trivia Flashcards
sensory neurons
none
motor neurons
none
interneurons
These are by far the most numerous (in the
human brain)
glial cells
long thought to have a purely
supporting function to the neurons
cerebral cortex
cortical tissue is the most highly
developed area of the brain in humans - four times bigger
than in gorillas
lateralization of the brain
Many of the cortex’s functions are carried out by
both sides of the brain, but some are largely lateralised to
one cerebral hemisphere or the other. Areas concerned with
some of these higher functions, such as speech (which is
lateralised in the left hemisphere in most people), have been
identified.
On the receiving side of the cell, the dendrites have close
contacts with incoming axons of other cells, each of which is
separated by a miniscule gap of __. These junctional spots are
named __, from __ words that mean “__”.
On the receiving side of the cell, the dendrites have close
contacts with incoming axons of other cells, each of which is
separated by a miniscule gap of about 20 billionths of metre. These junctional spots are
named synapses, from classical Greek words that mean “to
clasp together”.
Cajal
Ramon Y Cajal, father of modern neuroscience. photograph shows him in 1890.
Hodjkin
Alan Hodgkin and Andrew Huxley won the Nobel Prize for discovering the mechanism of transmission of the nerve impulse. They used the "giant axon" of the squid in studies at the Plymouth Marine Biology Laboratory
Huxley
Alan Hodgkin and Andrew Huxley won the Nobel Prize for discovering the mechanism of transmission of the nerve impulse. They used the "giant axon" of the squid in studies at the Plymouth Marine Biology Laboratory
action potential speed
in myelinated neurons,
action-potentials can race along at 100 metres per second!
action potential frequency
The most efficient axons can
conduct action potentials at frequencies up to 1000 times
per second.
synaptic cleft
20 nanometer gap that the chemical messenger diffuses across
excitatory and inhibitory neurotransmitters
The main excitatory neurotransmitter in the brain is
glutamate. There are
two inhibitory neurotransmitters – GABA and glycine.
synaptic transmission time
Synaptic transmission is a very rapid process: the time
taken from the arrival of an action potential at a synapse to
the generation of an epsp in the next neuron is very rapid -
1/1000 of a second.
alcohol dependency
about one in ten of regular drinkers will become dependent
alcoholics
alcohol deaths
More than 30,000
people die every year in Britain from alcohol-related diseases.
pregnancy and alcohol
Pregnant mothers who drink run the risk of having
babies with damaged brains and low IQ’s.
smoking deaths
More than
100,000 people die every year in Britain from smoking-related
diseases.
cannabis dependency
About one in ten users may become
dependent
cannabis and mental illness
Although not yet proven,
there is some evidence that heavy use by young people might
trigger the mental illness schizophrenia in
susceptible individuals.
“mid-week blues”
Animal experiments have shown that Ecstasy can
cause a prolonged, perhaps permanent reduction of
serotonin cells. This might account for the “mid-week blues”
suffered by weekend ecstasy users. Every year, dozens of
young people die after taking it
amphetamines and mental illness
Frightening schizophrenialike
psychosis can happen after Dexedrine and Speed.
amphetamines
man-made chemicals that include
“Dexedrine”, “Speed”, and the methamphetamine derivative
called “Ecstasy”. also d-LSD