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Lecture Notes
Chapter 13
Chapter 13 (and Related) Lecture Notes
Motivation
Strength of behaviour
Persistence of behaviour
Tied up with reinforcement and punishment
Biological Drives
- Food, water, air, trace elements, protection
- Maintain homeostasis
- Some other purpose
Regulatory System
Set point (optimum value for the system)
Detector (monitors system variable)
Correctional mechanism (restores system to set point)
Feedback
Physiology and Drives
Drive Reduction Hypothesis of Reinforcement
Physiological changes
- Produce a state/drive
- Act on the drive (behaviour)
- Drive reduction (reinforcement)
- Hard to measure drive
- Many behaviours produce excitement...drive increasing
Drives as Brain States
Neural activity in different sets of neurons
Central drive system
- Neural circuits involved in drive
- Signals to raise and lower drive
- Perception, cognition, motor
Central-State Theory
Hypothalamus as Hub of Central Drive System
Tracts to many brain areas
Linked to autonomic system
Hormones
- Sensitive to
- Controls release of
Hypothalamic Control of Hunger
- Food seeking when neurons active
- Bilateral lesions...starvation
- Electrical stimulation...eat
- Satiety center when neurons active
- Bilateral lesions...obesity
- Electrical stimulation...donšt eat
- From ventromedial to lateral area
Hypothalamus of Rat
Sexual Behaviour
- Testes, ovaries
- Promote reproduction
- Influence behaviour
- Motivation
- Testosterone and others
- Organizational effects
- Prenatal
- Activational effects
- Male sexual development
- Sex organs, brain
- Environmental effects
- Change androgen secretion
- Sex drive
- Men and women
- Estrous cycle
- Menstration
- Sexual receptivity
- Social function
- Sex hormones at puberty
- Heterosexual and homosexual behaviour
- Homosexuality in non-human animals
- Not due to hormone imbalances
- Could be pre-natal hormonal influences
- Environmental theories
- Now seen as less influential
- Biological theories
- Genetic components
- Twin studies