Major Brain Structures & functions

3 primary sulci

sagittal sulcus: logitudinal fissure

central sulcus: sulcus of Rolando

lateral sulcus: Sylvian fissure

longitudinal fissure / sagittal sulcus

crevice that divides the brain into 2 cerebral hemispheres

sulci

the sunken, concave furrows of the cerebral cortex (i.e., outside layer of the brain)

calcarine sulcus

divides primary visual cortex into:

• cuneus

• lingual gyrus

gyri

the convex ridges of the folds of the outside layer of the brain (i.e., cerebral cortex)

landmarks of the cerebrum

• 5 lobes

• limbic system/lobe

• subcortical structures

Cerebral cortex

where important lobes and association areas are located; the outside layer of brain

the 5 lobes

frontal, parietal, occipital, temporal, insular

the frontal lobe is located—

at the front of the brain, anterior to central sulcus (sulcus of Rolando)

superior to lateral sulcus (Sylvian fissure)

the frontal lobe contains—

• motor cortex (including primary motor cortex)

• prefrontal cortex

frontal lobe functions:

• head & body movement (motor)

• decision-making, planning, pursuit of long-term goals, impulse control (prefrontal)

• executive functions

• working memory

• social skills & personality

• speech production (Broca’s)

Broca’s area is located in—

Frontal lobe, usually leftside brain

Cental sulcus

fold that separates the frontal lobe from the parietal lobe

the parietal lobe is located—

at the top of the brain

• posterior to central sulcus (sulcus of Rolando)

• superior to lateral sulcus (Sylvian fissure)

parietal lobe functions:

Multimodal sensory center

• primary somatosensory cortex:

  • processing somatosensory information (sensations from body)

    • touch

    • thermal

    • visual-spatial processing/ proprioception

• superior parietal lobe: attention mechanisms

• inferior parietal lobe: language

  • verbal working memory

  • word reading & comprehension (phoneme-grapheme corr.), writing, number manipulation, semantic processing

• association areas (“where”)

the occipital lobe is located—

at the very back of the brain

occipital lobe functions:

• main area for visual processing (primary visual cortex)

• association areas (“what”)

where is the primary somatosensory cortex located?

parietal lobe

where is the primary visual cortex located?

occipital lobe

the temporal lobe is located—

on the sides of the brain, inferior to lateral sulcus (Sylvian fissure)

temporal lobe functions:

PRIMARY LANGUAGE AREA

• hearing (primary auditory cortex)

• object & face recognition

• learning

• hippocampus: short & longterm memory

• language reception & comprehension

• processing of colors, shapes, numbers

• association areas (“What”)

the primary auditory cortex is located—

in the temporal lobe

Wernicke's area is located—

between the temporal & parietal lobes

Wernicke’s area functions:

language comprehension

the cerebellum functions:

major roles in movement

• motor coordination & control

• balance & posture

• fine-tuning of voluntary movements

• movement-related learning

the brainstem is divided into:

midbrain, pons, medulla

medulla (oblongata) is located—

just above the spinal cord, at the bottom of the brain stem

medulla functions:

regulation of vital functions (e.g., cardiovascular, repiratory)

pons functions:

• pathways that carry info to and from cerebellum

• houses a group of nerves involved in sensory and motor functions of head & face (cranial nerves)

midbrain functions:

contain 2 largest dopamine-producing areas in brain

• substantia nigra: dopamine neurons for movement (damage= Parkinson’s)

• ventral tegmental area (VTA): dopamine neurons extending to various parts of brain

  • ㄴ⭐ nucleus accumbens: VTA-nucleus accumbens pathway is crucial for rewarding experiences (food, sex, addictive drugs)

substantia nigra & nucleus accumbens are part of

basal ganglia

the thalamus is located—

above the brainstem

basal ganglia functions:

• movement

• habit formation

• reward processing

etc.

thalamus functions:

relay station transmitting neural impulses from different receptors to the cerebral cortex

ex)

all sensory info except olfaction ➡ specialized nuclei of thalamus ➡ cortex

pineal gland is located—

posterior to the thalamus

pineal gland functions:

secretes melatonin hormone

ㄴ melatonin: secreted mostly during darkness; regulates circadian rhythms

hypothalamus is located—

right below the thalamus

hypothalamus functions:

homeostasis 유지하느라 ㅈㄴ 일이 많은 애임

regulates:

thirst & drinking bx

hunger & feeding

body temp

stress responses

circadian rhythms

+++++

sends signals to 바로 밑 pituitary gland, to produce hormones

• growth

• thyroid-stimulating

• follicle-stimulating

• luteinizing hormone

++++++

makes oxytocin & vasopressin and sends them to pituitary gland to secrete in bloodstream

the hippocampus is located—

in the temporal lobe

hippocampus functions:

memory, especially STM ➡ LTM tranfer

amygdala is located—

adjacent to the hippocampus

amygdala functions:

• processing fear

• fight/flight rsponse

***also involved in positive emotions like pleasure

corpus callosum functions:

connects left & right cerebral hemispheres (sides of the brain), enabling cross-communication

largest bundle of axons in the brain

cerebral ventricles

hollow cavities in the brain, that have special membranes producing cerebrospinal fluid (CSF)

CSF (cerebrospinal fluid) functions:

surrounds brain in a protective layer

reduces strain forces (gravity, inertia) by suspending the brain

removes waste products from brain

helps regulate extracellular environment of neurons

Ventral stream

“what” pathway

Dorsal stream

“where” pathway