Neurscience 2 - Brain Activity

Question 1

Neuraxis

Answer 1

• A line drawing from the spinal cord and through the front of the brain
• Helps denote direction in which the nervous system lies
• Bent as the spine enters the brain

Question 1

Rostal, Caudal, Dorsal, Ventral

Answer 1

• describe when straight, describe when bent

Question 2

Medial, Lateral

Answer 2

• Structures closer to the centre of the brain
• Structures farther away from the centre

Question 3

Lesion Studies

Answer 3

• Examine patients with accidental brain damage to determine both the site of the brain damage and the nature of the functional changes in their behaviour.
• Lesion study in animal is called ablation study.

Question 4

X-Ray Computed Tomography (CT)

Answer 4

• Series of X ray slices of the brain are taken and pieced together to produce relatively quick and inexpensive pictures of the brain.
• Helpful in diagnosising brain injuries and brain tissues
• Non invasively describe the struture of the brain.
• DISADVANTAGE: Low resolution

Question 5

Magnetic Resonance Imaging (MRI)

Answer 5

• Uses magnetic field to image the brain
• MRI is able to determine the difference between different types of tissue (grey and white matter)
• Non invasively describe the struture of the brain.
• DISADVANTAGE: Take much longer and are signifcantly more expensive

Question 6

Positron Emission Tomography (PET)

Answer 6

• Measures the amount of glucose consumed in a particular area of the brain, we would know that it is active.
• Injected with a midly radioactive form of glucose which will fire 2 positrons that can pinpoint the area of the brain active.
• DISADVANTAGE: Radioactive, expensive and not completely non-inavasive.

Question 7

Functional MRI (FMRI)

Answer 7

• When an area of the brain is being used, the capillaries supplying blood to the area will dilate and more O2 molecules will be used up leading to a slight change in magnetic properities of the blood.
• DISADVANTAGE: Blood oxygen response takes some seconds to build up where very short brain events are difficult to measure.

Question 8

Electroencephalogram (EEG)

Answer 8

• When a neuron fires an action potential, the electrial current it produces can be measured at the surface of the scalp where electrodes are attached.
• Deteched epilepsy, different stages of sleep, and relaxed states.

Question 9

Event-Related Potential (ERP)

Answer 9

• specific stimulus is presented to the participant repeatedly while the EEG is recording.
• It generally produces noisy waves, but the specific stimulus presented can have a small and consistent effect across many trials when averaged out, leaving characteristic singles.

Question 10

Cerebrospinal Fluid

Answer 10

• Clear watery fluid in which the brain floats

Question 11

The Hindbrain

Answer 11

• Divided into the myelencephalon (consisting of the medulla) and metencephalon (subdivied into the cerebellum, reticuluar formation and pons)
• These structures are collectively known as the brainstem.
• Though to be the oldest part of the brain as similar strucutres are found in almost all vertebrates –> regulational of vital bodily functions.

Question 12

Cerebellum

Answer 12

• Recieves information from visual, auditory vestibular, and somatosensory.
• Also recieves information from from individual muscle movments and provides corrections to those movmenets by taking into account the infromation from the senses
  – All motor acitivity would be impaired if damaged.

faciliates corredinated movement

Question 13

Pons

Answer 13

• role in movement, auditory perception and emotional processing

Question 14

Medulla

Answer 14

• Involved in the control of the autonomic nervous system (respiration, heart rate, reflexes)

Question 15

Retigular Formation

Answer 15

• Controls the general arousal of the brain in the cerebral hemisphere
• Controls processes such as sleep and wakefulness, sexual arousal, and the ability to concentrate.

Question 16

Midbrain

Answer 16

-

Question 17

Tectum

Answer 17

• Located dorsal to the midbrain and contains center for both auditory and visual processing.
• Visual is known as superior colliculus responsible for visual reflexes and reactions to moving stimuli.
• Inferior colliculus is involved with audiory integration.

Question 18

Tegmentum

Answer 18

• Ventral side
• Contains the red nucleus and the substantia nigra both of which are respnsible for motor control
• Degradation of nurons in this area would leaks to parkinson disease –> motor problems, tremors, rigidity
• Red nucleus plays role in arm movement while walking
• Also released the neurotransmitter dopamine, therefore playing and integral from in reward-related behaviours.

Question 19

The forebrain

Answer 19

• largest region of the brain containing structures inolved in complex functions like emotions, memory, perception snf thought

Question 20

Hypothalamus

Answer 20

• controls and organizes behaviour of autonomic nervous system
• Four F’s: fight, flight, feeding, and mating
• Secretes hormones that control the acitvity of the pituitary gland, therefore it is highly linked to the endocrine system

Question 21

Pituitary gland

Answer 21

• Variety of vital hormones it regulates and releases = endocrine system
• Anterior pituitary gland receives singlas from the brain from the hypothalamus to release stimulating homones.
• Posterior pituitary gland is an extension of the hypothalamus and releases two hormones called oxytocin and vasopression

Question 22

Thalamus

Answer 22

• Symmetrical structure with two lobes.
• Thalamus acts as a relay station between all of the sensory systems expect olfactory

Question 23

Amygdala

Answer 23

• Grouped together with the limbic system
• Involved in learning and storying memories about emotional events.
• Also helps recognize the emotions of other individuals

Question 24

Hippocampus

Answer 24

• Formation of declarative memories (knowledge)
• Connected to the amygdala which is why strong emotions evoke certain memories.
• Region of neurogenesis
• Anmesia if damaged

Question 25

Cortex

Answer 25

• Outerlayer of the brain
• Grooves on the cortex are called sulci, while the larger grooves are called fissues.
• The ridges between the sulci are known as gyri

Question 26

Frontal lobe

Answer 26

• Most complex and least understood of the cortical lobes
• Where most complex desciosn making process occur

Question 27

Occipital lobe

Answer 27

• Responsible only for visual processing
• Mainly simple processing, but also some complex processing as well.
• Damage leads to blindness

Question 28

Temporal lobe

Answer 28

• contains a number of areas responsible for processing some visual stimuli
• Auditory processing beings, mainly for processing memory and lanaguage.

Question 29

Partietal lobe

Answer 29

• processing of touch beings here
• also involved in complex visual and spatial functions
• If section of brain is found damaged, somatorsensory processing, exterceptive (perceiving stimuli outside of our body), interoceptive (perceiving stimuli inside our body) and proprioceptive (controlling body position and balance) functions experience loss or deficit.

Question 30

Corpus callosum

Answer 30

• Joins the two hemispheres of the brain although they operate individually
• Split brain syndrome if damaged
  Ex. Right visual field can do spatial task, while left visual feild can do naming task

Question 31

Asymmetrical Brain

Answer 31

• Specialized function to one side of the brain called asymmetry or brain lateralization
• dissociation damage to specific region on one side of the brain

Question 32

Broca’s area

Answer 32

• Patient “tan” experienced speech deficit
• vital for motor production of speech
• damage leads to expressive asphsia

Question 33

Wernicke’s area

Answer 33

• Language deficit in comprehension
• Damage to the left temporal gyrus
• Leads to receptive aphasia where patient struggles to understand, speak meaningless sentences.

Question 34

Right hemisphere vs left hemisphere

Answer 34

• Specialized in processing spital representations
• Deals with languages