agent A role (the performer of an action) in argument
structure (JOHN cooked dinner).
allele Alternative versions of a gene. Perhaps
20 percent of your expressed genes have a different allele on the other
chromosome; that is, you are heterozygous for that gene and might
switch to using it under some conditions. One reason that hybrids don’t
breed true to type is that parents are often passing on their less-used
allele. Inbred strains have less heterozygosity.
altruism Doing something for another’s benefit, at
expense to yourself – but not necessarily at the expense of your genes, as
when you aid relatives. In reciprocal altruism (RA), sharing with nonrelatives
is eventually reciprocated, though the system is weakened by freeloaders
("cheaters").
area When capitalized, it’s a Brodmann
Area, a subdivision of cerebral cortex based on the relative thickness of
the six layers. Area 17 is better known as primary visual cortex; it seems to
be a functional unit, but Area 19 comprises at least six major functional
units. A territory or work space is a generic lower-case area, occupied
temporarily by active patterns of cloned hexagons.
argument structure The assignment of thematic
roles to the constituents (noun-phrases, prepositional phrases, even
clauses) that represent the participants in actions, states, and events
creates arguments. Some of these arguments are obligatory, depending on
the meaning of the verb. Argument structure is what determines whether a verb
will have one, two or three obligatory arguments. Thus, "sleep" will
have only one, a sleeper. "Break" will have two, a breaker and
something broken. "Give" will have three, a giver, a gift, and a
receiver. Unlike phrase structure, argument structure does not assign
either linear ordering or hierarchical relationships to its components;
argument structure has to be mapped onto phrase structure in order to provide
these.
axon The neuron’s tail-like "wire," a
long (0.1 - 2,000 mm), spider thread thin portion of the neuron that carries
voltages between the neuron’s input sites (concentrated on cell body and
dendritic tree) and the neuron’s outputs, its many-branched axon terminals
that make synapses onto downstream neurons. It’s typically a one-way street,
messages flowing from the dendrites and cell body to the far end of the axon
where synapses are made.
bee dance The honeybee appears, at least in the
context of a simple coordinate system, to have broken out of the usual animal
communication that has a single meaning. When the bee returns to her hive, she
performs a " waggle dance" in a figure_8 that communicates
information about the location of a food source that she has just visited. The
angle of the double racetrack’s common axis communicates the direction of
the new-found food, and the number of circuits that she does around the loops
communicates the distance from the hive. But, as Bickerton said in Language
and Species,
All other creatures can communicate only about things that
have evolutionary significance for them, but human beings can communicate
about anything.... Animal calls and signs are structurally holistic
[and] cannot be broken down into component parts, as language can.... Though
in themselves the sounds of [human] language are meaningless, they can be
recombined in different ways to yield thousands of words, each distinct in
meaning.... In just the same way, a finite stock of words... can be combined
to produce an infinite number of sentences. Nothing remotely like this is
found in animal communication.
beneficiary A role (doing something for someone)
in argument structure (I bought it FOR YOU).
binding Binding theory describes the conditions that
identify constituents without independent reference – pronouns and anaphors
(reflexives, reciprocals, and the like). See the appendix.
bonobo Pan paniscus,
formerly called the " pygmy chimpanzee," and the last great ape
species to be identified. Until 1927, they were confused with the chimpanzee, Pan
troglodytes – with the old common name arising because they were said to
be the "chimpanzee of the pygmies," living as they do on the left
bank of the Congo River in equatorial forests (they’re called the "Left
Bank Chimps" for other reasons, too). While of a more slender body build
than chimps, bonobos are not particularly smaller. Humans last shared a common
ancestor with both Pan species about 5 million years ago. The two Pan
species diverged at about the beginning of the ice ages, 2.5 million years
ago, roughly the same time that the Australopithecus lineage spun off
the Homo lineage.
bottleneck In population biology, an occasion when
genetic variability in a population was greatly simplified by the loss of
alternative alleles – not because of selection against them but
simply due to dropouts that occur by chance, because of reduced choice in
mates. This happens when population numbers are greatly reduced for a time;
the re-expansion then populates the world from the smaller range of variation.
central nervous system (CNS) The brain, spinal cord,
and the retina (all the rest is the peripheral nervous system).
cerebral cortex The outer 2 mm (that’s two thin
coins worth) of the brain’s cerebral hemispheres with a layered structure.
It isn’t required for performing a lot of simple actions but seems essential
for creating new episodic memories, the fancier associations, and many new
movement programs. Paleocortex, and archicortex such as hippocampus, has a
simpler structure and earlier evolutionary appearance than the
six-plus-layered neocortex.
cheater detection A feature of reciprocal altruism
theories, what you use to identify freeloaders who receive but rarely give
back.
chunking Collapsing multiple-word phrases into a
single word, in the manner of acronyms.
clause A verb and all its associated arguments. See phrase.
code In cryptography, a code is a disguising
transformation that (unlike a cipher) also chunks – and thereby
shortens – the message, as when a number stands for a standard five-word
phrase. More generally, as in genetic code, code refers to the
transformation of a representation’s short form into its long-form
implementation. As such, it is analogous to a matrix. Code may also
simply refer to the short form itself, such as a DNA base-pair sequence
capable of generating a particular protein.
columns A minicolumn is a cylindrical group of about
100 neurons about 0.023 mm in diameter, extending through all the layers of neocortex
and usually organized around a dendritic bundle; the orientation column is an
example. Macrocolumns are a hundred times larger in area (and about 0.4 -1.0
mm across) and often more like curtain folds than cylinders; they are
typically identified by common inputs, e.g., the ocular dominance columns of
visual cortex.
corticocortical connection An axon or axon
bundle connecting one patch of cerebral cortex to another. Some remain local,
within the superficial layers of cortex, while others go tunneling through the
white matter to distant targets – some, via the corpus callosum, to the
other cerebral hemisphere.
creole Children invent a new language – a creole
– out of the words of the pidgin protolanguage they hear their
immigrant parents speaking. A pidgin is what traders, tourists, and
"guest workers" (and, in the old days, slaves) use to communicate
when they don’t share a real language; pidgin sentences are unstructured and
short, while those in creoles have the features of universal grammar.
Darwin Machine The Calvin 1987 coinage, on the Turing
Machine analogy, for any full-fledged Darwinian process incorporating the six
essentials for the Darwinian algorithm. Species evolution, the immune
response, some genetic algorithms, and the hexagonal work space competitions
are all examples. Not to be confused with particular models, also named after
Darwin.
dendrite Neurons have branches. At least in neocortex,
dendrites are the receiving branches of the neuron and the axon is the sending
branch. Elsewhere, some dendrites can also act like axon terminals, releasing neurotransmitter
in response to impulses and local voltage changes. There is always a single
thin axon that initiates and propagates impulses to distant
destinations, and there are somewhat thicker dendritic branches that receive synapses
from other neurons’s axon terminals. Pyramidal neurons have a tall tree-like
apical dendrite plus some rootlike basal dendrites.
epigenetic rules Some aspects of development are both
innate and specified by the environment; "epigenetic" applies to the
environmental bits. For example, a plant has two growth states, a positively
phototaxic mode that directs most growth toward the light, and a negatively
phototaxic mode. Some vines initially grow away from the light; then, when
there is enough root structure, further growth is up towards the light; the
vine climbs any tree trunk and its branches. Then some vine tips turn
negatively phototaxic, dropping a branch down to earth – which, upon
reaching soil, digs in to create another set of roots. The behavioral switch
may be provided by genes, but the overall form of the resulting plant
also depends upon what was encountered in the environment along the way. Syntax
too is likely to have epigenetic aspects; the sign-language-deprived deaf
infants might be like plants with only oblique light.
exaptation This was a term intended to cover cases
where an organ with one original function got adapted to perform another
function (such as the swim-bladders becoming lungs when the first marine
creatures became terrestrial). Previously, the term "pre-adaptation"
had been used, but this form is objectionable insofar if it suggests some
degree of prescience. (WHC: I use it anyway.)
gene A unit of heredity, essentially that segment of
a DNA molecule comprising the code for a particular peptide or protein. We
also talk loosely of "a gene for blue eyes" and so forth (
reification strikes again), but many a DNA gene is pleiotropic: it has
multiple (and sometimes very different) effects on its body; like that maxim
about intervening in complex systems, "You can’t do just one
thing."
genotype The full set of genes carried by an
individual, whether expressed or silent alleles. Similar to genome.
Compare to phenotype. What makes living matter so different from other
self-organizing systems is that a cell has an information center, the genes,
concerned with orchestrating the many different processes going on within the
cell, and in such a manner that copies of the cell tend to survive.
goal A role (whoever the action was directed
toward) in argument structure (I gave it TO MARY).
grammar Not to be confused with socially correct
usage. In order to handle novel sentences, we not only need to access the
words stored in our brains but also the patterns of sentences possible in a
particular language. These patterns describe not just patterns of words but
also patterns of patterns. There are three aspects of grammar: morphology
(word forms and endings), syntax (from the Greek "to arrange
together" – the ordering of words into clauses and sentences), and
phonology (speech sounds and their arrangements). A complete collection of
rules is called the mental grammar of the language, or grammar for short.
grammar, universal Each of
the languages of the world has a corresponding mental grammar, constructed as
we learn the language. Though they differ in many ways, the human brain seems
to have a highly specific menu of possibilities for grammatical organization,
known as Universal Grammar, or UG, that structures language learning even when
the input itself is lacking in structure ( pidgins, home sign, and so on).
grammatical morphemes The words (a few dozen in
English) that refer to relations between content words. They are unlike
content words, which refer to concepts of things in the world. They include
words that express relative location (above, below, in, on, at, by, next to),
relative direction (to, from, through, left, right, up, down), relative
time (before, after, while, and the various indicators of tense), and
relative number (many, few, some, the _s of plurality). The
articles express a presumed familiarity or unfamiliarity (the for
things the speaker thinks the hearer will recognize, a or an for
things the speaker thinks the hearer won't recognize) in a manner somewhat
like pronouns. Others express relative possibility (can, may, might),
relative contingency (unless, although, until, because), possession (of,
the possessive version of _s, have), agency (by), purpose (for),
necessity (must, have to), obligation (should, ought to),
existence (be), nonexistence (no, none, not, un_), and so forth.
These are called " closed-class words" because our ways of
expressing relationships are so resistant to augmentation, whereas you can
always create new nouns or verbs.
head See phrase.
impulse Action potential and spike are
synonyms; an impulse is the regenerative change in the voltage across the
neuron’s membrane used for long-distance (more than a millimeter) signaling
in the nervous system. It is brief (1/1000 sec, quicker than any other signal
in the brain but a million times slower than computers) and large (only 1/10
volt but bigger than any other voltage in the brain). Its threshold property
can also be used as a simple decision making mechanism. See also axon,
myelin.
inflections The inflectional system of English alters
a noun when it refers to a multiplicity ("The boy ate three
cookie." Is that correct English?) and alters a verb when it refers
to past time ("Yesterday the girl pet a dog." OK?). Late
learners of English may fail to realize that anything is "wrong"
with these incorrect sentences, as such long-range dependencies are redundant
information that helps out in noisy environments when some words are
imperfectly heard and must be guessed.
innateness "Hardwired by genes" is the
general idea, but it is, more generally, a bit of behavior that arises without
learning. When the individual finds itself in a particular setting, out pops
some complicated behavior. Mating behaviors are innate; some things are too
important to be left to learning. But there isn’t a dichotomy between
innateness and environmental causation; as epigenetic rules show,
something innate may have, via environmental triggers, profound effects on
future form and function.
instrument A role (doing it with something) in
argument structure (Bill cut it WITH A KNIFE).
irregular An irregular noun does not follow the usual
plural rule. By the age of two or three, children learn to add -s.
Before that, they treat all nouns as irregular. But even if they had been
saying "mice," once they learn the plural rule they may begin saying
"mouses" instead. Eventually they learn to treat the irregular nouns
as special cases, exceptions to the usual rule. Verbs too can be irregular:
the past tense of "fly" is "flew" – unless, of course,
the word is being used in some novel manner, as in "The batter flied
out," where the regular -ed form is nonetheless used. Young
children, however, often use the regular form for the central meaning of
"fly," as in "The bird flied away."
inheritance principle Darwin’s great but often
misunderstood insight, that variation is not truly random. Rather than
variations being done from some ideal or average type, small undirected
variations are preferentially done from the more successful individuals of the
current generation, exploring the solution space nearby (not jumping randomly
to somewhere truly unrelated) in the next generation. []
island biogeography The peculiarities of animal and
plant species when largely isolated, with just occasional interbreeding. An
"island" can also be a deep ocean basin, a high mountain valley, or
a patch in a patchy resource distribution that prevents migration. Islands
often have a reduced number of species, so traditional predators or parasites
may be lacking. Species often arrive in small numbers, so bottlenecks are a
standard feature of island populations.
language acquisition device The LAD is a hypothetical
mechanism in the human brain that enables any normal human to learn any of the
5000+ human languages (or any possible human language). Its existence has
never been empirically demonstrated and, within the present approach, it would
seem to be unnecessary to assume any LAD as a distinct, self-encapsulated
unit.
meme Richard Dawkins’s 1976 coinage, on the analogy
to gene (with a little aid from mime and mimic), for a cultural copying
unit, such as the word or melody that is mimicked by others.
memory, dual trace Hebb’s
1949 coinage for separate systems implementing short- and long-term memories:
active (spatiotemporal) and passive (spatial-only) memory traces.
memory, episodic One-trial
learning involving distinct episodes, such as being an eyewitness to an
accident. Such memories are notoriously malleable, influenced by subsequent
events and the mistakes made in earlier recall attempts.
movement Where a word moves out of its usual place in
a sentence, as in the wh- words. See the appendix.
myelin The fatty, porcelain-colored insulation around
an axon that reduces its energy consumption while also making the
impulse travel much faster. It is wrapped in layers, like a bandage.
neocortex All of cerebral cortex except for
such things as hippocampus, the simpler layered structure that lacks the
patterned recurrent excitatory connections and columnar structures that make
the six-layered neocortex so interesting.
nervous system The whole works, both central
nervous system (CNS: brain, spinal cord, and retinas) and peripheral
nervous system (most sensory and muscle connections, plus the clusters of
neurons called ganglia).
neuron The nerve cell, whether sensory neuron,
interneuron, or motor neuron. There are about 1012 neurons in the
human brain and spinal cord; the neocortex alone is said to have 1011.
The cell body of the neuron is the widest section, thanks to containing
the cell nucleus, and there are many processes branching off, receiving inputs
and distributing outputs. See dendrite, axon.
neurotransmitter A molecule such as glutamate or
acetylcholine that is released from an axon terminal (often by the arrival of
an impulse), diffuses across a narrow extracellular space, and binds
with a receptor on the surface of the postsynaptic cell. (These three
parts are collectively called the synapse). Many dozens of
neurotransmitters have been identified over the years, and a given axon
terminal may release more than one kind.
niche The "outward projection of the needs of an
organism" such as food resources, migration routes, camouflage from
predators, suitable housing and sites for effective reproduction. An empty
niche is a proven niche space that is temporarily unoccupied by a tenant
species.
parcellation Fragmentation; breaking apart a
population into smaller, isolated units ("parcels" or
"patches"), as when rising sea level converts a hilly island into an
archipelago of former hilltops. See also island biogeography.
patient A role (who- or whatever undergoes the
action) in argument structure (John cooked DINNER). Often
described as theme.
phenotype Usually "body" but actually the
entire constitution of an individual (anatomical, physiological, behavioral)
resulting from the interaction of the genes with the environment. As Dawkins
emphasized in The Extended Phenotype, can even include such things such
as bird nests.
phoneme The units of vocalization distinguished by
native speakers of a language. Unlike ape calls and cries, phonemes are all
meaningless by themselves, having meaning only in combinations ( words). It is
important to realize that phonemes are categories that standardize. For
example, Japanese has a phoneme that is in between the English /L/ and /R/ in
sound space. Those English phonemes are mistakenly treated by Japanese
speakers as mere variants on the Japanese phoneme. Because of this "
capture" by the familiar category, those Japanese speakers who can't hear
the difference will also pronounce them the same, as in the familiar rice-lice
confusion.
phrase A group of words consisting of a head (which
can be a noun, verb, preposition, etc.) and its modifiers. Clauses
consist of groups of phrases. Each phrase is labeled according to its
head. If the head is a noun, the phrase will be a noun phrase
("the tall blond man," where "man" is the head). If the
head is a preposition, the phrase will be a prepositional phrase
("with one black shoe," where the head is "with").
phrase structure The results of the procedure by
which words and phrases are assembled to form clauses and sentences. Formerly
an independent module in generative grammar, its features now fall out from
the principles that govern other modules. However, phrase structure trees are
still drawn by syntacticians to show the relationships between words, phrases,
and clauses. Such trees are hierarchically structured and, nowadays, usually
binary-branching.
pidgin A contact medium liable to spring up wherever
speakers of several different languages have to communicate without any
language in common. In its early stages of development a pidgin is a form of protolanguage:
that is to say, it lacks any kind of formal structure. Pidgin utterances
consist of small groups of content words strung together in a purely ad hoc
fashion. A pidgin, if it endures long enough, may stabilize, expand and, after
several generations, approach the status of a full natural language. If a
pidgin, regardless of its stage of development, is acquired by children, they
convert it into a creole.
postsynaptic The postsynaptic neuron’s dendrite
receives neurotransmitter, rather in the manner of sniffing perfume, and
changes the permeability of its membrane to certain ions, usually Na+,
K+, Cl-, or Ca++ in some combination. Ions
flowing through the membrane in turn produce the voltage change known as the postsynaptic
potential (PSP). If excitatory, it is called the EPSP; if inhibitory, the
IPSP.
protolanguage Any form of communication that contains
arbitrary, meaningful symbols but lacks any kind of syntactic structure. Forms
of protolanguage include the communication of
"linguistically"-trained apes and other animals, pidgins in
their early stages, the speech of nonproficient second-language learners, and
that of children under two.
pyramidal neurons The excitatory neurons of
neocortex. They typically have a tall apical dendrite (an exception is
the spiny stellate neuron) and a triangular-shaped cell body (from whence the
name), from which their axon leaves. The neurons contributing to the
pyramidal tract (alias the corticospinal tract, named for the triangular shape
of the axon bundle as it traverses the medulla) are themselves pyramidal
neurons, but most pyramidal neurons send axons elsewhere.
receptive field A map of the inputs to a single neuron,
e.g., those parts of the skin of the hand that produce excitation or
inhibition of a cortical neuron (antagonistic surrounds are especially
common). The limited view of the world as seen by a single neuron. []
recombination There are several connotations: (1) The
shuffling of genetic material between an individual’s two chromosome pairs
that occurs just prior to the production of ova or sperm (the crossing-over
phase of meiosis); and (2) the production of a new individual through the
union of a sperm and an ovum from two parents at fertilization.
schema As in "schematic outline," it’s a
mental item more abstract than a rich mental image of an object. In some
cognitive contexts, it is used more narrowly for those things like more,
less, bigger, inside – things grounded in our everyday experiences,
often making reference to our own body moving through our daily world.
Movements need something similar, and schema is often used to refer to
standard movement programs.
semantics The "meaning" of words, those
connotations that you might look up in a dictionary (as opposed to syntax).
source A role (taking it from someone or
something) in argument structure (I bought it FROM FRED).
synapse The synapse is the junction between neurons
across which communications flow, usually in the form of neurotransmitter molecules
secreted by the presynaptic axon terminal that diffuse a short distance
across the extracellular space (the synaptic cleft) to the postsynaptic
neuron, on whose membrane are some receptor molecules to which the
neurotransmitter molecules reversibly bind. While they are bound, they open up
an ion channel through the postsynaptic membrane, producing postsynaptic
current flow. Most drugs affecting the CNS operate by interfering with
synaptic transmission. See also dendrite, neuromodulator,
neurotransmitter, postsynaptic.
syntax The set of rules and
principles that determine how sentences are formed, and the structures
resulting from sentence formation.
theme A role (who- or whatever undergoes the
action) in argument structure (John cooked DINNER).
UG See grammar, universal.
word order A simple convention that aids in
identifying roles, such as the subject-verb-object order (SVO) of most
declarative sentences in English ("The dog bit the boy") or the SOV
of Japanese. At least in English, the who-what-where-when-why-how questions
deviate from basic word order: "What did John give to Betty?" is the
usual convention (except on quiz shows in which questions mimic the basic word
order and use emphasis instead: "John gave what to
Betty?"). Some languages such as Latin lack a systematic word order,
instead using characteristic inflections or even separate words (as when
English uses "he" for a subject and "him" for an object,
although both have singular, masculine, third-person referents) to help
disambiguate the sentence.