01:830:301 Lecture Notes - Lecture 5: Focal Length, Image Resolution, Refraction
Document Summary
Small gap between pre-synaptic and post-synaptic neurons. Modify likelihood of post-synaptic neuron firing: inhibitory and excitatory effects in post-synaptic neuron. Firing of pre-synaptic neuron either increases chances of post-synaptic neuron firing (excitatory synapse)- + charge (depolarization: decrease chances of post-synaptic neuron firing (inhibitory synapse) =- charge (hyperpolarization) One impulse is not the basic element of information. Continuous information is encoded by rate of firing. Firing rate is always measured relative to baseline. Biological approaches: lesion studies, single-cell recording, eeg, neuroimaging. Record brain activity using electrodes on scalp. Difficulties: hard to pin point precisely, many signals too weak. Highly active regions will have greater blood flow. Light as particles: travels in straight lines (rays) but waves are not obstructed, light is obstructed, smallest packet: photon. Refraction: bends when it encounters a new medium. Def 1: a structure/ organ sensitive to light: ex. Epidermis of earthworm: problem: cannot detect a pattern spatial vision .
