NEUROFEEDBACK (MODULATING THE BRAIN THROUGH FEEDBACK)

What is Neurofeedback?
• A form of neuromodulation using real-time EEG to train self-regulation of brain activity.
• Based on operant conditioning: user learns to control certain brain rhythms through feedback.

Brain stimulation methods:

1. Transcranial Magnetic Stimulation (TMS)
2. Transcranial Electric Stimulation (TES)
• Direct current (tDCS)
• Alternating current (tACS)
• Random noise (tRNS)

EEG captures brain activity over time → perfect for studying dynamic connectivity.
• Can reveal functional & effective connectivity (not structural).

fMRI and using fMRI to study language production/comprehension

DTI:

checks what is the water molecules capacity to move in the brain? Can they move freely, or can they only move into one direction?

Color is used to highlight, but it doesn't mean automatically sth going on in this specific region.

MRI:

the stronger the magnetic field, more detailed the images become which means the body can be imaged either at a greater resolution or at the same resolution but faster.

Auditory system:

1. Pinna catches sound waves and deflects them into the external ear canal.

2. Waves are amplified and directed to the eardrum, causing it to vibrate, which in turn vibrates ossicles.

3. Ossicles amplify and convey vibrations to the oval window.

Major strengths and weaknesses of the different brain mapping methods:

Neuroimaging techniques continued..

3. transcranial magnetic stimulation (tms):

It alters the organization of the neural activity in a target cortical area by projecting a magnetic field through the overlying skull.

Neuroimaging techniques continued..

2. Electrophysiology

Direct electrical stimulation of the exposed cortex of neurosurgical patients can reveal language-related regions by temporarily interfering with "naming" and other abilities.

Ready for the neuroimaging techniques?
Here we go..

1. Functional neuroimaging
Hemodynamic. Reason: Relying on the principle that the area engaged with a cognitive task, rapidly receives a surplus of freshly oxygenated blood.

Let's continue with neuropsychology:
- It can identify reliable links between specific linguistic deficits and specific lesion sites.

-the most valuable kinds of neuropsychological data are dissociations:

Some more insights:
Although the human brain comprises 2-3% of total body weight, it devours about 20 percent of the oxygenated blood flowing from the heart.

Arteries-->arterioles-->capilleries (smallest vessel, about 10 micrometers thick- not much wider than a single red blood cell)

So, let's start with Neuroanatomy..