Final consonant devoicing

A phonological pattern in which a normally voiced consonant in final-syllable position is replaced by a voiceless consonant, as in ‘bat’ for ‘bad’.  It has been claimed that term ‘final consonant devoicing’ is inaccurate because the feature in question is tenseness, rather than voice, but this is not considered to be important in an account …

Filopodia

Filopodia (singular filopodium) are action-rich bulbous-shaped protrusions that function like antennae for a cell to probe the surrounding extracellular environment.  They are 60-200 nm in diameter made of parallel bundles of 10-20 actin filaments.  Filopodia are classified as pseudopodia (temporary protrusions and retractions of the cytoplasm of eukaryote cells).  As such, they have a simpler …

Filial imprinting

The process through which early social preferences become restricted to a particular stimulus, or class of stimuli (e.g., the mother or a moving artificial object), as a result of exposure to that stimulus.  First described in detail in 1935 by Konrad Z. Lorenz (1903-1989).  See Critical period, Ethology, Imprinting, Sexual imprinting

Fibroblasts

The most common type of connective tissue cells that are flat and spindle shaped with processes extending out from the ends of the cell body.  They secrete and synthesize an extracellular matrix that is rich in collagen proteins and other macromolecules (large complex molecules, including not only proteins but also carbohydrates, lipids and nucleic acids, …

Fibrillation

A small, localized, irregular and involuntary muscle contraction involving single muscle fibers that is ‘finer’ than that produced by fasciculation.  Most often evident in neural lesions involving motoneurons, peripheral nerves and spinal roots.  Remains until nerve becomes re-innevated or fibrotic (development of excess fibrous connective tissue).  Fibrillation potentials measure derived from EMG have not been …

Fibroblast growth factor (FGF)

A cytokine implicated in cell differentiation and proliferation, and morphogenesis more generally.  To date, twenty distinct fibroblast growth factors have been discovered, numbered consecutively from 1 to 20, each with quite diverse functions.  For example, FGF-2 has been to shown to promote axon branching of cortical neurons through influencing the morphology and behavior of growth …

Fetus

A mammalian embryo from the time it begins to assume the form of the adult until birth (in the human at about the gestational age of 7 weeks).  See Antenatal, Corticobulbar tract (CBT), Embryo, Fetal programming, Gestational age, Infancy/infant, Newborn, Perinatal, Perinatal focal damage, Toddlers

Fetal programming

The process whereby interactions between the genome and the environment, in utero and during infancy, produce structural and functional adaptations that alter susceptibility to common diseases (e.g., diabetes) in adult life.  The fetal programming or fetal origins of adult disease hypothesis started with findings from retrospective epidemiological studies in the 1990s.  It holds that prenatal …