PSC 135 - Cognitive Neuroscience Exam #1

cells of the nervous system

neurons and glial cells

neurons

process and communicate information

glial cells

protect and nourish neurons, supportive role

types of glial cells

astrocytes, oligodendrocytes, microglia, schwann cells

dendrites (send or receive)

receive

axon terminals (send or receive)

send

purkinje cells

most intricate dendritic tree in all animal species, exact function unknonw

myelin

insulates axons and accelerates impulse propagation, protects signals from getting lost

message traveling order

dendrites —> cell body —> axon terminal

typical neuronal signaling

electrical = within a neuron

chemical = between neurons

resting potential = neuron is inactive

k+ inside the cell, Na+ outside the cell

electrochemical gradient of a neuron

inside = -

outside = +

disruption of blood flow in the brain

stroke, neuron (cell) death

sodium/potassium pumps

expend ATP to move ions against the gradient

active transport

non gated sodium/potassium channels

always open

voltage gated ion channels

electrical

ligand gated ion channels

chemical

ions that cause depolarization during influx

inside of cell becomes more positive = Na+ = excitatory

muscle contractions = Ca2+

ions that cause hyperpolarization during influx

K+ = membrane potential is hyperpolarized

Cl- = inside of cell becomes more negative = inhibited

gated channels

transmembrane proteins

ESPS

voltage starts at -70 (resting potential) and peaks at 0 — excitatory

happens when ligand-gated sodium channels are opened

ISPS

voltage starts at -70 (resting potential) and peaks at low negative — inhibitory

happens when ligand-gated chlorine channels are opened

length constant

distance over which membrane potential has dropped to 37% of initial value

time constant

time over which membrane potential has dropped to 37% of initial value

AP spike triggered at axon hillock

depolarization, voltage gated sodium channels are now open

sodium activated channels cannot start another spike for:

1-2 ms (refractory period)

Golgi

Synctyium

Ramon y Cajal

Neuron Doctrine

Neuron Doctrine

neurons = building blocks for the brain

transmit electrical impulses from dendrites to axon terminals

selective permeability of pumps and ion channels

responsible for membrane potential

Ohm’s Law

I = V/R

dendrites

collect chemical signals from other neurons and transform them into electrical

cell body

integrates incoming signals; can generate a digital electrical impulse in response

axon

transmits electrical signal to its terminals, where it is transformed into a chemical signal and transmitted to postsynaptic cells

all or none law

spike does not vary in amplitude, varies in the amount of spikes that occur and the rate at which they are occuring (faster = more spikes)

order of speed of signaling

AP > ESPS > IPSP > other

ESPS is caused by

glutamate

ISPS is caused by

GABA

neuromodulators

cause slower electrical/nonelectrical effects

Neuromodulatory systems

1. dopamine

2. norepinephrine

3. histamine

4. serotonin

Dopamine function

reward, addiction, motor regulation

Histamine

wakefulness, circadian rythyms

Norepinephrine

arousal, alterness, stress

Serotonin

mood, emotional stability, sleep/wake cycles

ESPS and ISPS summate at:

the cell body

Depolarization

AP spike is triggered at the axon hillock

synaptic addition

sum of ESPS

synaptic subtraction

sum of ISPS

synaptic multiplication

increase in Rm (resistance)

synaptic division

decrease in Rm (resistance)

Boolean AND logic — coincidence detection

NMDA-type glutamate receptor is only activated when there is some membrane depolarization (to drive magnesium out) AND glutamate binds to the receptor

short term synaptic depression

leads to high pass filtering (only allowing high frequencies to pass)

short term synaptic potentiation

leads to low pass filtering (only allowing low frequencies to pass)

electrical transmission BETWEEN neurons

even closer than chemical, not as abundant, faster but not as versatile as chemical

microcircuits

connectivity between nerves

neural networks

PNS, CNS, ANS

PNS

autonomic and somatic

CNS

brain and spinal cord

somatic nervous system

sensory nerves from body leading to brain

moto nerves from brain leading to muscles

autonomic nervous system

sympathetic nervous system and parasympathetic nervous system

sympathetic NS

fight or flight

parasympathetic NS

rest and digest

Rostral

left (anterior)

Caudal

right (posterior)

Ventral

bottom (inferior)

Dorsal

top (superior)

Lateral view

from the side of the brain, you can see all the lobes from the outside

medial view

middle of the brain (cut open laterally down the middle), you can see all the lobes from the inside

what is this called

sagittal section

what is this called

axial/transverse/horizontal

what is this called

coronal

Ipsilateral

on the same side of the body

contralateral

on opposite sides on the body

unilateral

involving one side of the body

bilateral

involving both sides of the body

gray matter (default)

cell bodies and dendrites

white matter

myelin and axons

brain stem

medulla, pons, cerebellum, midbrain

cerebellum

purkinje neurons, deep cerebellar nuclei, most neurons contained

midbrain

connection between forebrain and hindbrain, vision and eye movement, hearing, motor control, dopamine, pain suppression, arousal/alterness

Diencephalon (forebrain)

thalamus and hypothalamus

thalamus

collection of sensory, motor, and associative (pulvinar) nuclei, except for smell all sensory signals will go to the cerebrum through this part of the brain

hypothalamus

controls endocrine and physiological responses such as fight or flight, hunger, satiation, blood pressure (not really cognition)

Cerebrum (Telencephalon)

limbic system

limbic system parts

hypothalamus, amygdala, hippocampus, thalamus, cingulate gyrus, basal ganglia

hippocampus

Turns short-term memories into long-term memories and helps with spatial navigation

amygdala

Manages emotions like fear, anger, and anxiety, and helps recognize threats

basal ganglia

regulates (not initiates) motor movements

sulci

The shallow grooves, indentations, or furrows that separate the gyri. (Very deep sulci are often called fissures)

gyri

The raised ridges, bumps, or peaks on the surface of the cerebral cortex

frontal lobe

manages higher-level thinking, voluntary movement, language production, and emotional control

handles decision-making, problem-solving, planning, organization, reasoning, and working memory

The primary motor cortex controls intentional physical actions, such as walking, reaching, and moving your hands or face

Broca’s area coordinates the mouth and throat muscles needed to produce spoken language

It regulates impulses, self-control, empathy, and your understanding of social norms

Dopamine pathways in this region drive goal-directed behavior and feelings of reward

parietal lobe

It houses the primary somatosensory cortex (in the postcentral gyrus), which receives and interprets tactile signals including touch, pressure, temperature, pain, and vibration

It tracks the position, movement, and orientation of body parts (such as knowing where your hands or feet are without looking)

It constructs a spatial coordinate system to help you navigate your surroundings, judge distances, and avoid bumping into objects.

It combines inputs from vision, hearing, and touch to create a unified perception of the world.

occipital lobe

Receives and decodes raw visual signals (light, shapes, edges, and motion) sent from the retinas via the optic nerves and thalamus

Analyzes color properties, distance, size, and binocular depth perception

Connects to the temporal lobe to help identify and recognize objects, text, and faces.

Connects to the parietal lobe to track movement and guide spatial awareness and physical actions (like reaching or navigating)

handles initial feature extraction and conscious awareness of visual input.

Interprets higher-order visual details like complex patterns, color constancy, and motion tracking

Temporal lobe

The primary auditory cortex receives sound signals from the ears, helping you interpret pitch, volume, and rhythm

Wernicke’s area helps you comprehend spoken and written language

the hippocampus inside this lobe converts short-term experiences into long-term declarative and semantic memories

The amygdala processes emotional reactions, social cues, and threat responses

identify complex visual stimuli like everyday items and human faces

advantages of the human brain

1. more neurons in the cerebral cortex than any other species

2. pack more neurons per volume than other mammals

single dissociation

brain area X is needed for reading numbers; not needed for reading letters

double dissociation

brain area X is needed for reading numbers; not for reading letters; brain area Y is needed for reading letters; but not for reading numbers

deep brain stimulation

surgical implants of a microelectrode directly in the brain, sends signal and is beneficial to patients with certain cognitive disorders

transcranial magnetic stimulation

low level currents that result in action potentials under anodes (from scalp), manipulates brain activity, used to briefly stop cognitive processing, can excite or inhibit neurons, greater impact on surface cortical areas

transcranial focused ultrasound

low intensity ultrasound waves, enhances voltage-gated sodium and calcium channel activity, finer spacial resolution