PSYC*2330 Chapter 2: Elicited Behaviour, Habituation, and Sensitization Flashcards
What is a reflex?
A close relation between a stimulus and a response mediated by a neural circuit
What is the simplest elicited behaviour?
A reflex
Descartes’ belief that sensory inputs and motor outputs used the same nerves was disproven by which finding?
If sensory input was cut, motor output remains and if motor output was cut, sensory input remains
Descartes’ belief that reflexes were mediated by animal spirits released by the pineal gland was disproven by which finding?
That nerves can function independently of brain input
Descartes’ belief that animal spirits enlarge muscles for contraction was disproven by which finding?
That gasses do not expand muscle size (a contracted muscle has the same volume as a relaxed muscle)
T or F: Simple reflexes cannot be influenced by higher nervous system activity
False
T or F: Stimuli always elicit reflexes.
False. Almost always, but not every time.
Does the vigour of a response necessarily reflect the intensity of the releasing stimulus?
No
T or F: A stimulus can release the inhibition of a response.
True
T or F: All reflexes are innate.
False. New reflexes can be learned through associations.
T or F: Responses to stimuli can change as a result of experience.
True
What represents the fewest neural connections necessary for a reflex action?
The reflex arc
What three neurons form the reflex arc?
- Sensory neurons
- Interneurons
- Motor neurons
What are sensory neurons also referred to as?
Afferent neurons
What are motor neurons also referred to as?
Efferent neurons
What are modal/fixed action patterns?
Complex patterns of behaviour shared between members of a species
Are modal action patterns instinctual or learned?
Instinctual
T or F: Modal action patterns can be very complex and occur over an extended period of time.
True
What is a sign stimulus?
A specific feature of an object or animal that elicits a modal action pattern
What is a supernormal stimulus?
An exaggerated sign stimulus
What did William James propose about the psychology of instincts?
Instincts can be overridden by experience and each other, as many instincts are already in conflict
How do the principles of psychology and biology define instincts differently?
- Psychology: Instincts are motivators of behaviour
- Biology: Instincts are behaviours
In chicks, the tectofugal pathway is essential for what?
The recognition of colours, shapes, and the motions of objects
In chicks, the thalamofugal pathway is important for what?
Visual learning
What are appetitive behaviours?
Searching behaviours that serve to bring an organism into contact with a sign stimulus
T or F: Appetitive behaviours are not flexible.
False
What are consummatory behaviours?
Behaviours that serve to bring about consummation or completion (usually modal action patterns)
T or F: Distinct brain areas manage appetitive and consummatory behaviour.
True
T or F: Instincts can be appetitive or consummatory.
True
Which two processes can be triggered by repeated stimulation?
- Habituation
- Sensitization
What is habituation?
A decrease in an elicited behaviour due to repeated presentations of the eliciting stimulus
T or F: Habituation is both stimulus and response specific.
True
What is a variable that influences the rate of habituation?
Attention to the stimulus
What is dishabituation?
The restoration of a habituated response to full strength
Does a dishabituating stimulus need to elicit a response itself in order to change the habituated response back to normal?
No
In terms of habituation to visual stimuli in infants, did habituation occur faster to complex or simple stimuli?
Habituation occurred faster to simpler stimuli
When presented with complex stimuli, what was the pattern of habituation showed by infants?
They had an initial increase in attention followed by slower habituation
When habituated to simple stimuli, do babies became dishabituated after being presented with more complex stimuli or less complex stimuli?
More complex stimuli, but not less complex stimuli, caused dishabituation
What is spontaneous recovery?
the return of responding to baseline levels produced by a period of rest after habituation or sensitization
What are two ways in which dishabituation can occur?
- Novelty of the stimulus
- Delay in receiving stimulus
What long-term habituation?
Habituation that occurs when stimuli are presented widely spaced in time
What is short-term habituation?
Habituation that occurs when stimuli are presented very closely in time
Do repeated presentations of a stimulus always result in both long-term and short-term habituation?
No
In terms of spontaneous recovery, how do long-term and short-term habituation differ?
- Long-term: Responses can be restored to some extent, but spontaneous recovery is never complete
- Short-term: Spontaneous recovery occurs following a period without stimulation
What is sensitization?
An increase in an elicited behaviour due to repeated presentations of the eliciting stimulus or from exposure to a strong extraneous stimulus
What is sensory adaptation?
A temporary reduction in the sensitivity of sense organs caused by repeated or excessive stimulation
What is response fatigue?
When a reflex does not occur due to fatigue causing incapacitation of effector muscles
What is the main way in which sensory adaptation and response fatigue differ from habituation?
- Sensory adaptation and response fatigue: Occur outside the nervous system in sense organs and receptors
- Habituation: Process occurs within nervous system
In terms of attention, why are habituation and sensitization particularly useful?
They facilitate the direction of attention toward stimuli that are presumably more important in certain scenarios
T or F: Regardless of their intrinsic meaning, threatening cues prompt somatic and autonomic reactions of defence.
True
T or F: Fear does not sensitize the startle response.
False
Which theory assumes that different types of underlying neural processes are responsible for increases and decreases in responsiveness to stimulation?
The dual-process theory
T or F: According to the dual-process theory, habituation and sensitization are mutually exclusive.
False
According to the dual-process theory, habituation and sensitization are the result of what?
The sum of both habituation and sensitization processes
What is the stimulus-response system?
The shortest neural pathway that connects eliciting stimuli and elicited responses (can be viewed as the reflex arc)
T or F: Each eliciting stimulus activates the S-R system and causes a build-up of habituation.
True
Where is habituation assumed to occur?
The stimulus-response system
What is the state system?
Neural structures that determine the general level of responsiveness/arousal of the organism
Where is sensitization thought to occur?
The state system
In terms of their activation, how do the stimulus-response system and state system differ?
- S-R system: Activated with every eliciting stimulus
- State system: Only activated by arousing events
When tested with quiet background noise, did rats habituate or sensitize their startle response?
Quiet background noise habituated startle response
When tested with loud background noise, did rats habituate or sensitize their startle response?
Loud background noise sensitized the startle response
What is the opponent process theory of motivation?
The assumption that the mechanisms involved in emotional behaviour serve to maintain emotional stability
What are the three characteristics of emotional reactions at the core of the opponent process theory of motivation?
- Emotional reactions are biphasic
- The primary reaction becomes weaker/ habituates with repeated stimulation
- The weakening of the primary reaction is accompanied by the strengthening of the after-reaction
Which process in the opponent process theory is elicited by a biologically significant stimulus?
The primary process/ a process
What is the opponent process/ b process?
A compensatory mechanism that occurs in response to the primary process
T or F: The opponent process causes changes opposite of those caused by the primary process.
True
According to the dual-process and opponent-process theories, do effects always reflect the combined processes that caused them?
Not necessarily
T or F: When a stimulus is first presented, the a process occurs unopposed by the b process, allowing the reaction to reach its peak.
True
What happens when an initial stimulus is withdrawn and the a process returns to baseline?
There is nothing to oppose the b process, so its opponent effect becomes evident
How does the opponent process theory explain why familiar stimuli don’t elicit strong reactions when presented, but have much stronger after-reactions when removed?
The theory assumes that the b process becomes strengthened with repeated use
What happens when the mantle or siphon of an aplysia is touched?
A reflexive withdrawal response is elicited
How is the fact that habituation is stimulus specific demonstrated using aplysias?
Repeatedly touching the siphon has no effect on the gill reflex elicited by touching the mantle, and vice versa
Does a slight shock to the tail of an aplysia enhance the gill reflex in response to touching the mantle. siphon, or both?
Both
What is the physiology behind habituation?
Repeated stimulation inactivates some Ca2+ channels which reduces the amount of Ca2+ entering the cell, resulting in less transmitter being released and a weaker response
What is the physiology behind sensitization?
Sensitization engages the interneurons, which causes increased neurotransmitter release and a stronger response
What is the physiological consequence of long-term habituation?
Reduced synaptic connections
What is the physiological consequence of long-term sensitization?
Increased synaptic connections
T or F: Habituation and sensitization are limited in their capacity to predict outcomes.
True
