PSYC 311 Exam 1

Frontal or Coronal Plane

Frontal or Coronal Plane

a cut dividing anterior and posterior portions

Sagittal Plane

cut running anterior to posterior dividing left and right sections

Horizontal or Transverse Plane

Anatomical Directions

IACUC

Institutional Animal Care and Use Committee

Ensures compliance with humane care of animals in research. Must review research facilities’ once every 6 months

Positive findings bias

studies in which some independent variable is
shown to have a significant effect on the dependent variable tend to be more
readily published and appear in higher-impact journals.

Variables

any characteristics that can take on different values, such as weight, age, temperature, or maybe...yawning times.

reliability vs validity

reliability- consistent results

validity- how well the test measures

internal validity vs external validity

internal - the extent to which any effects on the dependent variable can be attributed to the independent variable (only the study)

external - the extent to which the results of a study can be applied outside of that specific context (bigger picture)

Within subject design vs between subject design

within - the same participants tests all conditions corresponding to a variable ; repeated measures

between - different participants are assigned different conditions corresponding to a variable ; independent measures

confound

an independent variable that is conceptually distinct but empirically inseparable from one or more other independent variables

Ex. In a study on the effect of sleep on memory, if the amount of caffeine consumed by participants is not controlled, caffeine becomes a confound.

caveat

warning of specific stipulations, conditions, or limitations.
Ex. If a study on memory improvement was conducted exclusively on male rodent
Caveats plague science: only recently did the NIH require that both sexes are tested.

Categorical variables vs Quantitative variables

categorical - names or labels (eye color, gender, breed, etc)

quantitative - numeric

null hypothesis vs alternative hypothesis

null - a test always predicts no effect or no relationship between variables. H0- male yawns = female yawns

alternative - your research prediction of an effect or relationship. Ha- male yawns > female yawns

P value

The probability that, given the null hypothesis
is true, a result could occur.

if the p-value is below your threshold of significance (typically p < 0.05), then you can reject the null hypothesis

data cleaning

is the process of fixing or
removing incorrect, incomplete data
within a dataset

T test vs ANOVA

T test - Compares 2 means; Determines significant difference of means

ANOVA - Analysis of variance– how do 2 or more
groups vary? Determines significant difference in variance from the mean

coronal/frontal section

sagittal/medial section

horizontal/transverse

CNS

Brain and spinal cord

PNS

Nerves and sensory organs, ganglia
- Nerves: bundles of axons within the PNS
- Sensory organs: eyes, ears, nose, tongue, skin
- Ganglia: bundles of neuronal bodies within the
PNS

Frontal lobe

CNS ; Working memory
• Executive functions (focus, planning,
impulse control, etc.)
• Motor cortex

Parietal Lobe

Somatosensory cortex (touch, pain, body
position etc.)

Temporal Lobe

Language production and perception
• Auditory cortex

Occipital Lobe

Visual cortex

Cerebellum

Incredibly densely packed with neurons
Functions : Balance and muscle memory

Gyri and Sulci

Gyrencephalic vs Lissencephalic

Gyrencephalic: having cerebral hemispheres marked by gyri and sluci (primates, sheep, large mammals) These folds allow for greater surface area

Lissencephalic: smooth brain (rodents, small animals, less time to produce)

Lateral Sulcus (Sylvian Fissure)

• Separates the temporal lobe from the frontal and parietal lobes
• Superior temporal gyrus (sound reception and processing)

Central Sulcus

Separates the frontal lobe from
the parietal lobe
• Precentral gyrus (motor cortex)
• Postcentral gyrus
(somatosensory cortex)

Ventricles

Four interconnected channels filled
with cerebrospinal fluid (CSF) to protect the brain, clear waste, and provide nutrients and ions
used in neural transmission.
• Ventricles I and II: lateral ventricles
• Ventricle III: surrounds the thalamus
• Ventricle IV: between the cerebellum and
brainstem

Grey vs White Matter

Grey Matter: Somas (cell bodies) and Dendrites
White Matter: Myelinated axons

Why use animals?

- It enables ethical exploration of invasive experiments that cannot be performed on humans.
- Good for testing neurological diseases, like Alzheimer’s and Parkinson’s.
- Rodents and other animals share significant genetic and biological similarities with humans,

95% of animal research is rats and mice

Examples of animal studies

Pavlov dog, Non-human primates, Throndike’s cat

Why rodents?

• Social
• Curious and smart
• Short (but not too short) lifespans
• Can be modified through breeding or
genetic editing to possess a number of
traits/phenotypes
• Easy to house and handle
• Tools for observing the rodent brain are
readily available.
• Extensively studied. Tons of data
available!

Rodent Ethology

Social Structures: individuals form complex social hierarchies and engage in grooming and bonding behaviors.
Nocturnal Behavior: Rodents are primarily
nocturnal, showing increased activity during the
night and resting during the day.
Burrowing: Rodents create elaborate
underground tunnel systems that serve as nests,
foraging areas, and protection from predators.
Foraging Behavior: Rats exhibit scavenging
behavior, often exploring urban environments to
find and exploit diverse food sources.

rat v mice

Rats - more complex behavior, more suitable for cognitive tasks and social interactions ; Tend to have superior spatial memory and learning
capabilities, more suitable for task experiments ; Exhibit more pronounced social structures and interactions, which are useful for studying social behavior and hierarchy.

Mice - used for more straightforward behavioral assays ; often used in genetic studies related to learning and memory due to their well characterized genome ; Display social behaviors but are less complex compared to rats

Rotarod test

The Rotarod is a device used in animal research to assess motor coordination and balance by
measuring how long a rodent can stay on a rotating rod

Hot plate test

Tests Sensory ability - The hot plate test is used in rodent studies to measure pain sensitivity and analgesic effects by assessing the time it takes for a rodent to respond to a heated surface.
- At what point does the rat respond as if the hot plate is painful?
• Can test analgesic drugs.
• Ethics are important here, we want to see mild
discomfort in the rat, not an extreme pain response

Open field test

Tests navigation - An open space that allows rodents to freely explore

Elevated plus maze

Tests anxiety - uses natural rat fears

Forced swim test

Tests depression - used to evaluate
depressive-like behavior in rodents by measuring
how long they persist in attempting to escape from a confined, inescapable water tank.

Tube test

used to assess social dominance and
aggressive behavior in rodents by observing their interactions when confined in a narrow tube.
• The test observes which animal is able to push the other out of the tube, indicating dominance.

Visual burrow system

Studies group behaviors - open arena and a series of tunnels and burrows

Patch-leaving

Studies foraging to assess decision making by measuring how rodents leave one patch of food to explore and exploit new patches in search of additional rewards

Operant conditioning

The operant chamber is a controlled environment used to study animal behavior by
measuring responses to stimuli, such as pressing levers or pecking keys, to obtain
rewards or avoid punishments ex. push lever to get food or punishment to decrease behavior

radial arm maze

Working and Reference Memory
• Remember which arms they’ve
already collected rewards from
on that day. (working)
• Remember which arms contain
rewards from previous
experiences on the maze (reference)

barnes maze

Learn and remember the location of a
target zone using distal cues.
• Intrinsic inclination of the rodents to escape
from an aversive environment

morris water maze

Learn and remember the location of a hidden
platform using distal cues.
• Dislike of water

Silico vs Vitro vs Vivo

silico - experiments using computer simulations or models ; best for brain function models, study neurodisorders

In Vitro - Experiment outside of a living organism. Ex. Patch clamp - tool that can measure electrical currents flowing through ion channels in cells

In Vivo - Experiment in a whole, living organism. Ex. lesion studies (not done on humans unless patient HM who had temporal lobe surgery to cure epilepsy but ended up damaging ability to form new memories)

Invasive stereotaxic surgery

A stereotaxic device uses three coordinates to pin the location of brain sections where probes can be placed to deliver drugs, monitor neural activity, monitor neurotransmitter levels, induce lesions

Lesion techniques

Chemical injection - Kainic acid is injected to kill cells in hippocampus

Radiofrequency - wire electrodes passes radiofrequency to heat the tissue and kill axons and somas

temporary control techniques

Chemical inactivation: using chemicals to temporarily block or inhibit the activity of neurotransmitter receptors, allowing research of the effects of reduced neural activity on behavior and neural processes

chemogenetics: uses viruses to alter gene expression, to control the activity of specific neurons in order to investigate the relationship between neural activity and behavior

optogenetics: uses light to control genetically modified neurons, allowing researchers to manipulate neural activity to study behavior and brain function

Single unit electrophysiology

Using a microelectrode to record electrical activity in a neuron, which can detect the rate and patterns of firing neurons to tell us about neural functions (direct, invasive, high spatial and temporal resolution)

calcium imaging

measures calcium ion status in brain cells (high spatial and temporal resolution, invasive, indirect signal)

CT

imaging technique that uses xrays and computer processing to create images, showing internal structures and abnormalities

MRI

powerful magnets produce a magnetic field to force protons in the body to produce 3d images

Histology

study of microscopic structure of tissues using cutting and staining techniques

Nissl Staining

Can differentiate DNA and RNA (negatively charged molecules) by staining the soma (cell body) used for counting cell number and trace a structure for volume

Golgi Staining

used to examine dendritic branding and number of spines

Immuno Staining

immunohistochemistry (IHC) selects for specific proteins within the cells of a tissue section

Uses antibodies to target specific proteins

Used to count proteins, study their morphology, and pinpoint location

Microscopy

Allows us to view cells

c-FOS

gene expression; action potential triggers translation of cFOS protein to indirectly measure recent neural activity

tract tracing

labels somas and axons tracts

connectomics- understanding the architecture of the nervous system and the patterns of synaptic connectivity that are thought to underlie functional properties of neural circuits

anterograde tracing - traces from origin to termination (soma to terminal)

retrograde tracing - traces from termination to origin

transgenic

animals who have been genetically altered

knock out models

mutate a gene to the point that it is non-functional

knock in models

adding in genes or variants of genes

microdialysis

cells release neurotransmitter in during an action potential

probe placed into region of interest and it samples and collects neurotransmitters and other substances

grey matter

made up of cell bodies

white matter

made up of axons, usually a tract or pathway

sulcus/fissure

grooves or crevices in the cerebral cortex (brain’s most outer layer)

gyrus vs sulcus

gyrus - ridges of the cerebral cortex

sulcus - grooves or crevices

tract

a group of axon fibers connecting different areas of the brain

nerve

same as a tract but outside the central nervous system

contralateral vs ipsilateral

contralateral - opposite side

ipsilateral - same side

dorsal view

dorsal = back

ventral view

belly or abdomen

lateral vs medial

lateral - away from the midline

medial - toward the midline

dura mater

grayish membrane that is the outer most layer of the meninges, membranes that keep spinal fluid

cruciate/central sulcus

(O) or ansate sulcus; divides frontal lobe and parietal lobe

longitudinal fissure

(O) This is the major fissure that runs along the midline of the brain, separating the brain into two hemispheres

sylvian sulcus

(O) This is the sulcus running vertically towards the cruciate/central sulcus.
This forms the frontal boundary for the temporal lobe and is shown in the lateral view of the brain

superior frontal gyrus

(O) Also known as the precoronal gyrus, this is the question mark shaped
gyrus in the frontal lobe that lies anterior to the cruciate/central sulcus.
This is the primary motor cortex for the sheep

rhinal sulcus

(O) The well-defined sulcus easily seen from the lateral or ventral view of
the brain. This sulcus forms the superior boundary for the pyriform lobe

frontal lobe

(O) this is the lobe lying anterior to the cruciate/central sulcus. where motor cortex is located and is also associated with complex cognitive functions and personality

temporal lobe

(O) contains auditory cortex and is used for higher level visual processing as well as language. most easily seen in lateral view

occipital lobe

(O) most posterior; visual cortex is here

parietal lobe

(O) lobe responsible for processing sensory information and contains somatosensory cortex.

pyriform lobe

(O) contains the entorhinal cortex and parahippocampal gyrus. involved in olfactory perception (smell)

Visual cortex

(G) in occipital lobe, the most posterior portion. complex visual processing

motor cortex

(G) bounded by the cruciate sulcus at the posterior border, the motor cortex is within the precoronal gyrus or superior frontal gyrus

somatosensory cortex

(G) region of the cortext where incoming somatosensory info is processed. It is located in the gyrus posterior to the cruciate sulcus

auditory cortex

(G) bounded at the front by the sylvian sulcus; part of the temporal lobe. home of auditory processing

entorhinal cortex

(G) posterior part of pyriform lobe, immediately inferior to the rhinal fissure. hippocampus is located just below the entorhinal cortex

optic nerve

(W) primary projection axons leaving the eye

optic tract

(W) after the optic chiasm. these are white matter axons projecting to the lateral geniculate nucleus

optic chiasm

(W) intersection of the optic nerve from each eye. The incoming axons decussate here, and project out as the optic tracts

olfactory bulb

(O) primary sensory organ for olfaction. Receives inputs from the nasal cavity and send information to the pyriform lobe for further processing

lateral olfactory tract

(W) The band of axons that connect the olfactory bulb with the pyriform
lobe. This is the main band of axons that carry olfactory information into
the brain to be processed.