Class # 8: Ethics&Meth., p. 1 ETHICS & REGULATION of RESEARCH Most everyone agrees that research is...

Class # 8: Ethics&Meth., p. 1

ETHICS & REGULATION of RESEARCH

• Most everyone agrees that research is needed if we want to improve our understanding of nervous system function.

• However, as discussed in your book (Module 1.3), ethical issues about how (and sometimes whether) we should do the research have generated considerable and often heated debate. The most vehement of the debates usually concern the use of non-human animals as subjects.

• What is not well known is that, due in part to these ethical concerns, all research in the USA and most other countries, whether using humans or non-human animals, is under vigorous regulation. The The most important of these regulations is that at all most important of these regulations is that at all times the welfare of the subjectstimes the welfare of the subjects -- -- whether humans whether humans or non-human animals or non-human animals -- -- must be respected. must be respected.

• Information about research with humans can be found on FSU’s website: --See: http://www.research.fsu.edu/humansubjects/index.html.

• During the first part of today’s lecture, we will discuss the rigorous regulations associated with research using non-human animals. --See: http://www.apa.org/science/anguide.html

THE USE OF NON-HUMAN ANIMALS IN RESEARCH


A. The welfare of animals must be respected: CONSIDERED OF OVERARCHING IMPORTANCE STRICTLY REGULATED & ENFORCED -locally by FSU’s ACUC (Animal Care & Use Committee) -nationally by the USDA; -internationally by funding bodies, professional societies, & research journals

B. Today (with examples), we will consider some of the regulations and enforcement procedures.

3.

1.

2.

Part 2: METHODS OF RESEARCH IN NEUROSCIENCE

1. All methods have conceptual limitations. The the most successful way to answer a research question therefore, usually involves using a combination of different methods.

2. There are two major types of methods, each with different subcategories: A. Anatomical: These methods ask.

“What does it look like?”“What does it look like?”

B. Functional: These methods ask, ““What does it do?” “How does it work?”What does it do?” “How does it work?”


ANATOMICAL METHODS

These methods ask: “What does it look like?” –

The “it” ranges from subcellular components to whole brain. Examples of four techniques are:

A frontal section of a cat brain, stained with cresyl violet, a cell body stain. Arrowheads point to examples of some “nuclei,” which are groups of cell bodies (note dark purple stain). The lighter, nearly white areas are groups of axons.

Note visibility of subcellular

components.

(Both figures were adapted from Carlson, NR, 2001.)

~2 mm

Some important terms:Cytoarchitecture: the structural arrangement (‘architecture’) of groups of cellsHistochemistry: methods that allow us to visualize molecules in tissues, using special ‘stains,’ fluorescent dyes, and radioactivity (autoradiography). See p. 143-Methods 5.1


A synapse - and its cleft

Cross section through axons

--LIGHT MICROSCOPY

--ELECTRON MICROSCOP

Y

~ 2 цm ~ 1 цm ~ 2 цm

Class # 8: Meth&Eth, p. 5

--CAT scans

--MRI imaging—see p. 106, 107:Fig.4.30

ANATOMICAL METHODS (cont’d)

ANATOMICAL METHODS (cont’d)“Neuronavigation”

Neuroscientists & clinicians need to be able to communicate in a standardized way about parts within the brain. The

‘stereotaxic device’ was invented for that purpose. The brain is positioned in a standard orientation, and then sliced is 3

planes, creating an ‘atlas.’ (see fig. 4.35 in your book, p. 110)


Adapted from: Wilson JF. Biological Foundations of Human Behavior. Wadsworth/Thompson Learning, Belmont, CA, 2003.

ANATOMICAL METHODS (cont’d)“Neuronavigation”

From: Wilson, JF Biological Foundations of Human Behavior. Wadsworth/Thomson, Belmont, CA, 2003, p.123


FUNCTIONAL METHODS


These methods ask questions about functions:

What does it do? How does it work?

There are three general categories of such methods:

(1) Genetic and molecular biological methods

(2) Neurochemical methods

(3) Monitoring the nervous system’s “activity”

(4) Experimental manipulation of neural tissue and assessing the effects on behavior: lesions and stimulation

FUNCTIONAL METHODS (cont’d)(1 & 2) Genetics, molecular biology, &

neurochemistryThere are in general two types of genetic methods: those that examine how heritability influences function, and those that examine how gene expression (i.e.,, the production of proteins) influences functions.

Heritability: see Module 1.2 (p. 14-16).

Gene expression:

At the molecular and cellular level, these methods include assessments of how the transcription & translation of neuroactive agents and their receptors in neurons and glial cells is controlled.

Techniques (mostly neurochemical): molecular biol.; histochemistry (immunohistochemistry)

At the physiological and behavioral levels, these methods include assessments of how alterations in the transcription & translation of neurotransmitters and their receptors influence behaviors.

Techniques: behavioral tests

At all of these levels, an important experimental manipulation is called the knockout model, which involves eliminating a single gene to examine its role in the production of neuroactive agents, their receptors, and behavior.


FUNCTIONAL METHODS (cont’d)

(2) Neurochemistry-Example


We wanted to know if abnormal structures in the body (abnormal growths from a condition in women called “endometriosis”) contained nerves. So, we used a procedure called “immunohistochemistry” to see if the structures contained “markers” for different kind of nerve fibers. We discovered that the structures did indeed contain nerve fibers: both sensory and autonomic sympathetic nerves. Because we were the first people to discover this, the paper was published in Science: (Berkley KJ, Rapkin AJ, Papka RE. The pains of endometriosis. Science 2005;306:1587.)

Netter 1965

FUNCTIONAL METHODS (cont’d)(3) Monitoring the nervous

system’s ‘activity’ (see also: p. 40-Fig. 2.13;, 247 in book)


FUNCTIONAL METHODS: (3) Monitoring activity (cont’d) Example: recording activity of single neurons in the

brain with microelectrodes (see also p. 164 in book)

FROM: Peng W, Dmitrieva N, Berkley KJ. 2002.

brush the skin

stimulate pelvic organs

bladder cont cervix colon vaginaexcite inhibit delayed excite excitateuterus-no response (not shown)

CVX

VAGCOL

blad.contr.

Responses of neurons to stimultaing the organs

record in the gracile

nucleus


FUNCTIONAL METHODSs: (3) Monitoring activity (cont’d) Examples: PET and MEG

These images from a show activity in your instructor’s brain when her bladder was very (very) full! (To be explained in class.)

PET: see p.

72-Fig.3.19 and p. 108 in your book

MEG: see p. 108 in your book


FUNCTIONAL METHODSs (3) Monitoring activity (cont’d):

Functional Magnetic resonance imaging (fMRI)-p. 108 & Fig. 4.34


Copyright ©2006 American Physiological Society

Berman SM, Naliboff BD, Suyenobu B, Labus JS, Stains J, Bueller JA, Ruby K, Mayer EA. Sex differences in regional brain response to aversive pelvic visceral stimuli.Am J Physiol Regul Integr Comp Physiol. 2006 Aug;291(2):R268-76.

Response to 45-mmHg distension of the rectum

FUNCTIONAL METHODS(4) Manipulation of the brain:

lesions & stimulation (see also p. 130 in book)

Some of our earliest understanding of brain function came from

analyzing the effects of destruction of the brain due to gunshot wounds

or other injuries:

From: http://www.epub.org.br/cm/n02/historia/phineas.htm

Example: The Story of Phineas Gage


FUNCTIONAL METHODS (cont’d)(4) Manipulation of the brain: lesions &

stimulation Phineas Gage was a young railroad construction supervisor in Vermont. In September 1848, while preparing a powder charge for blasting a rock, he inadvertently tamped a steel rod into the hole. The ensuing explosion projected the rod against his skull, at a high speed. The rod entered his head trhough his left cheek, destroyed his eye, traversed the frontal part of the brain, and left the top of the skull at the other side. Gage lost consciousness immediately and started to have convulsions. However, he recovered conscience moments later, and was taken to a local doctor, Jonh Harlow, who took care of him. Amazingly, he was talking and could walk. He lost a lot of blood, but after a bout with infection, he not only survived to the ghastly lesion, but recovered well, too. Months later, however, Gage began to have startling changes in personality in mood. He became extravagant and anti-social, a fullmouth and a liar with bad manners, and could no longer hold a job or plan his future. "Gage was no longer Gage", said his friends of him. He died in 1861, thirtheen years after the accident, penniless and epileptic, and no autopsy was performed on his brain. His former physician, John Harlow, interviewed his friends and relatives, and wrote two, reporting Gage's reconstructed medical history, one in 1948, entitled "Passage of an Iron Rod Through the Head", and another in 1868, titled "Recovery from the Passage of an Iron Rod Through the Head". Phineas Gage became a classical case in the textbooks of neurology. The part of the brain which he had lost, was forever associated to the mental and emotional functions which he had lost. Harlow believed that, "The equilibrium between his intellectual faculties and animal propensities seems to have been destroyed. His skull was recovered and preserved at Harvard University. Much later, two neurobiologists, Hanna and Antonio Damassio of the Univ. Iowa, used computer graphics and neural imaging techniques to plot the trajectory of the steel rod through Gage's brain, and published the results in Science in 1994. They found that most of the damage was to the ventromedial region of the frontal lobes on both sides. The part of the frontal lobes responsible for speech and motor functions was spared, so they concluded that the changes in Gage’s social behavior were probably due to this lesion, because the Damasios had observed similar changes in other patients with similar lesions, causing a defect in rational decision making and the processing of emotion. "Gage's story was the historical beginnings of the study of the biological basis of behavior," said Antonio Damasio. From: http://www.epub.org.br/cm/n02/historia/phineas.htm


FUNCTIONAL METHODS (cont’d)(4) Manipulation of the brain: lesions &

stimulation(see also p. 130 in your book)

Rat with electrode in its brain

LESION/ABLATION: Measure behavior, destroy a part of the brain, measure behavior again.

STIMULATION: Monitor behavior, artificially stimulate (activate) an area of the brain while assessing behaviors presumably elicited by the stimulation.

There are big interpretative problems for both positive and negative results. Experimental design is very important (i.e., control groups). In class, we will discuss the following questions:

(1) If the manipulation affects behavior, does that mean that that part of the brain is involved in that behavior?

(2) If the manipulation does affect behavior, does that mean that that part of the brain is not involved in that behavior?


METHODS OF RESEARCH IN NEUROSCIENCE

CONCLUSIONS:

--All methods have conceptual limitations.

--Therefore, the most satisfying way to answer a research question is to consider results from experiments that test your hypothesis using several different methodological approaches.


Reminder: From your book


TOPIC fig # page #MRI 4.30 106

MEG 4.32 108

Stereotaxic instrument 4.35 110

histochemistry 5.1 143

microelectrode recording 2.13 40

functional MRI (fMRI) 4.34 109

positron emission tomography (PET)

4.33 108

electroencephalography (EEG)

4.31 107

Lesions/stimulation

(example in your book)

4.37

5.20

109-111

145

Class # 8: Ethics&Meth., p. 1 ETHICS & REGULATION of RESEARCH Most everyone agrees that research is...

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