threshold
"Threshold is like a gate - if threshold is high it is more difficult to get past it"
"The threshold is like how much sensory input is needed to excite a neuron. For example, like you said, if the neuron's threshold is 10, it will only get exited at ten. Not 7, not 9, not 9.5, ONLY 10. What actually happens is, if there is enough excitement to the neuron, the action potential (which is basically just a rush of ions) gets transmitted, and the neuron is 'excited'. But, if there isn't enough stimulation, the rush of ions doesn't happen, and so the neuron doesn't get excited."
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.