B3.1.4 The Brain

Question 1

Fun fact!

Answer 1

An adult brain contains approx 86 billion neurones

Question 2

5 main areas of brain

Answer 2

Cerebrum- controls complex behaviour such as learning, memory, personality and conscious thought
Cerebellum- controls balance posture and involuntary movement
Medulla- controls automatic actions like heart and breathing rate
Hypothalamus- regulates temperature and water balance
Pituitary gland- stores and releases hormones that regulate many body functions

Question 3

Difficulties when investigating brain function

Answer 3

Patients must give consent to medical info being shared
People who live with brain damage may be unable to agree to experiments so close relatives would have to
Many parts of the nervous system are not accessible and some regions of the brain cannot be treated at all
Accidental damage could lead to speech or motor issues, or changes to personality which are permanent
Several areas of the brain may be involved in a specific function
Some people aren’t willing to take part
Many people believe animal testing is unethical

Question 4

POSITRON EMISSION TOMOGRAPHY

Answer 4

Water containing radioactive oxygen is injected into blood
Moves around body and enters brain
Radioactive water gives off gamma rays which can be detected
Working parts of brain will give off more gamma rays
Researchers can therefore see what parts of the brain are working when patients complete certain activities

Question 5

MAGNETIC RESONANCE IMAGING

Answer 5

Uses strong magnetic fields and radio waves to produce detailed images of the inside of the body

Question 6

COMPUTED TOMOGRAPHY

Answer 6

The patient lies on a bed which passes through a ring of equipment (not into the machine like in MRI). The ring takes a series of x-rays from different angles.
These are processed by a computer to allow the doctors to see inside brains and other parts of the body. (3d images)

Question 7

Disadvantage of CT scan

Answer 7

Cannot be used regularly since x ray radiation increase risk of cancer

Question 8

Disadvantage of mri

Answer 8

Because of these strong magnets, all patients must be carefully screened for metal or implantable electronic devices before they are put into an MRI scanner because the magnets could excite these materials, harming the patient.
Claustrophobic patients
anxiety

Question 9

Advantages of fmri

Answer 9

It is non-invasive and doesn’t involve radiation, making it safe for the subject.
It has excellent spatial and good temporal resolution.
It is easy for the experimenter to use.

Question 10

FMRI

Answer 10

The subject lies down on a flat bed within the MRI machine.
A brief scan is performed to identify the exact location of the brain.
During the fMRI scan, the subject performs specific tasks or stimuli.
These tasks are designed to activate different regions of the brain, allowing researchers to observe changes in blood flow
The fMRI machine captures images of the brain’s activity by detecting changes in blood flow.
This data is collected over multiple time points to create a series of images.
Once the scan is complete, the raw data is processed using specialized software.
This involves aligning the images, removing noise, and statistically analyzing the data to identify areas of increased activity.
They may compare the activation patterns across different conditions or groups to understand how the brain responds to various stimuli or tasks.

Question 11

Disadvantage of FMRI

Answer 11

Brain activity changes extremely fast so fMRI can’t scan fast enough to capture very detailed brain activity.
It can only capture a clear image if the person being scanned stays completely still

Question 12

Disadvantage of pet

Answer 12

A hard time fitting into the PET/CT machine if you are overweight.
Claustrophobia, if you are unable to be in enclosed spaces.
Allergic reactions to a tracer

Question 13

Function of PET

Answer 13

PET scans can be used to check certain brain disorders, such as tumors, Alzheimer’s disease and seizures by detecting brain abnormalities

Question 14

Function of fmri

Answer 14

examine which parts of the brain are handling critical functions
evaluate the effects of stroke or other disease
guide brain treatment

Question 15

Function of mri

Answer 15

to investigate or diagnose conditions that affect soft tissue such as tumours or brain disorders

Question 16

Function of CT

Answer 16

to assess the brain for tumors and other lesions, injuries, intracranial bleeding, structural anomalies particularly when another type of examination are inconclusive.

Question 17

Function of PET

Answer 17

to evaluate organs and/or tissues for the presence of disease or other conditions
most commonly used to investigate confirmed cases of cancer to determine how far the cancer has spread and how well it’s responding to treatment (evaluation)