Chapter 3: Habituation/Sensitization

Non-Associated Learning

Learning that does not require specific association with actions or consequences

Habituation

a decrease in responding to a repeated stimuli

• “getting used to something”

What is the simples form of learning?

Habituation

What are key factors of Habituation:

• Must occur over time

• Long-Lasting effects

• Specific stimuli & Specific Response

Sensitization

An increase in awareness to an arousing/ emotional stimuli

Key Factors in Sensitization:

• Occurs quickly

• Not long-lasting

• Generalized stimulus

What are the 3 main parts of a Simple Reflex:

1. Sensory receptor detects stimulus and fires AP

2. Interneuron relays signal to motor neuron

3. Motor neuron drives a muscle contraction

Sensory Adaptation

Lack of response to a prolonged stimulus in the environment

• Not Learning

Main difference between Sensory Adaptation and Habituation

• Sensory adaptation occurs when the sensory neuron stops relaying signal, where as Habituation occurs when the interneuron stops relaying signals

  • Only Habituation is Learning

Dishabituation

When a new stimulus generates the same response as the old habituated response

• “Un-learning”

Comparative Psychology

Study of behavior and mental processes of non-human animals

Reasons for Comparative Psychology:

• Some experiments would be unethical to humans

• animals have simpler neural systems

• Reduces participants characteristics or bias

Reasons against Comparative Psychology:

• Humans are not the same as animals

• Human brain structures differ from animals (more developed forebrain)

• we can only observe behavioral responses in animals

Preferential Viewing Test

Test that says whether a baby can recognize a stimulus

Explain a babies behavior in a Preferential Viewing Test:

The baby spends more time looking at a new stimulus, however, the baby is habituated, looking at the object for less time the more times he is shown that object

What happened in Johnston Hamster's smelling experiment?

The hamster spent less time smelling the side of the known smell = Habituation

The hamster spent more time smelling the side of the unknown hamster smell = Dishabituation

Why have researchers explore habituation circuity of primitive invertebrates instead of humans?

• Have fewer neurons

• simpler reflex circuits

• neurons are larger

Habituation in Aplysia (snails)

The reflex of snails retracting their gills became smaller and smaller (eventually stopped) as researchers kept touching (brushing) their siphon

What was occurring with the firing of neurons in the Habituation of Aplysia (snails)

The Interneuron was not relaying the signals of the brush on the snails siphon

What happened in the Sensitization of Aplysia (snails)?

researchers applied a shock to the snail while simultaneously brushing the snail siphon and snail retracted its gills.

In habituation, do sensory neurons still have action potentials?

Yes

Is habituation LTP or LTD?

Habituation is Long term depression because it causes a lack of connections