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Intrinsic Motivation: Internal drives that lead to engagement in activities due to enjoyment, purpose, growth, and curiosity.
Extrinsic Motivation: External incentives that encourage behavior, including winning, perks, prizes, and future success.
Connection: These forms of motivation can be referenced in the context of Maslow's hierarchy of needs, which outlines human motivation based on fulfilling basic needs before moving to higher levels.

Glycogen: A finite source of energy; primarily used for quick energy.
Triglycerides: An unlimited energy source; primarily used for long-term energy storage.

Anabolic State: The state of the body when it is active in storing energy and converting it into glycogen and triglycerides while eating.
Catabolic State: The state of the body after eating, where it utilizes stored energy sources.

Proposes that the brain maintains a predetermined set point for energy storage, suggesting a connection between body fat levels and brain functioning.
- Predetermined Weight Range: The body strives to maintain a specific weight range, which is genetically influenced.

An experiment involving genetically obese mice lacking both copies of the Ob gene demonstrated that this gene is responsible for relaying information to the brain regarding the state of fat stores.
- This was validated through parabiosis, a method where an obese mouse and a normal mouse are connected to share blood supply, resulting in a balanced metabolism.
The hormone Leptin:
- Decreases appetite and increases energy expenditure by communicating with the hypothalamus.

Function: Vital for maintaining homeostasis in the body; monitors temperature, salt levels, and manages hormonal responses to feedback mechanisms.
Location: Situated around the third ventricle, directly above the pituitary gland.
Structure: Three main areas within the hypothalamus:

Lateral Region:
- Function: Promotes eating.
- Impact of Lesion: When this pathway is damaged, it leads to anorexia in mice.
Ventromedial Region:
- Contains the arcuate nucleus.
- Function: Suppresses eating behavior.
- Impact of Lesion: Lesioning this area results in obesity in mice.
Paraventricular Region:
- Role: Controls the pituitary gland and autonomic nervous system (ANS).

After meals, leptin increases, activating neurons in the arcuate nucleus (within the ventromedial hypothalamus).
- This activation is stimulated by bloodborne insulin.
Key Neurons:
- α-MSH neurons:
- Function: Activate the paraventricular nucleus to stimulate pituitary hormones, which increase metabolism and sympathetic responses.
- Inhibition of Feeding: By projecting to the lateral hypothalamus, these neurons inhibit further feeding, creating a feeling of satiety.
If not full: Leptin signaling decreases, leading to the activation of alternative neurons in the arcuate nucleus stimulated by Ghrelin.
AgRP Neurons:
- Function: Inhibit paraventricular neurons that control sympathetic ANS activation and stimulate feeding by activating neurons in the lateral hypothalamus.
Gastric Distension: Can measure satiety and stimulate the nucleus of the solitary tract.

Reward/Reinforcement Mechanism: Can be self-stimulated, primarily occurring in areas with dopamine release.
Dopamine Neurons: Located in the Ventral Tegmental Area (VTA) and important for the reinforcement process rather than just initiating motor functions.

When drugs are consumed, there is a significant dopamine release in these neurons; however, research shows dopamine is not a "pleasure molecule."
- Experiment: Rats still exhibited positive responses toward pleasurable stimuli even after dopamine neurons were destroyed, indicating dopamine's role in learning and wanting rather than pure pleasure.

Distinction: While dopamine is present in normal wanting behavior, only a few brain regions are responsible for generating actual pleasure.
- Implication: This difference is crucial in understanding drug addiction, as severe addiction stems from an imbalance in the desire (wanting) rather than the enjoyment (liking) of the drug.

James-Lange Theory:
- Emotions arise in response to physiological changes in the body.
  - Example: A human sees a snake, realizes they should feel fear; spinal cord injuries can blunt emotional responses.
Cannon-Bard Theory:
- Emotions can occur independently of physiological changes.
  - Example: A human sees a snake, knows to feel fear, and experiences the emotion without any physical changes.
  - Supporting Evidence:
  - Bridge Experiment: Suggested that emotion can be misinterpreted based on context.
  - Injection Experiment: Individuals given epinephrine reported higher levels of anger compared to those receiving saline; this could also hold true for happiness conditions.

Function: Processes emotions, memory, and motivation.
Structure: Forms a ring around the center of the brain.
- Components:
- Cingulate Gyrus: Involved in processing prosocial learning, decision-making, and pain; connected to many subcortical regions.
- Hippocampus: Critical for memory formation and spatial navigation.
- Amygdala: Responsible for fight-or-flight response, comprised of three subdivisions (basolateral, corticomedial, and central nucleus) that are highly sensitive to fear and also engage in learning aggression.

The hypothalamus contributes to motivation and aggression, capable of initiating an aggressive response independently.
It can trigger fixed action patterns associated with positive emotions, such as smiling.

Dorsolateral Cortex: Focused on executive functions.
Anterior Cingulate Cortex: Involved in affect regulation and motivation.
Orbitofrontal Cortex: Affects mood and behavior; essential in distinguishing context prior to emotional experiences.

The concept of the limbic lobe was proposed by Paul Broca.
Later, James Papez introduced the idea of an emotional circuit system involving the limbic structures.

Discrete Emotions Theory: Proposes that humans are innately programmed with 5-6 basic emotions that are conserved across various species and cultures.