Ch. 2 Flashcards
What are levels of analysis?
The idea that a topic can be studied in a number of different ways.
What is a nerve net?
A network of nerves seen by 19th century anatomists who stained slides of brain tissue.
Why was a nerve net observed and not individual neurons?
Because technology at the time was not good enough to zoom any further.
What is the neuron doctrine?
The idea that individual cells transmit signals in the nervous system and that they are not interconnected.
Who introduced the concept of individual neurons that communicate with others to form circuits?
Ramon y Cajal.
What are used to record electrical signals from neurons?
Micro-electrodes.
How long does an action potential last?
Around 1 millisecond.
How does a nerve impulse change as the intensity of a stimulus increases?
The frequency of the action potentials increases, the action potentials themselves stay the same though.
What is the principle of neural representation?
Everything a person experiences is based on representations in a person’s nervous system.
What are feature detectors?
Neurons that respond to specific stimulus features such as orientation, movement, and length.
What did the discovery of feature detectors lead to?
The idea that the thousands of neurons that fire when we see something are firing to different features of the thing.
What has research on monkeys revealed about feature detectors?
There are neurons that fire to something as specific as a hand with fingers pointed upwards.
What is hierarchical processing?
The progression of neural firing from lower to higher areas of the brain. i.e., from the visual cortex up to the temporal lobe.
What does sensory code refer to?
How neurons represent various characteristics of an environment.
How does the firing of neurons relate to memory and actual perception?
Neural patterns for recalling something differ from neural patterns when actually perceiving that memory.
