Lecture Conditioned reflexes Inhibition of conditioned reflexes Vinnitsia

Lecture: “Conditioned reflexes. Inhibition of conditioned reflexes. ” Vinnitsia - 2013

Reflexes: unconditioned (Sechenov) and conditioned (Pavlov) Conditioned reflexes are individual, temporary reactions, acquired by the organism as a result of individual development on the basis of unconditioned reflexes with participation of the higher nervous centres. Ex. Lamp- conditioned stimulus Food – unconditioned (reinforcement) Saliva secretion– response reaction n

Difference between the conditioned and unconditioned reflexes Unconditioned 1. Inborn, inherited reactions 2. Species-specific 3. Stable 4. Has definite receptive field 5. Can be without brain. cort. 6. Most of them for all life n Conditioned 1. Acquired as a result of “life experience” 2. Individual 3. Unstable 4. Different receptive field 5. Need brain cortex 6. Temporary, can disappear (extinguish) 7. Are built on the basis of unconditioned reflex n

Classification of the conditioned reflexes 1. According to Biological importance n 2. According to the effect n 3. According to the receptor field localization n 4. According to the kind of receptors, under the action of the conditioned stimulus n 5. According to feelings n 6. Natural and laboratory (artificial) n 7. Conditioned reflexes to time n

8. Conditioned reflexes of the second and the third orders n 9. Chain-like conditioned reflexes n 10. Instrumental conditioned reflexes n Instincts Motivation

Rules for building of the conditioned reflexes 1. Combination of conditioned and unconditioned stimulus 2. Conditioned stimulus should be given 1 -5 sec before 3. Unconditioned stimulus should be stronger 4. Conditioned stimulus should be indifferent 5. Isolated room to prevent outside stimuli 6. The animal should be healthy and active 7. To exclude the stimuli from visceral organs 8. The experiment should take place at the same time every day

9. Several dozens of combinations should be done during the experiment 10. At the end of the experiment reinforcment should be given 11. To know if conditioned reflex has been formed The law of the strength (Pavlov) There is a direct dependence of the intensity of The conditioned reflex on the strength of the conditioned stimulus limitation: transmarginal inhibition

Dynamic stereotype Biological importance of conditioned reflexes Structure and mechanism of the temporary connection formation C 1 - C 2 (cortex) S 1 - S 2 (subcortex) C 1 -S 2 -C 2, S 3 -S 4, S 5 -S 6

Conditioned reflex is a kind of memory n Long-term memory

Inhibition of conditioned reflexes: Unconditioned (external): n External (distraction n of attention) Transmarginal (protective) Phases states: 1. Paradoxal 2. Ultraparadoxal 3. Equalizing 4. Inhibitory n Conditioned (internal): n Extinction n Differentiation n Delayed n Conditioned inhibitor n

Extinction – if conditioned stimulus is not reinforced by unconditioned for many times (forgetting) Differentiation: 900 Hz(-), 1000 Hz(+) if one of them is not reinforced Conditioned inhibitor: lamp(+); lamp, sound(-) Complex without reinforcment becomes inhibitor n Delay: if reinforcment is later (2 min), response (saliva) also will be later for 2 min (patience, self-control)