25 of the Psychology glossary’s terms, each with the part of the syllabus where you first meet it.
A study in which the independent variable changes naturally, through an event the researcher did not cause or control, and the researcher measures its effect on behaviour.
An observation of behaviour in the setting where it normally occurs, such as a home, playground or street, with no interference from the researcher.
The debate about the relative contribution of inherited factors (nature) and environmental factors (nurture) to behaviour, now usually replaced by the study of how the two interact.
Brief, spontaneous negative thoughts about the self, the world or the future that arise in everyday situations, feel believable and are rarely questioned.
A control process in which a rise in a hormone’s level acts back on the hypothalamus and pituitary gland to reduce further release, keeping the level stable.
Strengthening a behaviour because it removes, ends or avoids an unpleasant stimulus, such as pain, anxiety or a loud noise.
An organised set of negative beliefs about the self, formed through early experience, that biases how self-relevant information is processed and creates vulnerability to depression.
A diagnosis of “weakness of the nerves”, with fatigue, headaches, poor concentration and poor sleep, widely used in China for distress often classed in the West as depression or anxiety.
The formation of new neurons; in adult mammals it occurs in only a few regions, such as part of the hippocampus, and how much it happens in adult humans is debated.
A nerve cell that carries information through the nervous system, electrically along its own length and chemically to other cells.
The ability of the brain to change its structure and function in response to experience, learning or injury, throughout life.
The process by which a neuron passes a signal to another cell: an action potential causes release of a neurotransmitter that crosses the synaptic gap and binds to receptors.
A chemical messenger released by a neuron into the synaptic gap that binds to receptors on a neighbouring cell and makes it more or less likely to fire.
A stimulus that, before conditioning, does not trigger the response being studied, apart from perhaps a brief orienting response.
A treatment for tobacco addiction that supplies nicotine through patches, gum, lozenges or sprays without tobacco smoke, reducing withdrawal and cravings while the person stops smoking.
Data in the form of separate, unordered categories (such as attachment type or country), summarised by counting how many cases fall into each category.
An observation in which the researcher watches the group from outside and does not take part in its activities.
A sampling bias that arises when the people who do not respond to a survey differ systematically from those who do, so the results misrepresent the target population.
The sending of information without words, through facial expression, eye contact, gesture, posture, touch, use of space and tone of voice.
A chemical messenger that acts as a neurotransmitter in the brain and as a hormone released by the adrenal glands, increasing arousal, alertness and the body’s readiness for action.
A symmetrical, bell-shaped distribution in which most scores cluster around the centre, the mean, median and mode are equal, and about 68% of scores lie within one standard deviation of the mean.
A change to the way choices are presented (choice architecture) that steers people towards a particular option, such as a healthier food, without forbidding alternatives or significantly changing their cost.
A prediction that there will be no effect of the independent variable on the dependent variable, or no relationship between variables, and that any difference found is due to chance.
The shift in a population’s diet and activity from traditional foods and active work towards processed, energy-dense foods, sugary drinks and sedentary lives, which accompanies economic development and urbanisation.