WACE Psychology key terms

A chemical messenger released from the end of a neuron that travels across a tiny gap to influence whether the next neuron fires. Different transmitters are linked to mood, movement, sleep and reward.

The small junction between two neurons, or between a neuron and a muscle or gland, where signals are passed chemically. It includes the sending terminal, the gap and the receiving membrane.

The process by which a sending neuron absorbs its released neurotransmitter back from the synapse, ending its effect. Many antidepressant drugs work by slowing this process so the transmitter stays active longer.

A brief electrical impulse that travels along a neuron's axon when stimulation passes a threshold. It is an all-or-nothing event, so stronger messages come from more frequent firing rather than bigger impulses.

The branch of the nervous system controlling involuntary body functions such as heart rate, digestion and sweating. It has sympathetic and parasympathetic divisions that broadly speed up or calm the body.

A rapid bodily reaction to a perceived threat, preparing a person to confront or escape danger. Heart rate, breathing and blood sugar rise while digestion slows, largely driven by adrenaline and sympathetic activity.

A hormone released by the adrenal glands during stress that raises blood sugar and helps the body sustain effort. Prolonged high levels are associated with impaired immune function and memory difficulties.

A small almond-shaped structure deep in the brain involved in detecting threat and generating emotional responses, especially fear. It attaches emotional significance to sensory information and helps form emotional memories.

A seahorse-shaped brain structure essential for forming new long-term declarative memories and for spatial navigation. Damage to it typically leaves older memories intact while blocking new ones.

The brain's ability to reorganise its connections and structure in response to experience, learning or injury. It underlies skill acquisition, recovery after stroke and some effects of therapy.

The first stage of memory, in which incoming information is converted into a form the brain can store. Encoding is more effective when material is processed for meaning rather than only for sound or appearance.

The process of bringing stored information back into conscious awareness. Retrieval success depends on cues and on how well the information was encoded and organised in the first place.

A limited-capacity system that holds and manipulates information for short periods while a task is being carried out. It supports reasoning, comprehension and mental arithmetic rather than simple passive storage.

A mental framework built from past experience that organises knowledge and guides how new information is interpreted and remembered. Schemas speed up processing but can distort recall toward expectations.

A quick mental shortcut or rule of thumb that simplifies judgement. Heuristics are often efficient but can produce predictable biases, such as overestimating vivid or easily recalled events.

Judging the likelihood or frequency of an event by how easily examples come to mind. Vivid, recent or heavily reported events therefore feel more common than they actually are.

The tendency to seek out, notice and remember information that supports existing beliefs while overlooking or discounting contradictory evidence. It affects everyday reasoning and the interpretation of research.

Learning in which a neutral stimulus comes to trigger a response after being repeatedly paired with a stimulus that already produces that response. The response is involuntary and often emotional or physiological.

Learning in which the consequences of a behaviour change how often that behaviour occurs. Reinforcement increases behaviour, punishment decreases it, and timing and schedules strongly influence the result.

Adding a desirable consequence after a behaviour, which makes that behaviour more likely to happen again. Praise, tokens or rewards are typical examples when they strengthen the response.

The gradual weakening and disappearance of a learned response when the reinforcement or conditioned stimulus pairing stops. Extinction is not erasure; the response can return after a delay or renewed exposure.

In Piaget's theory, interpreting new experiences using existing mental frameworks without changing them. A child who calls a zebra a horse is fitting new information into an existing animal category.

In Piaget's theory, altering or creating mental frameworks to fit new experiences that do not match existing ones. It produces cognitive change and complements assimilation in driving development.

The understanding that objects continue to exist even when they are out of sight. It typically develops during infancy and is tested by observing whether a baby searches for a hidden toy.

The understanding that quantity, mass or volume stays the same despite changes in appearance or arrangement. It usually develops in middle childhood, so younger children judge by the most striking feature.

An enduring emotional bond between an infant and a caregiver that provides comfort and a secure base for exploration. Its quality is often assessed through responses to separation and reunion.

A structured observational procedure in which a young child experiences brief separations and reunions with a caregiver in an unfamiliar room. Behaviour patterns are used to classify attachment style.

A limited window in development during which a particular capacity must be acquired, or it will not develop normally. Language and some visual abilities are often cited as examples.

Shared, often unwritten expectations about how members of a group should behave in given situations. They guide conduct through approval and disapproval rather than formal laws.

Changing one's behaviour or stated beliefs to match those of a group, often because of real or imagined pressure. It can stem from wanting to be accepted or from believing the group is better informed.

Following a direct instruction from a person in authority. Obedience differs from conformity because it involves an explicit command rather than pressure to match peers.

The finding that people are less likely to help someone in need when others are present. Diffusion of responsibility and uncertainty about what is happening help explain the pattern.

The process of explaining the causes of one's own or another person's behaviour. People tend to overemphasise personality and underestimate situations when judging others.

A generalised belief about the characteristics of members of a social group. Stereotypes simplify social perception and can become harmful when they drive prejudice or discrimination.

A negative attitude or feeling toward a group and its members, formed without adequate evidence. It is an attitude, whereas discrimination refers to behaviour that disadvantages people.

The factor an experimenter deliberately manipulates or selects in order to observe its effect. It defines the conditions being compared and is not dependent on what participants do.

The outcome measure that is recorded to see whether the manipulation had an effect. It must be operationalised clearly so that it can be observed and measured consistently.

A comparison group that does not receive the treatment or condition under investigation, or receives a neutral version of it. It provides a baseline against which the experimental group is judged.

Assigning participants to conditions by chance so that each person has an equal opportunity to be placed in any group. This reduces systematic differences between groups before treatment begins.

The consistency of a measurement or procedure: producing similar results when repeated under the same conditions. It is necessary but not sufficient for validity, since a measure can be consistently wrong.

The extent to which a study or measure assesses what it claims to assess. Internal validity concerns causal conclusions, while external validity concerns generalising findings beyond the sample and setting.

A precise, observable description of how a variable will be measured or manipulated in a particular study. It converts abstract concepts such as stress or aggression into concrete procedures.

Principles researchers must follow to protect participants, including informed consent, confidentiality, the right to withdraw, and minimising harm. Approval by a review board is usually required before data collection.

Gaining participants' voluntary agreement after explaining the study's purpose, procedures, risks and right to withdraw. It protects autonomy and must be obtained before data are collected.

A result unlikely to have occurred by chance alone, conventionally judged against a probability threshold such as five percent. It indicates a probable effect, not necessarily a large or important one.

A system that groups patterns of symptoms into recognised disorders using agreed criteria, such as the DSM. It aids communication and treatment planning but can oversimplify individual experience.

The co-occurrence of two or more disorders in the same person at the same time. It complicates diagnosis and treatment because symptoms may overlap or interact.

An explanation that a disorder emerges when a personal vulnerability, such as genetic risk or a thinking style, is triggered by stressful life events. Neither factor alone is considered sufficient.

A habitual pattern of biased thinking that misrepresents experience, such as catastrophising or all-or-nothing reasoning. Such patterns are targeted in cognitive therapy for anxiety and depression.