W7

Question 1

Prinzip der spezifischen Energie (labled line)

Answer 1

Stimulation of a type of receptor always produces the correct sensation

Question 2

Kodierungsprinzip

Answer 2

analogue (amplitude) signal is transformed into digital (frequency) signal

Question 3

Prinzip der Topography

Answer 3

Neigouring receptors connect to neighbouring cells in brain.

Question 4

Prinzip der lateralen Inhibition

Answer 4

Lateral inhibition is often used to increase sensitivity and contrast.

Question 5

Prinzip der parallelen Verarbeitung

Answer 5

Sensory modalities are often divided into submodalities. e.g. deconstruction of the visual impression

Question 6

Relayprinzip

Answer 6

Information is sent through the Thalamus (except olfactory)

Question 7

Prinzip der “gain control”

Answer 7

The more intensive the stimulation, the bigger the perceivable difference.

Question 8

Pathway of olfactory signal…

Answer 8

Olfactory receptors - Olfactory bulb - olfactory targets: pyriform cortex; olfactory tubercle; amygdala;entorhinal cortex - Orbitofrontal cortes; thalamus; hypothalamus; hippocampal formation

Question 9

Receptors for taste…

Answer 9

A. Salt - Na+ ionotrope
B. Acid - H+ ionotrope
C. Sweet - G-protein (metabotrope)
D. Amino acids (umami) - G-protein
E. Bitter - Gustductin (metaotrope)

Question 10

Slow - touching and static pressure

Answer 10

Merkel cells (close to epidermis)

Question 11

slow - stretching of skin

Answer 11

Ruffini corpuscles (kolben)

Question 12

fast - touching and dynamic pressure

Answer 12

Meissner corpuscle (Zellkomplexe)

Question 13

fast - deep pressure, vibration

Answer 13

Vater - Pacini corpuscles (Körperchen)

Question 14

slow/high- pain, temperature

Answer 14

free nerve-endings

Question 15

What are they two pathways of the somatosensory system?

Answer 15

1. dorsal column-medial lemniscus pathway (lower and upper body pathways undergo a switch of position in the medulla from lateral to contralateral side of the brain, and also in the thalamus (medial/distal) - e.g. Lower body starts medially on the right and ends medially of the left
2. Trigeminal system (face) (is contralateral)

Question 16

Olfactory receptors

Answer 16

• G-protein
• excitatory through CA2+/Na+ and Ca2+gated CL- channels (Cl- in excitatory because of the high cl- concentration inside the receptor cells.

Question 17

Cells in olfactory bulb.

Answer 17

• glomerulus
• periglomerular (easily replaced)
• tufted
• Mitral (different scents activate these cells. The combination of mitral cells activated determines the nature of the scent.

Question 18

Slow and fast adapting receptors

Answer 18

slowly adapting - tonisch

rapidly adapting - phasisch