Week 1-Research Methods in Cognitive Neuroscience Flashcards
The Electrophysiological brain: What is the function of the frontal lobe?
Executive functions such as Planning and Problem solving
The Electrophysiological brain: What is the function of the temporal lobe?
Auditory functions such as Language and language perception, Memory and Emotions
The Electrophysiological brain: What is the function of the Occipital lobe?
Visual perception such as Object representation (extracting features)
The Electrophysiological brain: What is the function of the parietal lobe?
Attention, Sensation and Body position
The Electrophysiological brain: What is the function of the basal ganglia?
Movement coordination e.g., riding a bike
The Electrophysiological brain: What is the function of the brain stem?
Physiological functions (e.g., digestion, breathing)
The Electrophysiological brain: What is the function of the cerebellum?
Balance, Coordination, Voluntary movements.
The Electrophysiological brain: What is Korbinian Brodmann’s (1868-1918) key discovery?
-The discovery of 52 Brodmann areas
-Creating greater detail of the brain anatomy based on function
The Electrophysiological brain: What is the Spatio-Temporal Trade off? (Churchland & Sejnowski, 1988)
Some techniques are effective with spatial resolution allowing the neurons to be investigated BUT has a poor temporal resolution (1s) and vice versa with other techniques.
The Electrophysiological brain: How do neurons communicate?
Neurons between each other communicate via electro-chemical signals (at the basic communication level)
The Electrophysiological brain: What is the membrane potential?
-Stable electrochemical gradient (environment) at rest (no communication or stimulus).
-Difference of positive (Na+) and negative (K-) charges between inside and outside environments
-Membrane potential: Vm = Vin – Vout = -70 µV
Vin=voltage in
Vout=voltage out
µV=microvolts
The Electrophysiological brain: How is an action potential generated?
- When the neuron receives a strong signal, the flow of Na+ increases into the neuron, and the flow of K- outside the neuron (becomes a more positive environment internally).
- This affects the general gradient and membrane permeability, enabling depolarisation (i.e., becomes more positive).
- It reaches a threshold (-55mV), causing a rapid upward spike in voltage.
- The positive spike propagates along the axon and is called the “Action potential” (the electrical aspect of brain communication)
The Electrophysiological brain: How do neurons behave as electric dipoles?
-Electric dipoles=battery like
-This creates an electric field along the dipole, which allows conducting the current.
-This in turn creates a magnetic field around the dipole (internal and external cell).
-Every neuron acts as a positive and negative dipole (inside and outside of the neuron)
-This is the electrical properties we use with EEG
The Electrophysiological brain: Who created Electroencephalography? (EEG)
-In 1924 a German psychiatrist Hans Berger developed the electroencephalograph (EEG machine) to record the human brain waves.
-Brainwaves are the total dipole result in brain activity
The Electrophysiological brain: What are modern EEG systems like now?
-Modern systems using soft caps
-EEG measures the summation of electr(ochem)ical activity on the scalp over time by means of recording-electrodes attached to the surface of the scalp.
-EEG provides a useful overview of the electrical activity of the brain.
-Diagnostically EEG is often used in the clinical diagnosis of brain damage and neurological disorders, e.g. epilepsy
The Electrophysiological brain: What activity are Gamma waves associated with?
Hyper brain activity (learning)
The Electrophysiological brain: What activity are Beta waves associated with?
High brain activity (conversation)
The Electrophysiological brain: What activity are Alpha waves associated with?
Initial brain relaxation
The Electrophysiological brain: What activity are Theta waves associated with?
Drifting down into sleeping
The Electrophysiological brain: What activity are Delta waves associated with?
Deep non-dreaming sleep
The Electrophysiological brain: What are some characteristics of Alpha waves?
-Regular - Synchronous
-8 -12 Hz
-High amplitude
The Electrophysiological brain: What does the synchronisation of alpha activity indicate?
It indicates relaxed wakefulness
The Electrophysiological brain: What does the EEG and its electrode measure?
-EEG measures the post-synaptic activity (postsynaptic potentials, PSPS) around the dendrites of pyramidal neurons in the cerebral cortex
-An EEG electrode sums the electrical potentials occurring from many thousands of brain cells.
-One electrode will not capture one dipole but rather is sensitive to the neurons around that one electrode
The Electrophysiological brain: What are the 3 characteristics of Pre-Synaptic Potentials? (PESP)
- Action potential
- Excitatory only
- Fast (advantage)