BIOL1002 Lecture Notes - Lecture 12: Frontal Lobe, Libido, Sexual Stimulation
WEEK 12
MOTIVATION AND EMOTION
Motivation – behaviour that seems purposeful and goal-directed
Emotion – Cognitive interpretation of subjective
• Tumours intruding into hypothalamus can make people continuously experience hunger
– the nervous system produces hunger-oriented behaviours
• Some behaviours are rewarding and some are aversive
• To understand behaviours, we must examine neural activity
Causes of Behaviour – Sensory Deprivation
• Brain has an inherent need for stimulation
• Most participants were content for 4ish hours, but then started to crave ANY stimulation
• Distresses, few lasted more than 24 hours
• In absence of stimulation, brain will see it out!
Evolutionary influences on behaviour
• Innate Releasing mechanism (IRM)
- Inborn, adaptive responses that improve an animal’s survival
- Aid feeding, reproduction and escape
- Present from birth (innate)
- Maintained in the genome of species
- IRMS are triggers for innate behaviours
Example : kittens shown the ‘Halloween’ posture of a cat responds as though
threatened (arched back, bared teeth), even though they have never had
exposure to another adult cat
• IRM in Humans
- Adult performed exaggerated facial expressions
- Babies responded by imitating?
- Newborns are too young to intentionally imitate
- More likely that babies are matching the expressions to internal templates
- Adult expressions trigger some internal program to reproduce the expressions
- Facial expressions are important to human communication – adaptive
B f skinner
• Experience shapes behaviour by pairing stimuli and consequences
• Many complex behaviours are learned
find more resources at oneclass.com
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• Some events act as rewards to reinforce behaviour, increasing the likelihood of the
behaviour recurring
• Reinforcement can produce complex behaviours
• Argued against idea that behaviour is under our own control
• Learned taste aversion- taste of a certain food paired with illness, brain wires to associate
the two
Preparedness
• Brain is prewired to make certain types of associations but not others
• Biological preparedness – inherently inclined to form associations between certain stimuli
and responses
• Phobias also are easily formed associations through classical conditioning
• Serves as an evolutionary adaption to avoid danger
• Example of easily learned association is taste aversion
- Taste aversion: Garcia
Rats developed aversion to water consumed prior to being irradiated
3 groups given sweetened water followed by:
i. No radiation
ii. Mild radiation
iii. Strong radiation
Given a choice between sweetened water and regular tap water, rats who had
been exposed to radiation drank much less sweetened water than those who
had not (80% less)
Taste aversion does not require cognitive awareness – do not have to
consciously recognize a connection between perceive cause (the taste) and
effect (the negative feeling)
REGULATORY AND NON-REGULATORY BEHAVIOURS
Regulatory Behaviours
• Behaviours motivated by survival
• Controlled by homeostatic mechanisms
• Homeostatic mechanisms act at the level of the cell, tissue, organ and organism
• Homeostatic mechanisms maintain critical body functions within a fixed range
- Example: hypothalamus holds body temperature constant at 37O
If this falls, neural circuits respond by initiating systems that increase
temperature (shivering, seeking a heat source)
find more resources at oneclass.com
find more resources at oneclass.com
Non-regulatory Behaviours
• Behaviours not required to meet survival needs
• Some involve the hypothalamus (sexual behaviours) but most do not
• Involve mainly forebrain structures (frontal)
- Example: sex, parenting, food preferences, aggression, reading, exercising, watching
television, delivering lectures.
NEUROANATOMY OF MOTIVATED AND EMOTIONAL BEHAVIOUR
Neuroanatomy
• Neural circuitry involved in emotion and motivation encompasses several different
regions
• The expression of emotion involves many physiological changes including:
- Heart rate
- Motor responses
- Blood pressure
- Movement of facial muscles
- Hormone secretions
- Tear production
Neuroanatomy of Motivated Behaviour
• Critical Structures
- Hypothalamus and pituitary gland
- Limbic system
- Frontal lobes
• Homeostatic mechanism
- Process that maintains critical body functions within a narrow, fixed range
Types of motivated Behaviours
REGULATORY
NONREGULATORY
Motivated to meet basic survival needs
NOT motivated to meet basic survival needs
Controlled by homeostatic mechanisms
NOT controlled by homeostatic mechanisms
Involves the hypothalamus
Most involve frontal lobes more than
hypothalamus
Example: eating, drinking, body temperature
Example: Sex, food preference, curiosity
Both project to the hypothalamus
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Motivation behaviour that seems purposeful and goal-directed. Emotion cognitive interpretation of subjective: tumours intruding into hypothalamus can make people continuously experience hunger. The nervous system produces hunger-oriented behaviours: some behaviours are rewarding and some are aversive, to understand behaviours, we must examine neural activity. Causes of behaviour sensory deprivation: brain has an inherent need for stimulation, most participants were content for 4ish hours, but then started to crave any stimulation, distresses, few lasted more than 24 hours. In absence of stimulation, brain will see it out! Inborn, adaptive responses that improve an animal"s survival. Example : kittens shown the halloween" posture of a cat responds as though threatened (arched back, bared teeth), even though they have never had exposure to another adult cat. Newborns are too young to intentionally imitate. More likely that babies are matching the expressions to internal templates. Adult expressions trigger some internal program to reproduce the expressions. Facial expressions are important to human communication adaptive.
