BIOL 361 Lect: Brain and Cranial Nerves

Frontal lobe

Frontal bone to central sulcus

Cognition, speech, and motor control

Parietal lobe

Central sulcus to parieto-occipital sulcus

Interprets signals of general senses and taste

Occipital lobe

Parieto-occipital sulcus to occipital bone

Principal visual center

Temporal lobe

Temporal bone to lateral sulcus

Hearing, smell, learning, and memory

Insula

Deep to lateral sulcus

Taste, visceral sensation, and language

Cerebellum

Back of the brain, develops from metencephalon

Coordination and communication center

Gray matter

Located on the cortex of the cerebrum and cerebellum

Neuron communication occurs here

White matter

Deep in brain

Composed of axons and tracts (bundles of myelinated axons)

Dura mater

Tough, outermost layer

Arachnoid mater

Transparent, middle layer

Pia mater

Delicate, inner layer

Brainstem

Crucial for survival functions and cranial nerve origins

Thalamus

Makes up 4/5 of diencephalon

Involved in sensation, movement, memory, and emotion

Hypothalamus

Extends from optic chiasm to mammillary bodies, develops from the diencephalon

Controls ANS and endocrine system: hormone secretion, heartrate, blood pressure, thermoregulation, hunger, circadian rhythm, sex drive, and memory

Pineal gland

Endocrine gland that produces melatonin; regulates sleep cycle

Pituitary gland

Corpus callosum

Hippocampus

Inferior to the fornix

Part of the limbic system involved in long term memory

Amygdala

Anterior to the hippocampus

Involved in emotion processing and learning

Pons

Connects the cerebrum and cerebellum, develops from the metencephalon

Regulates breathing and fine tunes it; contains cranial nerves for the face, eyes, hearing, and balance

Medulla oblongata

Extends from the foramen magnum to pons, develops from the myelencephalon

Regulates heartrate, blood pressure, respiration, and reflexes such as swallowing and coughing

Midbrain

Part of the brainstem that connects the forebrain to the hindbrain, develops from the mesencephalon

Involved in visual and auditory reflexes, regulates movement through dopamine, controls eye movement through cranial nerves III and IV

Cerebrum

Largest part of the brain, develops from the telencephalon

Involved in higher brain functions

Prosencephalon

Embryonic nervous system; forebrain

Mesencephalon

Embryonic nervous system; midbrain

Rhombencephalon

Embryonic nervous system; hindbrain

Blood-brain barrier

Seals capillaries in brain tissues

Highly permeable to alcohol, caffeine, nicotine, anesthetics

Not permeable to antibiotics or cancer drugs

Lateral ventricle

Present in each hemisphere of the cerebrum; connected by the interventricular foramen

Involved in CSF production and circulation

Third ventricle

Located near thalamus, beneath the lateral ventricles

Circulates CSF to the fourth ventricle

Fourth ventricle

Between the brainstem and cerebellum

Circulates CSF to the central canal and subarachnoid space around CNS

Cerebrospinal fluid (CSF)

Produced by the choroid plexus

Provides buoyancy, chemical stability, and rinses metabolic waste