Chapter 12: Motivation to Learn Flashcards
Exploration
Most animals explore new environments
Food, water, shelter, possible dangers must be sought out and evaluated
Recall open field activity in mice
Play
Seen in many mammalian species, especially K-selected
Defined as inefficient behaviour without apparent immediate direct benefit or clear goals
Play
Cost vs benefits
Costs:
Energy expenditure
Risk of injury
Possibly attract predator attention (make noise)
Benefits:
Strengthens muscles
Potentiates social learning (competition, emotional expression, multiple skill acquisition)
Expression of Play
- monkeys
- humans
Rhesus monkeys display a ‘play face’ before engaging in aggressive rough and tumble play
Posturing, wrestling, chasing, and avoidance serve as practice for adult life
Some primates (especially humans) incorporate tool use in play
In humans, playfighting in children involves evolutionary conserved tactics like pinning, kicking, hitting, grappling, etc.
However, modern adult human fights often include weaponry
Humans only species to play in teams
Lesioning what area of the brain will cause reduced play behaviour
Lesioning the ventromedial hypothalamus (VMH) will reduce play
Large lesions to the hippocampus, the amygdala, the cerebellum, the lateral hypothalamus will all reduce play behaviour
Electrical Brain Stimulation
Electrodes implanted in brain core
Rats prefer regions of cage where electrodes deliver mild pulses to brain
Animals work for brief pulses of electricity contingent on response
Very high rates of response
Can exclude or stimulate feeding, drinking
Rapid extinction
Physiology of Electrical Brain Stimulation
Various sites effective –Some interact with food and water deprivation
Highest rates in lateral hypothalamus, region traversed by the medial forebrain bundle (MFB)
Anti-dopamine drugs block reinforcement
- VTA–>MFB–>Nucleus Accumbens
- Lesion MFB =do not see this reward behaviour
Physiology of Reinforcement
Consummatory behaviour (eating, drinking, sex) associated with increased dopamine activity in nucleus accumbens Electrical brain stimulation in medial forebrain bundle also associated with increased dopamine activity in nucleus accumbens
Intense Emotions Enhance Memory
Memories of traumatic and/or exciting events are more intense and durable Stress hormones (ACTH, cortisol, adrenaline) given during learning can enhance memory
Physiology of Emotional Memory
Cortisol
Glucocorticoid receptor in hippocampus and amygdala
Activation of glucocorticoid receptors (during emergency stress responses) facilitate memory consolidation
Sustained activation (during chronic stress) leads to hippocampal atrophy and memory deficiency
Physiology of Emotional Memory
Adrenaline
- Glucose Hypothesis
Adrenaline leads to liberation of energy and glucose production
Neural cells indirectly influenced by excess glucose, specifically hippocampus which needs lots of energy in memory consolidation
Physiology of Emotional Memory
Adrenaline
- Peripheral Receptors and Amygdala
Adrenaline stimulates afferents of the vagal nerve which signals to nucleus of the solitary tract (NTS) in medulla oblongata
Noradrenaline neurons from the NTS project to the basolateral amygdala and releases NE, which enhances memory via actions on hippocampus
Primary Reinforcer
A stimulus that naturally rewards behaviour
food, water, sexual partner, increased comfort
Conditioned Reinforcer
A formerly neutral stimulus that acquires a capacity to reward behaviour through a history of pairing with primary reinforcement
Intrinsic rewards and punishers
natural consequences of behaviour
- Sweet foods, sleep (physiologically beneficial)
