FAQ

Glossary FAQ (Alphabetical Order)

1. Action Potential: 

The rapid electrical impulse that travels along the axon of a neuron, enabling communication.

2. Anterior Prefrontal Cortex (aPFC): 

A brain region involved in complex cognitive functions like moral reasoning and decision-making.

3. Arterial Spin Labeling (ASL):

A non-invasive MRI method that labels arterial blood magnetically to measure cerebral blood flow.

4. BOLD (Blood-Oxygen-Level Dependent): 

A measure in fMRI that reflects changes in blood oxygenation level, correlating with neural activity.

5. Blood-Brain Barrier (BBB):

A protective barrier that regulates the exchange of substances between the bloodstream and the brain.

6. Cathodal Stimulation: 

A form of tDCS that decreases neuronal excitability, often resulting in inhibition of the targeted brain area.

7. Chemical Shift: 

Differences in resonance frequencies of atoms due to their electronic environment, used in MRS.

8. CHESS (Chemical Shift Selective Sequence):

A method to suppress water signals in MRS for better visibility of metabolites.

9. Depolarization: 

The process of reducing a neuron’s membrane potential, making it more likely to fire.

10. Dispersion:

The spreading of electrical current as it travels through tissue, potentially reducing stimulation precision.

11. Doppler Effect: 

A change in the frequency of waves due to the motion of the source or observer, used in ultrasound imaging.

12. Focality: 

The precision of stimulation in targeting a specific brain area, often improved by smaller or specialized electrodes.

13. Fourier Transform:

A mathematical method to convert signals from time or spatial domains into frequency data.

14. General Linear Model (GLM): 

A statistical framework used in fMRI data analysis to model brain activity.

15. Gradient: 

A variation in a parameter (e.g., magnetic field, pressure, or concentration) across a space.

16. High-Definition tDCS (HD-tDCS):

An advanced form of TES using smaller, focused electrodes for precise stimulation.

17. Hyperpolarization:

An increase in a neuron’s membrane potential, making it less likely to fire.

18. Lying Quotient (LQ):

A ratio used to measure deceptive behavior in studies, considering reaction times and accuracy of lies.

19. Magnetic Resonance Spectroscopy (MRS): 

A technique used to measure chemical metabolites in the brain.

20. Metabolite: 

A molecule involved in metabolic processes, often studied in MRS to understand tissue biochemistry.

21. Microbubbles: 

Gas-filled particles used in ultrasound for imaging or to temporarily open the blood-brain barrier.

22. Motor Cortex (M1): 

The region of the brain that controls voluntary muscle movements, often used as a reference for TES.

23. Na⁺/K⁺ Pump: 

A cellular mechanism that maintains the resting potential by exchanging sodium and potassium ions.

24. Neural Networks: 

Interconnected groups of neurons which enable communication across different brain regions.

25. N-Acetyl Aspartate (NAA): 

A metabolite used as a marker of neuronal health in MRS studies.

26. Plane Waves: 

Uniform sound waves used in ultrasound imaging for precision.

27. Resistance Monitoring:

Assessing electrical resistance to ensure appropriate current flow during stimulation.

28. Resting Potential: 

The baseline electrical charge difference across a neuron's membrane, essential for action potential generation.

29. Saturation Bands: 

Imaging techniques that suppress signals from specific locations to reduce noise.

30. Sham Stimulation: 

A placebo-like control used in neurostimulation studies to ensure blinding.

31. Short Time Inversion Recovery (STIR): 

An MRI technique used to suppress fat signals for improved contrast.

32. Spatial Resolution: 

The ability to distinguish small details in an image.

33. Spin Echo: 

A technique to refocus magnetic resonance signals for improved imaging quality.

34. Temporal Resolution:

The ability to measure fast changes over time in imaging.

35. tDCS (Transcranial Direct Current Stimulation): 

A non-invasive technique applying a weak electrical current to modulate brain activity.

36. TES (Transcranial Electrical Stimulation): 

A broad term for techniques like tDCS and HD-tDCS that use electrical currents for brain stimulation.

37. T1 and T2 Relaxation: 

Processes describing how excited protons return to equilibrium, influencing MRI signal properties.

38. TMS (Transcranial Magnetic Stimulation): 

A non-invasive method using magnetic fields to induce electrical currents and influence brain activity.

39. Voltage Gradient: 

The variation in electrical potential across a region, influencing ion movement and neuronal activity.

40. Voxel: 

A three-dimensional unit in imaging that represents a volume of tissue.