Brainstem: Medulla & Pons

Brainstem: Medulla & Pons

Reticular Formation

Thalamic Pain SyndromeThalamic Pain Syndrome

Thalamus

Cerebellar ataxia Ataxic Gait

• Cerebellum = “little brain”

• helps us judge time

• nonverbal learning/memory

• discriminate sounds/textures

• coordinate voluntary movement

Limbic System

• 1. Hypothalamus

• 2. Amygdala

• 3. Hippocampus

Hypothalamus: Where is it?

1. Hypothalamus

• Subdivided into different functional areas• Involved in the regulation of:

– Hunger– Thirst– Body temperature– Sexual behavior

• Contains “reward” centers (pleasure centers) (Olds/Milner)

• Reward centers often release dopamine• Addictive behaviors: “reward deficiency syndrome”?

Functional Areas of the Hypothalamus

2. Amygdala

Amygdala

Amygdala• Two structures, right and left

– Each is the size of a lima bean– Sit posterior to the hypothalamus

• Perception of fear and aggression• Processing emotion-laden memories• Kluver & Bucy

– Destroyed amygdala in monkeys• Ill-tempered to mellow

– Stimulate amygdala: • 1 spot, extreme aggression• Another spot, extreme fearfulness

Kluver-Bucy Syndrome• 1. Psychic blindness (inability to recognize familiar objects)• 2. Hypermetamorphosis (strong tendency to react to visual

stimulus)• 3. Increased oral exploration (putting things in the mouth)• 4. Placidity (marked decreased fear response)• 5. Indiscriminate hypersexuality• 6. Hyperphagia/Eating nonfood items

3. Hippocampus

Hippocampus

• Involved in memory formation (names, images, events)

• Memories formed but not stored• Very active during sleep; memories are

processed and filed for later retrieval• Left hippocampus: memories of verbal

information• Right hippocampus: memories of visual

information and locations

Damage to the Hippocampus