Lecture 34. Sensation and Perception

Question 1

What does sensory input inform an animal about ?

Answer 1

The environment and therefore drives bahvior

Question 2

What is sensory filtering regarded as ?

Answer 2

Critical to recognition of the sign stimulus

Question 3

What does a sign stimulus trigger ?

Answer 3

A fixed action pattern

Question 4

What is the model systems approach ?

Answer 4

1. Simpler nervous system

2. Ecological specialisms

Question 5

What do invertebrates and vertebrates nervous systems share ?

Answer 5

Properties at a molecular and cellular level eg. neurotransmitters

Question 6

What are the morphological differences in a vertebrate and an invertebrate ?

Answer 6

1. Vertebrate - Spinal cord and brain

2. Invertebrate - Segmental nervous system

Question 7

What is an identified neuron ?

Answer 7

A neuron that is recognisable as it occurs in the same location, morphology, chemistry and has the same function in every member of a species

Question 8

What is the connectome ?

Answer 8

A map of the neural connectivity’s to understand brain function

Question 9

How many neurons does the C. elegans have ?

Answer 9

302 neurons

Question 10

How many neurons in the human brain ?

Answer 10

10 ^12

Question 11

How many neurons in the mouse brain ?

Answer 11

70, 000, 00

Question 12

How many neurons in the fly brain ?

Answer 12

100,000

Question 13

What did Wilder Penfield study ?

Answer 13

The sensory and motor homunculus

Question 14

What does the size of cortical representation reflect ?

Answer 14

Sensory input from different parts of the brain

Question 15

What is cortical representation not ?

Answer 15

It is not static but modifiable through changing input and learning

Question 16

What animal did Merzenich experiment on ?

Answer 16

Monkey

Question 17

What did Merzenich experiments show ?

Answer 17

1. Progressive change in cortical representation after transection of the median nerve
2. Synaptic plasticity is thought to underlie cortical plasticity

Question 18

What is sensory cancellation ?

Answer 18

How a self generated sensory input is ignored

Question 19

What is one form of sensory input that is often irrelevant ?

Answer 19

Any input that we are causing by our own actions

Question 20

What is an example of sensory cancellation

Answer 20

1. Why cant humans tickle themselves

Question 21

What is corollary discharge ?

Answer 21

Any excitation pattern that results in a movement that will cause a displacement of the visual image on the retina may have a corollary discharge into the visual centers to compensate for the retinal displacement

Question 22

What does the weakly electric fish generate ?

Answer 22

Electrical signals to probe the environment

Question 23

What can the fish return signal in the brain do ?

Answer 23

The electrolocation commands can be gated, amplified or predicted

Question 24

How do visual cues convey information ?

Answer 24

Rapidly

Question 25

What are visual receptors dependent on ?

Answer 25

Light

Question 26

What are displayed during foraging and social scenarios ?

Answer 26

Specific pigmentation patterns

Question 27

How can animals create visual signals ?

Answer 27

By small subcutaneous photophores in the muscle tissue

Question 28

What type of behavior can sensory input drive ?

Answer 28

Collective behavior

Question 29

What is gregarization ?

Answer 29

Locusts altering behavior from solitary to swarming

Question 30

What are polyphenic animals ?

Answer 30

Animals that can exhibit different characteristics under different circumstances

Question 31

What is correlated with the degree of behavioral gregarization ?

Answer 31

Serotonin in the thoracic CNS