CogSci 180 Midterm - Brain Basics

neuroanatomical orientations

anterior (front)
posterior (back)
dorsal (top of head or back)
ventral (bottom of skull or front of body)
lateral (toward side of body, away from middle)
medial (middle of body, away from side)

coronal or frontal section (parallel to forehead)
sagittal or lateral section (perpendicular to ground)
transverse or axial section (parallel to ground)

3 divisions of human brain

forebrain - neocortex (rational)
midbrain - limbic brain (emotional)
hindbrain - reptilian brain (instinctual)

cerebral cortex

best distinguishes us from other animals
outermost layer of grey matter (3mm thick)
26 billion neurons
sulci+gyri increase surface area
consists mainly of glia and cell bodies

includes neocortex (lobes) and limbic cortex

lobes of the brain

frontal (speaking, muscle movement, planning, judgement, emotional control)
- primary motor cortex (voluntary movements)
- prefrontal cortex (plans/judgements)

parietal (body awareness)
- primary somatosensory cortex (body surface mapped onto brain surface)

occipital
- primary visual cortex (receives visual input from opposite visual field)

temporal
- primary auditory cortex (auditory information)
- temporal parietal junction (stim causes out of body exp)
- insula

prefrontal cortex divisions

dorsolateral prefrontal cortex:
working mem, cog flexibility, problem solving, inhibition of rumination/worry

ventromedial prefrontal cortex:
theory of mind, self-perception, risk/fear processing, behavioral ctrl, decision making
includes - rostral ACC, mPFC, subgenual cingulate cortex, orbitofrontal ctx

lateralization of functions

corpus callosum connects

Left (projects to right side of body):
- analysis of info
- recognition of serial events
- language
- math computation
- logical and linear

Right (projects to left side of body)
- synthesis of info
- pattern recognition (holistic)
- identification of emotional expression
- non verbal and holistic

limbic system

assoc w emotions and memory
amygdala
hippocampus

amygdala

linked to emotion, fear/aggression
(conservatives said to have larger)

hippocampus

important in memory
anterior hippo, closest to amygdala, involved in regulating behavioral inhibition (PTSD = maybe abnormal anterior hippo activity)

anterior cingulate cortex

collar around front part of corpus callosum
integrates cognitive and affective info
processing of conflicting info
selective attention
pain perception
impulse control

insular cortex

deep within lateral sulcus
functions for body awareness, sense of self, emotion exp, empathy/compassion, addiction

basal ganglia

upper part - caudate nucleus, putamen, globus pallidus for action selection, motor seq, motor inhibition

lower part - NAc for reward learning

nucleus accumbens

lower part of basal ganglia
reward center
VTA/SNc release DA here

brain stem

automatic survival functions (sleep, arousal, heart rate, breathing, blood pressure)

cerebellum

coordinate voluntary movement and balance
plays role in higher learning

network neuroscience

functional connectivity
research can be done when ppl aren't doing anything at all

default mode network

brain areas active when participant is in resting state, not focused on particular task
can also be active in goal-oriented tasks like self-referencing, recognition of emotions, ruminating about past, worrying about future

posterior cingulate ctx and precuneus, mFC, temporopatietal junction

AD -> deteriorating connectivity of DMN

meditators show reduced DMN activity

structure of neuron

soma
dendrite
axon
terminal button
neurotransmitter
synapse

mechanisms of neural growth

neurogenesis (hippo, olfactory bulb, amygdala)
development of new synapses
dendritic branching/arborization

neuroplasticity

brain can change in response to both behavioral activity and thoughts alone

psych disorders can inc/dec activity in specific brain circuits > plasticity leads to disorder more