10- BCI and Emotions

Question 1

What are the 4 main components of BCI (Brain Computer Interface)?

Answer 1

1- A sensing device
2- An amplifier
3- A filter
4- A control system

Question 2

What does an FMRI measure?

Answer 2

Measures change in blood flow (hemodynamic response) while laying in a Magnetic Resonance Imaging machine (MRI).

Question 3

What do changes measured by FMRI indicate?

Answer 3

They indicate intended movement.

Question 4

How does NIRS (Near-Infrared Spectroscopy) measure the same thing?

Answer 4

It uses light close to the infrared spectrum to monitor a response that is similar to FMRI. A pair of illuminators and detectors form channels for signals. Near-infrared rays emit from each illuminator and pass through the skull and brain tissue to be received by the detectors.

Question 5

What is the disadvantage of using NIRS?

Answer 5

Signal/rays have to pass through the skull and brain.

Question 6

What does EEG (Electroencephalography) measure?

Answer 6

Measures voltage fluctuations in the brain. It is non-invasive, just place electrodes on the scalp and they capture electrical brain activity.
(disadvantage)
However, it is hard to localize the signal detected, weak spatial resolution.

Question 7

MEG (Magnetoencephalography) is a better alternative than traditional EEG. Explain why.

Answer 7

Because it maps brain activity by recording magnetic fields produced by electrical currents that naturally happen in the brain. It also has more sensors, therefore more spatial resolution than EEG.

Question 8

What brain waves are associated with which emotions?

Answer 8

Positive emotions => Alpha, Beta, Gama
Negative emotions => Delta and theta.

Question 9

What are the current theories about emotions?

Answer 9

• Ekmans theory of six basic emotions (disgust, anger, fear, joy, sadness, surprise)
• Plutchick’s theory of eight basic emotions (disgust, anger, fear, sorrow, joy, acceptance, anticipation and surprise)

Question 10

What if an emotion does not fall in these basic definitions?

Answer 10

They are usually defined as combinations or variations of basic emotions. Non-basic emotions such as frustration, boredom, and confusion can be more useful in HCI.

Question 11

Can a positive experience include negative emotions?

Answer 11

A positive experience can include positive emotions or negative emotions (fear, anxiety) depending on context, for example a horror themed computer game.