The Forebrain

forebrain

largest and most complex region of the brain (~90% of the brain) composed of the cerebral cortex and limbic system; also called cerebrum

cerebral cortex

wrinkled outer portion ("bark") of the forebrain consisting of the left and right cerebral hemispheres; contains the most sophisticated centers for brain functioning; ~1/4" thick "gray matter" which is mainly glial cells and neurons

cerebral hemispheres

portion of the cerebral cortex (either left or right) with four regions: temporal lobe, occipital lob, parietal lobe, and frontal lobe; connected by the corpus callosum

corpus callosum

thick bundle of nerve fibers/axons that connect the two cerebral hemispheres, allowing both sides to communicate with each other

temporal lobe

part of the cerebral hemisphere near the temples and receives auditory information; contains the primary auditory cortex

occipital lobe

part of the cerebral hemisphere at the back that receives visual information; contains the primary visual cortex

parietal lobe

part of the cerebral hemisphere above the temporal lobe that deals with bodily/somatic sensations; contains the somatosensory cortex

frontal lobe

largest part of the cerebral hemisphere that deals with voluntary movements, thinking, planning, & control of emotions; contains the primary motor cortex

limbic system

group of forebrain structures that form a border around the brainstem (beneath the cerebral cortex); involved in emotion, motivation, learning, and memory; 4 key structures: hippocampus, thalamus, hypothalamus, amygdala

hippocampus

large structure in the temporal lobe in both hemispheres; forms new memories

thalamus

rounded mass of cell bodies within both hemispheres; processes and relays sensory information to the cerebral cortex (except for smell), regulates attention, awareness, motivation, and emotional sensation

hypothalamus

peanut-sized area below the thalamus that links the brain and endocrine system and contains 40+ neural pathways; "the brain within the brain"; includes the autonomic nervous system and the suprachiasmatic nucleus; deals with hunger, thirst, sleep, and sexual behavior

autonomic nervous system

part of the hypothalamus that controls automatic actions such as heart rate, breathing, etc.

suprachiasmatic nucleus

part of the hypothalamus that plays a key role in regulating sleep-wake cycles

amygdala

almond-shaped clump of neurons at the base of the temporal lobe that deal with emotional responses and memories

primary motor cortex

area of the brain within the frontal lobe, that controls voluntary movement

primary auditory cortex

area within the temporal lobe that processes auditory information

primary visual cortex

area within the occipital lobe that processes visual information

somatosensory cortex

area within the parietal lobe that receives information about bodily sensations

association area

on all four lobes, areas that combine sensory and motor information; coordinate interaction among different brain areas