A representation of something else using principles that allow you to map properties of the model onto theoretically-selected properties of that something. By their very nature, all models are selective, and the selection (the ‘target system’ is determined by the purpose of the modeller and the materials available. Whatever they represent is important and they …
Author Archives: Brian Hopkins
Mobile conjugate reinforcement
An operant conditioning procedure in which infants aged between 2- and 6-months learn to kick a foot in order to produce movement in an overhead mobile (see video for a depiction of the procedure). Stemming from an ongoing program of research on infant learning and memory carried out by Carolyn Rovee-Collier and colleagues since the …
Mitosis
The division of a cell to form two daughter cells, each having a nucleus containing the same number and kind of chromosomes as the mother cell. Each chromosome divides lengthwise into two chromatids that separate and form into the chromosomes of the resulting daughter cells. The process consists of four phases: prophase, metaphase, anaphase and telophase, …
Mixed-effects models
A set of statistical techniques used to estimate parameters about 1. fixed effects based on groups (i.e., mean differences and regressions) as well as 2. random effects based on individual differences (i.e., variance and covariances). A fixed effectamounts to something that remains the same if an experiment is repeated (e.g.,age, gender). A random effect issome entity than …
Missing at random (MAR)
The assumption that the sub-set of persons for whom data are not measured (i.e., incomplete or missing), data can be indicated by scores on variables that are measured (i.e., complete). The MAR assumption is different than the traditional assumption of ‘missing completely at random’ (MCAR), and it permits a correction for the bias due to …
Mitochondria
Minute, rod-shaped or granular bodies, about 1/4 to 3¬µm in length or diameter that occur in the cytoplasm of most cells responsible for aerobic respiration that breaks down food in the presence of oxygen and carbon dioxide, leading to the generation of energy. Thus, they are the ‘powerhouses’ of a cell. They contain many of …
Mirror neurons
These neurons were discovered in a particular region (called F5) of the monkey’s brain in the mid-1990s by Giacomo Rizzolati and his research team at the University of Parma. The special property of mirror neurons is that they are activated both by the observation and the execution of a specific action. For example, mirror neurons …
Miniamata disease
A form of mercury poisoning from ingesting methyl mercury in contaminated fish that led to 43 deaths in the Japanese coastal town of Miniamata during 1953-1956. The source of the mercury was traced to an effluent containing mercuric sulphate from a local PVC factory. Signs include numbness, difficulty in controlling the limbs, and impaired speech …
Minor neurological dysfunction (MND)
The presence of mild impairments observed during a neurological examination such as mild problems in muscle tone regulation and with co-ordination or fine manipulation. See Developmental coordination disorder (DCD), Impairment, Muscle tone, Neurodevelopmental disorder, Neurological ‘soft’ signs
Mind reading
The ability to infer what someone else is thinking or feeling. Also known as adopting the ‘intentional stance’. It is not the same as mind sight (‘or empathic accuracy), which is a seemingly magical ability to predict someone’s thoughts from their words, emotions and ‘body language’. Nor does have anything to do with the study …