Physiological Psychology - Chapter 4

Front 1

Experimental ablation:

Back 1

the removal or destruction of a portion of the brain of a lab animal; presumably, the functions that can no longer be performed are the ones the region previously controlled
major con = cannot isolate, because damage interconnecting neurons

Front 2

Lesion studies:

Back 2

a synonym for experimental ablation

Front 3

Function

Back 3

circuits w/in brain have specific function

Front 4

Behaviour

Back 4

circuits work together for behaviour

Front 5

RF lesions:

Back 5

Pass electrical current with stainless steel wire bare tip
Then turn on RF current. Heat kills cell in region around tip.
CON: also destroys axons passing through

Front 6

Excitoxic lesions:

Back 6

a brain lesion produced by intracerebral injection of an excitatory amino acid, e.g. kainic acid
Inserted via “cannula” tube
PRO: spares axons passing through

Front 7

Sham lesion

Back 7

placebo procedure that duplicates all the steps of producing a brain lesion except the one that actually causes brain damage

Front 8

Reversible lesions

Back 8

Local anesthetic
“muscimol” drug. Blocks action potentials
Stimulates GABA receptors, inhibiting neuron activity there

Front 9

Stereotaxic surgery

Back 9

brain surgery using a stereotaxic apparatus to position an electrode or cannula in a specified positon of the brain

Front 10

bregma

Back 10

the junction of the sagittal and coronal sutures of the skull, often used as ref. point for stereotaxic surgery

Front 11

stereotaxic atlas:

Back 11

a collection of drawings of sections of the brain of a particular animal with measurements that provide coordinates for stereotaxic surgery
*Labelled posterior/anterior to bregma

Front 12

Stereotaxic apparatus:

Back 12

a device that permits surgeon to position an electrode or cannula into specific part of the brain

Front 13

Fixative

Back 13

chemical such as formalin (re: fermaldehyde); used to prepare and preserve body tissue

Front 14

Formalin

Back 14

the aqueous solution of formaldehyde gas; the most commonly used tissue fixative
- Halts autolytic enzymes which would turn brain into mush

Front 15

Perfusion

Back 15

the process by which an animal’s blood is replaced by a fluid such as a saline solution or a fixative; in prep for histological exams

Front 16

Microtome

Back 16

Slices brain!!!
instrument to slice body tissues

Front 17

Staining

Back 17

Methylene blue: Nissl, German neurologist dye brain
Cresyl violet: fibers not stain, so can see neurons *glia & nerve

Front 18

Transmission electron microscope

Back 18

a microscope that passes a focused beam of electrons through thin slices of tissue to reveal extremely small details

Front 19

Scanning electron microscope

Back 19

a microscope that provides a 3D info about the shape of the surfaces of a small object by scanning the object with a thin beam of electrons

Front 20

Confocal Laser Scanning Microscopy:

Back 20

- A microscope that provides high-resolution images of various depths of thick tissue that contains fluorescent molecules by scanning the tissue with light from a laser beam
Possibly to deep into thick tissue
Parts of tissue stained with fluorescent dye

Front 21

Anterograde labeling method

Back 21

MOVING FORWARD
a histological method that labels the axons and terminal buttons of neurons whose cell bodies are located in a particular region

Front 22

PHA-L:

Back 22

a protein derived from kidney beans and used as an anterograde tracer; taken up by dendrites and cell bodies and carried to the ends of the axons

Front 23

Retrograde labeling method

Back 23

MOVING BACKWARD
a histological method that labels cell bodies that give rise to the terminal buttons that form synapses with cells in a particular region

Front 24

fluorogold

Back 24

a dye that serves as a retrograde label, taken up by terminal buttons and carried back to the cell bodies

Front 25

Pseudorabies

Back 25

weakened form of pig herpes virus used for retrograde transneuronal tracing, which labels a series of neurons that are interconnected synaptically

Front 26

Herpes Simplex virus:

Back 26

form of herpes virus used for anterograde transneuronal tracing, which labels a series of neurons that are interconnected synaptically
- VIRUSES PASS THRU SYNAPSES, ABLE TO LOCALIZE PROTEIN PRODUCED BY VIRUSES

Front 27

CT scan (computerized tomography

Back 27

“tomos” (cut),”graphein”, the use of a device that employs a computer to analyze data obtained by a scanning beam of Xrays to produce a 2D pictures of a slice thru the body

Front 28

Magnetic Resonance Imaging:

Back 28

a technique whereby the interior of the body can be accurately imaged; involves the interaction between radio waves and a strong magnetic field
HOW?
Hydrogen atoms align with magnet
Pass radio frequency wave thru
Atoms flip at angle to magnet & then back to original position
Released energy from radio wave
b/c diff amount of H2O – hydrogen in diff parts, diff energy
akes pictures from signal detected

Front 29

Diffusion tensor imaging

Back 29

an imaging method that uses a modified MRI scanner to reveal bundles of myelinated axons to the living human brain

Front 30

Single-unit recording:

Back 30

recording of the electrical activity of a single neuron

Front 31

Macroelectrodes:

Back 31

an electrode used to record the electrical activity of large numbers of neurons in a particular region of the brain; much larger than a microelectrode
- Unsharpened wires on head, screw attached to skull or disks on scalp
- results on polygraph

Front 32

Electroenecephalograms (EEGS):

Back 32

“writings of electricity from the head”, on scalp, an electrical brain potential recorded by placing electrodes on the scalp

Front 33

Magnetoencephalography

Back 33

a procedure that detects groups of synchronously activated neurons by means of the magnetic field induced by their electrical activity; uses an array of superconducted quantum interference devises, or SQUIDS
- cruder image than fMRI but moves faster so pick up fast moving events

Front 34

2- deoxyglucose: (2-DG)

Back 34

a sugar that enters cells along with glucose but is not metabolized
NOT METABOLIZED SUGAR!

Front 35

Autoradiography

Back 35

a procedure that locates radioactive substances in a slice of tissue; the radiation exposes a photographic emulsion or a piece of film that covers the tissue

Front 36

Fos

Back 36

protein produced by the nucleus of a neuron in response to synaptic stimulation
- LOOK FOR PROTEINS THAT CREATED FROM ACTIVATION

Front 37

FUNCTIONAL IMAGING:

Back 37

computerized method of detecting metabolic or chemical changes in a particular region of the brain

Front 38

Positron Emission Tomography:

Back 38

: a functioning imaging method that reveals the localization of a radioactive tracer in a living brain
- VERY COSTLY!

Front 39

Functional MRI:

Back 39

a functional imaging method; a modification of the MRI procedure that permits the measurement of regional metabolism in the brain, usually by detecting changes in blood oxygen level (BOLD)
- looks at brains use of blood which indicates acitvity

Front 40

Optogenetic methods:

Back 40

the use of a genetically modified virus to insert light-sensitive ion channels into the membrane of a particular neuron in the brain; can depolarize or hyperpolarize the neurons when light of the appropriate wavelength is applied

Front 41

Retinitis pigmentosa?

Back 41

Degenerative of photoreceptor cells (rods die!)

Front 42

Transcranial Magnetic Stimulation

Back 42

stimulation of the cerebral cortex by means of a magnetic field produced by passing pulses of electricity through a coil of wire placed next to the skull; interferes with the functions of the brain region that is stimulated

Front 43

Locating particular neurotransmitters?

Back 43

1. find chemicals themselves (e.g. expose to antibody for protein and then dye and examine)
2. find enzyme make protein

Front 44

Locating particular receptors?

Back 44

Two ways:
1. autoradiography: slices of brain w/radioactive ligand for receptor, rinse and use autoradiography
2. immunocytochemistry: receptors are proteins, expose to antibody, look at microscope with wavelengths

Front 45

Microdialysis

Back 45

a procedure for analyzing chemicals present in the interstitial fluid through a small piece of tubing made of a semipermeable membrane that is implanted in the brain
- e.g. look at levels of heroin and relative dopamine increases

Front 46

Genome

Back 46

complete set of genes that composes the DNA of certain species
- human = roughly 25,000

Front 47

Allele

Back 47

nature of a particular sequence of base pairs of DNA that constitutes a gene; for examples, the gene that code for blue or brown iris pigment are different alleles of a particular gene

Front 48

Targeted mutations:

Back 48

a mutated gene (“knockout gene”) produced in the laboratory and inserted into chromosomes of mice; fails to produce functional protein

Front 49

Antisense oligonucleotides

Back 49

modified strands of RNA and DNA that binds with a specific molecule of mRNA and prevents it from producing its protein