INDEX 



775 



Protoplasm 



differential irritability, 369 

 Pulvinar 



sensory sy terns, correlation and, 31 1 

 Pupil 



astigmatism and, 652 



axis 



definition, 653 



cephalopods, 637 



chief ray and, 652 



entrance and exit, 652 



image formation and, 652 

 Pupillography 



stray light in, 667 

 Pure tone threshold : see Audition 

 Purkinje images 



see also Vision 



importance of, 656 

 Purkinje phenomenon 



see also Vision 



description, 682 

 Pyramidal neurons 



collateral activity of fibers, 306 



postsynaptic impulse in, 303 



Receptor cells 



electrical responses, 165 



functional components, 165 



generator potential and, 127 



in higher invertebrates, 37 1 



in insects, 373 



in invertebrates, 375 



lines of research, 365 



reaction to stimuli, 366 

 Receptor potential, 130-135 



absolute magnitude, 134 



definition, 130, 393 



depression of, 1 35 



duration of stimulus, 134 



from different receptors, 131 



impulse initiation and, 132 



latency and, 1 29 



nerve terminals, 1 30 



phasic behavior, 131 



procaine and, 136 



size of the exciting displacement, 133 



sodium lack and, 1 36 



source of energy, 143 



stimulus and, 1 32 



summation and, 134 



threshold 



depression and, 135 



tonic behavior, 131 



velocity of the displacement and, 133 

 Receptors, 123-144 



see also various types of receptors 



adaptation of, 124, 125, 144 



central control of, 741-759 



definition, 123 



discharge frequency of, 126-128 



electronmicroscopy of, 141 



excitation of, 123, 129, 130 



excitation reduction and, 126 



initiation of impulse, 142 



invertebrate 



nonphotic, 369-383 

 photic, 621-642 



junctional, 209 



minute structure of, 141, 142 



potentials of, 130-135 



repetitive firing, 127 



role, 123 



sensitivity and time factors, 124 



sodium lack and, 136, 137 



specific sensitivity, 1 24 



time course, 129 



tonic, 126 



transmitter action on, 139-141 

 Recruitment 



repetitive stimulation and, 31 i 

 Reflexes 



see also individual reflexes 



synaptic determinants of, 147-194 

 Refraction, 654-656 



coincidence optometer, 659 



indices of 



measurements, 656 



retinoscope and, 659 

 Refractory period 



barbiturates and, 308 



ionic hypothesis and, 64 



visual cortex, 308 

 Repetitise firing : see Nerve fibers 



current theories, 117 



definition, 83 



equilibrium potential and, 162 



external K concentration and, 1 1 7 



potassium potential and, 168 

 Reticular activating system; see Reticular 



formation 

 Reticular formation 



activation, 42 1 



anoxic convulsions, 339 



ascending sensory paths and, 752 



as functional unit, 42 1 



as origin of generalized convulsions, 



335 

 ascending sensory paths and, 752 

 attention and, 367 

 auditory pathway and, 591 

 behavior and, 755 

 bulbar relays and, 745 

 cerebral afferent systems and, 747-749 

 control of afferent paths by, 745-747 

 dorsal column relays and, 745 

 efferent effects upon retinal activity, 



745 

 efferent pathways and, 757 

 hearing and, 591 

 inhibition of spinal relays, 746 

 medial lemniscal system and, 42 1 

 pain perception and, 756 

 rapid phase of nystagmus and, 559 

 role in tonic and clonic spasms, 340 



sensory system, correlation and, 3 1 1 



spinal ascending relays and, 745 



spinal motor activity and, 561 



spinothalamic tract and, 421 



stretch receptors and, 743 



vestibular stimulation and, 561 

 Retina, 665-669, 671-710 



see also Cones; Rods; Electroretin- 

 ography; Ocelli 



action potentials from, 617 



conduction across surface, 696 



conjugate focus, 658 



damage and ERG, 700 



efferent control of, 745 



electrical activity of, 696-704, 710 



entoptic phenomena, 669 



histology of, 693-696 



illuminance of, 665, 669 



inhibition in, 706 



neural activity in, 693-710 



on-system and off-system in, 705 



receptive fields and adaptation, 705 



spike discharge, 704 



stimulation 



cortical localization and, 726 



type and ERG, 698 



vitamin A and, 68g 

 Retinal image, 647-691 



see also Image formation 



blur, 667 



size, definition, 654 

 Retinene 



see also Visual pigments 



rhodopsin and, 674 

 Retinitis pigmentosa 



vitamin A and, 691 

 Rhinencephalon 



EEG and electrical stimulation of, 351 



epilepsy, partial and, 350 



olfactory cortex and, 546 

 Rhodopsin, 672-676 



see also Visual pigments 



adaptation and, 686 



anagenesis, 673 



as visual pigment, 672 



bleaching and resynthesis, 686 



changes during vision, 672 



neogenesis, 673 



retinene and, 674 



scoptic sensitivity and, 682 



synthetic system, 674 



vitamin A and, 672, 674 

 Righting reflex 



mechanism of, 560 

 Rods 



see also Retina 



electroretinogi'am and, 699 



flicker fusion and, 708 



histology of, 693 



modulators in, 708 



sensitivity of, 699 



visual pigments in, 671 



