Parts of the Forebrain

Thalamus: active gatekeeper filtering/prioritizing sensory info reaching conscious awareness — not just a passive relay. Smell bypasses most of the thalamus.
Hypothalamus sub-regions: lateral = hunger/feeding ON, ventromedial = satiety/feeding OFF, anterior = temperature regulation + reproductive behavior.
Posterior pituitary reached by direct neural connections (stores ADH, oxytocin made by hypothalamic neurons); anterior pituitary reached only via the hypophyseal portal system (blood vessels), no direct neurons.
Basal ganglia regulate movement selection, posture, muscle tone, and automaticity of practiced movement (extrapyramidal motor system); Parkinson's = substantia nigra dopamine neuron loss.
Limbic system: septal nuclei (reward network), amygdala (tags emotional significance), hippocampus (memory consolidation, spatial memory, connects via fornix), anterior cingulate cortex (integrates emotion with thought/error detection).
4 cortical lobes: frontal (executive function, prefrontal cortex, primary motor cortex, Broca's area), parietal (somatosensory cortex, spatial awareness), occipital (visual cortex), temporal (auditory cortex, Wernicke's area, hippocampus).
Hemispheres: contralateral organization = each hemisphere controls/senses the opposite body side; lateralization = functional specialization (language/sequential = left, spatial/prosody = right); bilateral organization = shared input (e.g., hearing).

Hypophyseal portal system: Blood vessel network carrying releasing/inhibiting hormones from the hypothalamus to the anterior pituitary only.
Anterograde amnesia: Inability to form NEW long-term memories going forward; classically linked to hippocampal damage.
Retrograde amnesia: Inability to retrieve OLD memories formed before an injury.
Prefrontal cortex: Frontal lobe region for self-regulation — stopping to think, weighing consequences, adjusting behavior.
Spatial neglect: Parietal lobe damage syndrome where a person behaves as though one side of the world doesn't exist, despite normal vision.
Contralateral organization: Each hemisphere communicates primarily with the opposite side of the body (motor + sensory).
Prosody: Emotional tone, rhythm, and emphasis of speech; processed mostly in the right hemisphere.

Broca's Area (Frontal Lobe)	Wernicke's Area (Temporal Lobe)
Governs speech production	Governs language comprehension
Damage → halting, effortful speech	Damage → fluent speech that doesn't make sense
Comprehension stays intact	Production stays fluent

Lateral Hypothalamus	Ventromedial Hypothalamus
Hunger/feeding "on" switch	Satiety/feeding "off" switch
Damage decreases appetite	Damage linked to overeating/weight gain (animal studies)

Contralateral Organization	Lateralization
About body SIDE — which hemisphere controls/senses which side	About FUNCTION — which hemisphere specializes in which task
Damage → symptoms on opposite body side	Left = language, sequential processing; right = spatial awareness, prosody

Lateral vs. ventromedial hypothalamus sit next to each other but do opposite jobs — easy to swap under pressure.
Hypophyseal portal system serves the anterior pituitary ONLY — posterior pituitary is reached by direct axonal connections, no portal system involved.
"Left-brained/right-brained" personality types are a popular misconception — hemispheres have real specializations but are deeply interconnected via the corpus callosum, not independent personality centers.

Which hormones are stored/released by the posterior pituitary, and where are they made?

What is the key difference between anterograde and retrograde amnesia?

Which limbic structure connects to other limbic structures via the fornix and is central to memory consolidation?

Which hemisphere specialization handles prosody and spatial awareness?

What structure connects the two cerebral hemispheres?

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