Organisation of Brains (Anatomy) & Lab Visit

Question 1

What is the main function of the brainstem?

Answer 1

Basic functions needed for survival: breathing, heart rate, sleep, and eating. Information about these rhythms ascends into cerebellum, basal ganglia and cortex.

Question 2

What is the main function of the cerebellum?

Answer 2

It is the principal sensorimotor organ of the brain. Motor control, motor learning. It coordinates the appropriate contraction of skeletal muscles to produce smooth movements.

It also is closely related to cognitive dysfunctions such as autism.

Question 3

What is the main function of the thalamus?

Answer 3

Sensory information ascends through the thalamus. Cerebellum and Basal Ganglia also enter it, possibly filtering relevant sensory information with respect to context.

Question 4

What is the main function of the hypothalamus?

Answer 4

Maintaining “homeostasis”. It integrates somatic and visceral responses.

Question 5

What is the main function of the cerebrum?

Answer 5

The cerebrum (cerebral cortex) can be divided into distinct areas that are responsible for a variety of high level cognitive functions.

E.g., It is involved in perception, decision making, language, memory, attention, motor control, navigation, imitation,…

Question 6

What is the main function of the corpus callosum?

Answer 6

Corpus callosum is white matter that connects the two hemispheres

Question 7

What is the main function of the frontal lobe?

Answer 7

Executive control of behavior, complex learning. The primary motor cortex (precentral gyrus) is also located in the frontal lobe.

Question 8

What is the main function of the parietal lobe?

Answer 8

Integrating sensory information. Involved in spatial perception (the “where pathway” projecting from the visual cortex) - processing the object’s spatial location relative to the viewer.

Also involved in language acquisition.

Question 9

What is the main function of the occipital lobe?

Answer 9

Processing visual information

Question 10

What is the main function of the temporal lobe?

Answer 10

Processing emotions, language comprehension (Wernicke’s area). It is also involved in object recognition (the “what” pathway).

Question 11

How do delay conditioning and trace conditioning differ?

Answer 11

In delay conditioning, the conditioning stimulus (e.g., sound) is continuously presented for a certain duration (delay) until the unconditioned stimulus.

In trace conditioning, the conditioning stimulus presentation is short, and there is a silent interval until the unconditioned stimulus appears.

For example: in the Eye-blink conditioning experiment, delay conditioning means that the light turns on before the air puff and stays on until the puff is delivered. In trace conditioning, the conditioned stimulus begins and ends before the unconditioned stimulus is presented. The memory of the stimulus is involved in trace conditioning, whereas in delay conditioning we talk about measuring an interval.

Question 12

What is a presynaptic neuron?

Answer 12

A presynaptic neuron sends a signal (neurotransmitters) to a postsynaptic neuron.

Question 13

What is a postsynaptic neuron?

Answer 13

The postsynaptic neuron is the neuron that receives a signal from a presynaptic neuron.

Question 14

What is the type of neuron depicted in this picture?

(image source: Walter, Röhrbein, & Knoll, 2015)

Answer 14

A pyramidal cell.

Question 15

What is electrophysiology?

Answer 15

Electrophysiology studies electrical activity in living tissues and particularly in neurons.

Question 16

What is physiology?

Answer 16

It is a discipline that studies the functions and mechanisms governing living organisms.

Question 17

What is spike sorting?

Answer 17

Spike sorting is a technique used in the analysis of electrophysiological data.

Spike sorting takes in a signal measured by an electrode (usually noisy) and attempts to find spikes and attribute them to particular sources.

To get an intuition: https://www.youtube.com/watch?v=vSydfDvsewY

Question 18

Which is this brain region?

(image source: http://www.neuroanatomy.ca)

Answer 18

Corpus Callosum

Question 19

Which brain region is the arrow pointing at?

Answer 19

Amygdala

Question 20

Which part of the brain is the arrow pointing at?

(image source: http://www.neuroanatomy.ca)

Answer 20

Thalamus

Question 21

Which brain region is the arrow pointing at?

(image source: http://www.neuroanatomy.ca)

Answer 21

Hippocampus

Question 22

Which brain region is the arrow pointing at?

(image source: http://www.neuroanatomy.ca)

Answer 22

Thalamus

Question 23

What data is acquired with extracellular recordings?

Answer 23

**Spikes* and the local field potential (LFP)

Question 24

What is in this picture?

(image source: https://www.imsbio.co.jp)

Answer 24

A raster plot. Spikes appear as dots. X-axis tends to be time. On the y axis each row is one neuron (or trial).

Question 25

What data are depicted in each of these panels?

Answer 25

Raw trace (the ‘electrical potential over time, with spikes)

Spike Raster (spikes plotted over time, where rows are usually trials or neurons)

Peristimulus time histogram (spike counts in bins around a stimulus)

Question 26

Which of the following methods would you choose in order to study the resting-state activity of the brain?

(a) Electrophysiology
(b) Calcuim imaging
(c) Functional ultrasound
(d) fMRI

Answer 26

Both (c) Functional ultrasound and
(d) fMRI. Can you tell why?

Question 27

Define what is meant by tetanizing an input.

Answer 27

Producing a high frequency, prolonged input to a sensory system or neuron.

Question 28

What is the role of tetanizing input to a synapse?

Answer 28

To study plasticity such as LTD (Long Term Depression) or LTP (Long Term Potentiation)