Task 3 Flashcards
The connectionist approach turned away from a ____ system and focused on ____.
Rule-Based
Neural Networks
What is a “Grandmother-Cell”?
According to the notion of local distribution, there are cells that keep knowledge about one specific thing. These basic cells are called “grandmother-cells”
What are advantages of a distributed representation?
- More information can be stored using fewer resources
- Redundancy: If one neuron is lost, information can be retained
What happens, when an auto-associator is prompted with a cue?
It recalls information surrounding the cue
What is the basic motive, that makes a connectionist neural network learn?
Error Reduction
What is something that presently limits the use of BCIs in completely locked-in patients?
Most BCIs today need some sort of neural muscle control
What is the most common method of signal acquisition for BCI and why is this?
EEG – It offers high temporal and acceptable spatial resolution at low invasiveness.
What is something that needs to be improved in order to improve BCIs?
Feature Extraction - Finding a specific physiological aspect in the brain-signal which is associated with the intended behavior
What is a form of EEG, that offers a better spatial resolution without being too invasiveness?
ECoG – Recorded under the dura mater
Explain P300 ERPs and what they are often used for
~300ms after a novel stimulus, there is a positive brain potential. This can be used to communicate with locked-in patients using a grid of letters. When they concentrate on a letter and it becomes illuminated, this stimulus produces a P300 ERP.
What is a problem of implementing BCIs in CLIS patients?
After a while, if no intention is followed by a consequence, intentions seize to exist.
What are ReLU and Sigmoid Functions?
They convert numbers into corresponding values between 0 and 1. ReLU does this linearly, while sigmoid does this with a waveform
What does the output of the cost function signal?
The difference between output and desired solution
