Psych 3313 Chapter 1

Optogenetics

Activating or inactivating a light sensitive protein using a light. When the light is activated, the proteins are activated and thus a behavior is activated. When the light is off, the behavior is no longer expressed.

Cons of Phrenology

Bad because there was no science and not even correct. It was used to justify sexism, racism, slavery. Ex. A stretched skull would mean a that person is evil when that would not be true.

Santiago Ramon y Cajal

Believed that the nervous system composed of array of separate independent cells. However, he couldn't see that, proposed and thought of that. He was correct.

What are some modern day ethical issues?

How to have data from internet and use it ethically. People usually need to have consent for internet STEM cells. People have relied on them to find out basic information on the brain. Some STEM cells are derived from fetal embryos which is unethical.

Trepanation

Prehistoric brain surgery where people would drill holes into people's skulls to release demons or bad energy from the brain.

Tract Tracing

a method of figuring out which brain regions will connect with each other and communicate. Take a fluorescent tracer or dye and inject into brain regions. Some dyes will move backwards "retrograde" (where a brain is receiving a message from) while others may go forwards "anterograde" (where a brain message is going to)

Deception if Necessary

Sometimes is necessary in order to see how people behave how humans actually behave. Needs to be reveiewd by a review board to determine if its reasonable.

Experiment

characterized by manipulating variables, random assignment, control of extraneous or confounding variables, manipulation of a condition, measurement of changes from the manipulation

Genetically modified animals (knock out genes)

adding or removing proteins which will control the gene expression. Other methods include the genes have a switch where they can be turned off during certain times of their life. Good because manipulation allows causality of gene affects.

Control Group

does not receive the manipulation

Neuron Doctrine

established by Cajal and not proven until the development of electron microscopy in 1950s. (doctrine was that neurons were in separate independent network

Golgi Stain

single cells, darkly stains full single neuron. Randomly stains about 5% of neurons

Hypothesis

testable (yes/no) prediction that is used to guide further research

Independent Variable

manipulation of a condition

Dependent Variable

measurement of changes from the manipulation

Informed Consent

need to tell people what they are going to do for the experiment

Camillo Golgi

nervous system consists of vast interconnected web of fibers. Developed a popular technic called Golgi staining by staining the Golgi cells with black dye.

Ratbot Experiment

neurologists implanted stimulators inside a rat's brain and could guide them to where they should go by changing direction. Application for humans with spinal cord injury.

Debriefing

the experiment tells you the hypothesis, question, what they were testing and why you participated in it

Neuroscience

the scientific study of the brain and nervous system in health and in disease. Draws from psychology, biology, physiology, genetics, biochemistry, neuroscience

Immunocytochemistry

uses antibodies attached to a dye to identify the presence of proteins including receptors, neurotransmitters, hormones, or enzymes. Good because you can look for single types of neurons compared to Golgi where its all types of neurons.

Computerized Tomography

uses multiple x rays to construct a 3D image. Can determine any major changes in the brain, bleeding, tumor, injuries. Not used a lot due to X-Ray exposure Temporal Resolution: Very fast Spatial Resolution: Very good

Brain stimulation

"transcranial magnetic stimulation" artificially stimulating the areas of the brain with electricity or magnetism and watching for resulting behavior. Can be applied during neural surgery. The most stimulating research has been conducted with laboratory animals.

Galen

(130-200 AD) Conducted animal dissections and study of gladiator injuries to understand anatomy. Proposed idea that fluid chambers play important role in nervous system to control body that ultimately connect to the brain.

Galvani

(1780) disproved the fluidic reflex model which showed that the nervous system was operated by electrical transmission

Hippocrates

(460-379 BC) First to suggest that the brain was the source of intelligence

Institutional Oversight

(Institutional Review Board) IRB reviews your experiment and all aspects so that they can determine if the experiment is fit to be conducted. Everything must be approved

Descartes

- Perpetuated fluid driven model of how the body works. - Pineal gland was the seat of the soul. - Dualism: the idea that the mind, and body are separate entities.

2 types of imaging technologies in animals

2 photon microscopy and in vitro brain slices: time lapse imaging

Event Related Potential

A spike or increase in electrical change in a specific brain region in response to an environmental stimulus. Commonly used for perception, audition, and cognitive processes.

Phineas Gage

Accidental experiment in 1848 that revealed that parts of the brain were dedicated to function of the brain. After the accident, his personality change which is correct because the frontal lobe is part of personality and judgement.

Why are some animals used in experiments instead of humans?

Animals are used because it is more ethical and a lot of subjects can be gathered quickly and cheaply. Large biomedical experiments are done on mice. Animals have a controlled environment, very easy to get rid of any confounds. Animals have the homogenous background, same diet, same age, same genes. Animals have a briefer development, can scale the stages of development quicker than humans Some experiments are not ethically be completed in people (brain injuries, spinal injuries)

Animal Ethical Requirements

Animals can only be used if the research is necessary, crucial to helping humans or animals Need to provide basic care and housing for animals Provide minimal pain and distress as possible

How does an fMRI detect neural activity

Blood that has hemoglobin has a different magnetic property with ones without it, that's how they detect the different activity levels. It sends BOLD (blood-oxygen-level-dependent signal)

Pros of Phrenology

Brought the idea that there were different sections in the brain dedicated to certain functions

Therapy and Brain manipulation

Brain stimulation can also be used in therapy. Some people with Parkinson's disease has surgery where certain brain areas can be stimulated to activate neural activity.

Ramon y Cajal vs Golgi

Cajal thought independent separate webs but Golgi thought it was one vast connected network

Pro of an Experiment

Can say cause and effect relationship because all of the other variables are controlled so you can infer causality

Cons of Correlational Study

Cannot say that there is a cause and effect relationships

Human Participant Guidelines

Coercion (persuading) of research participants is unacceptable. Cannot pay or benefit participants (can't give a lot of money). Participants must be informed that they can leave without penalty. Can walk out anytime. Participants information must be anonymous and protected. Participants must receive contact information in case they have questions

2 photon microscopy

Commonly used in animals. Can detect how many neurons were being fired during a given task.

Phrenology

Created by Franz Joseph Gall and Johann Casper Spurzheim. Suggested that the structure of people's skulls including their bumps and shape would correspond to the function of the brain. Each section of the brain would be dedicated to a part of their identity.

Reflex of Descartes

Descartes thought that a fluid would signal to the brain to react to a stimulus. Basis model of nervous system

Two Inter-Related Questions in Neurobiology

Determining the relationship of the structure of neural anatomy and the function. (How is it built? - How does it work?)

Current Focus in Neuroscience

Functional brain circuits and the connectome.

What is one bad part of brain screenings?

It is an indirect measurement because it is not testing electrical neural activity.

Magnetic Resonance Imaging

MRI, magnetic field and radio waves used to produce high-resolution structural images of the brain. The water molecules are detected to determine the structure of the brain. Only give pictures of the brain. Temporal Resolution: Slow Spatial Resolution: Not good

Positron Emission Tomography

PET, Injection of a radioactive substance into the bloodstream. The brain uses the radioactive sugar as fuel and can detect which brain regions will use up the sugar as fuel, especially during a given activity. (activity during task - activity at baseline = difference image) Temporal Resolution: Very slow Spatial Resolution: very good

Electroencephalography (EEG)

Scalp electrodes placed on head that provide information about the electrical impulses of large populations of neurons. Commonly used to study sleep and diagnose seizures. Very common because it is a lot cheaper than other methods. Temporal Resolution: Very fast Spatial Resolution: Not good

Imaging Structure

Structural technique that assesses the shape and size of brain regions in living patients. Uses Computerized Tomography (CT), Magnetic Resonance Imaging (MRI), Tract Tracing, Histology, Immunocytochemistry, Golgi Stain

20th Century Localization View

The view that only certain centers and specific locations were dedicated to function of the brain. In reality, functions are localized in the brain but also distributed. Different brain regions collaborate to work together to produce a function.

What are the methods that records the brain?

These are considered to be assessing function, but consist of Magnetoencephaolgraphy, electroencephalography, and neurophysiology

Transcranial Magnetic Stimulation

applies strong and quickly changing magnetic fields to surface of skull that can interrupt brain function. Used to determine how the inactivate brain regions affect cognition or behavior, sometimes used to study depression or schizophrenia

Magnetoencephalography

brains magnetic output is assessed. The skull is transparent to magnetism, not electricity, making MEG less distorted than EEG. Localization of activity is possible. However, it is very expensive, so it is less popular. Temporal Resolution: Very Fast Spatial Resolution: Good

Downside of an experiment

can't control all variables. Best to integrate experiments and correlational studies. Also may lack generalizability from lab to real world (external validity)

Nissal Stain

cell bodies of neurons, more packed cells will take up more dye and look darker.

Twin Studies

compare variable of interest between identical (monozygotic) and fraternal (dizygotic) twins. Contribution of heredity is stated as concordance rate (the proportion of which attributes are genetically similar amongst twins).

Imaging Function

detect which brain regions are more or less active during an activity. Uses fMRI, PET, Magnetoencephaolgraphy, 2 photon microscopy, imaging brain cells, neurophysiology, electroencephalography

Neurophysiology

directly measures electrical activity in the brain by implanting an electrode within a neuron or in the brain. Very good spatial and temporal resolutions. This correlates with cognitive and behavioral events. Very ideal because they are good for experiments.

Functional Magnetic Resonance Imaging

fMRI, the molecules in the brain will let off magnetic charges. Examines the changes in the blood flow and blood oxygenation in the brain which is correlated to neural activity. During a task, parts will show that there is stronger blood flow to parts of the brain that are especially active. Usually measured at a baseline and then tested for the experiment. Poor temporal resolution, good spatial resolution

In vitro brain slices

fluorescent die is used to determine how the neurons and proteins activate

Neuropharmacology

in animals, drug infusion can be localized through the use of guide cannula. Then examining the cognitive and behavioral affects.

Minimize pain

in order to conduct experiments with humans and in animals, people must minimize pain, discomfort and risk.

Theory

integrates and interprets many observations to explain a phenomenon. Sometimes the theory may not always be right, might need to be adjusted or the experiment must be redesigned. Theories are sometimes not always accepted because there is a chance that information will always change

Monism

modern neuroscience belief in which mind, personality, emotion and all other aspects are directly from the brain.

Biological Psychology

now called Behavioral Neuroscience. The branch of psychology that studies the biological foundation of behavior, emotions, and mental processes

Experimental Group

receives the manipulation

Lesions

removing a small brain region that have been injured. Examine how the removal of that brain region affects cognition or behavior. Can sometimes temporarily affect the brain regions by heating and cooling

Correlational Study

systematic research design that does not manipulate but observes whether two variables are connected. Can be negative, positive, or zero (zero meaning no correlation)

Genome Wide Association Studies

taking DNA upon thousands of people that have a condition and sequence their genomes to find the genetic similarities that are responsible for that condition. However, this is still correlational and does not imply causation.

Microdialysis

taking out fluid in the brain to detect certain levels of substances (neurotransmitters)

Temporal Resolution

the ability to detect changes in neural activity.

Spatial Resolution

the ability to locate neural activity

Histology

used for microscopic brain tissue that is not alive. 1) fixed by freezing or formaldehyde so its stable 2) slicing the tissue very thing by vibrating a microtome or cryostat 3) mount the sections of the brain tissue on microscope slides 4) stain the sections to highlight structures of interest (commonly use fluorescent signals) 5) viewed with a microscope (different microscopes for different examinations)