requiring a very powerful stimulation to do so. It is usually accompanied by immobility and the absence of voluntary movement.


Emotional state considered normative, without major alterations and relatively stable.


Paraphilia characterized by the presence of persistent sexual fantasies and the performance of acts consisting of exhibiting the genitals in public before unknown persons, with the observation of the surprise or the reaction of others being the reason for the subject’s excitement.


A type of therapy that is based on confronting the patient with what he or she fears or causes anxiety, so that he or she is able to cope with it and progressively decrease the level of fear it causes. It is usually employed on the basis of a hierarchy according to what the patient’s level of anxiety is, advancing more or less gradually.


A personality trait that is characterized by a focus on the outside world, with a tendency to relate to others and interact with the environment.



Tendency to the presence of recurrent sexual fantasies linked to the use of non-animate objects. which causes discomfort or deterioration in some vital area of the subject who suffers it. This is a type of paraphilia.


Taste, preference or fondness for certain situations or stimuli, which one tends to approach. It is considered the opposite of phobia.


Phobia of falling in love. Fear of bonding, in many cases derived from fear of abandonment or humiliation.


Irrational, disproportionate, and high intensity fear of a particular stimulus or situation that causes behavioral avoidance (or desire for avoidance) of the stimulus. The feared stimulus generates anxiety and distress. The existence of a phobia can cause an alteration in the habitual life of the individual who suffers it.

Freud, Sigmund

Father of psychoanalysis. This Viennese doctor established psychoanalysis as a method of studying behaviour, explaining the psyche and treating mental problems. He focused his theory on the presence of conflicts between different psychic structures and the repression of unconscious drives and instincts. He considered that the psyche was fundamentally directed by sexual drive or libido, elaborating different theories regarding mental functioning and psychosexual development.


Paraphilia characterized by the continuous presence of fantasies and sexual impulses linked to the idea of rubbing up against unknown people and against their will, impulses that have either been carried out or generate discomfort in the subject.



Disorder caused by neurological alterations and injuries in which the affected person has severe difficulties or is unable to capture half of the hemicamp, not being aware of part of his perception and unable to orient himself, respond or act on the opposite side of the brain injury.



Distorted perception or interpretation of an existing but ambiguous real stimulus.


Ability of a subject to alter the behavior or thought of another.


Personality trait characterized by a focus on the inner world and one’s own mental processes, requiring less activation from the environment.


Locus of control

The individual’s perception of the causality of the different phenomena that occur to him. The subject attributes successes and failures to different types of causes, which may be stable or unstable, global or particular, internal or external. This attribution is linked to the attitude that each person takes before the different events and even is related largely to self-concept and self-esteem.


Ability to guide and direct the behaviour of others towards a specific objective, being able to manage the actions of other people, establishing objectives and motivating towards their achievement.


Disorder characterized by the presence of uncontrolled impulse and the need to play different types of games of chance. The subject is incapable of resisting the impulse, using it as a method to fight the discomfort and producing an addiction that alters the vital functioning of the subject and his environment.



Expansive and highly active mood, with accelerated thinking and speech, high impulsivity that can lead to irritability and hostility. Characteristic of the consumption of certain substances or of disorders such as bipolar.


Type of therapy based on deferred learning in which one or several subjects act as models recreating a certain situation, so that the patient observes how to perform certain actions or behaviors and then be able to carry them out. There are many different types of modelling depending on the type of model, the level of participation of the subject or the means used.


Method by which we try to achieve the establishment of a certain behavior through the realization of behaviors increasingly closer to the desired, establishing intermediate steps to achieve that will be reinforced.



Type of cell that forms the basic unit of the nervous system, whose interconnection allows the transmission of electrochemical impulses through the body in order to manage the different systems that make it up.


A psychological trait that refers to an individual’s level of emotional stability or instability. Neurotic subjects have a labile emotionality, characterized by elevated levels of anxiety and tension and the rapid change from a positive to a negative emotional state.



A state of altered consciousness in which it is difficult to capture the individual’s attention, being continually distracted and there may be perceptual alterations. The subject is disoriented and confused if taken out of this state.


Repetitive and uncontrolled thinking that appears spontaneously in the mind and proceeds to repeat itself insistently, being perceived as inadequate and highly distressing. This thought is lived as if it were our own despite not being controlled, and it is usually tried to be avoided through various mechanisms. This is the main core of obsessive-compulsive disorder.



Presence of persistent fantasies of an excitatory nature towards atypical objects of desire that usually include non-human or non-consensual subjects, objects, or pain, which produce discomfort and suffering and affect the habitual functioning of the person who suffers from it or of third parties.


Perceptual phenomenon through which a person perceives a recognizable pattern or shape to an ambiguous or ill-defined stimulus, such as shapes in clouds or perceiving the shape of a face in smoke or spots on a wall. This is not pathological.


Sub-type of paraphilia in which the object of sexual attraction of a subject is a minor child, the subject being at least sixteen years old and at least five years older than the object of desire.


Defense mechanism in which the subject identifies characteristics of other individuals, groups, objects or entities.


Also known as psychological pregnancy. This is a type of dissociative disorder that causes the symptoms of pregnancy without actually occurring.


Symbol commonly associated with psychology.


Substance with psychoactive activating effects, which cause an increase or acceleration of the nervous system.


Paradigm of psychology focused on the unconscious and the existence of conflicts between instincts and their external expression. It focuses largely on the deep part of the psyche and its analysis, working with symbolic elements. It also focuses on patients’ past experiences, especially those that occurred during development. Psychoanalysis is considered a theoretical framework, a research technique and a therapeutic method.


Substance with psychoactive effects that generates an alteration in the functioning of the nervous system, producing different consequences and being able to alter the perception.


It refers to something whose origin or cause is psychological and not organic.


Type of depressant substance, which causes a slowdown or decrease in the activity of the nervous system.


Individual characterized by a lack of empathy, superficial charm, low responsibility and cordiality and difficulties in establishing long-term goals, giving priority to the immediate satisfaction of one’s own needs even at the expense of others. They tend to present low level of obedience to authority and present antisocial behaviors.

Psychotic, disorder

A type of disorder characterized by the presence of a break or mismatch of the psyche with reality, with unusual behavior observed and frequent hallucinations and delusions.