Magna Flashcards
Working vs. Short-term Memory
Working memory and short-term memory are distinct executive functions. While both involve a limited and temporary store, working memory involves the manipulation and processing of information while short-term memory does not.
Central Executive
Central executive, which regulates attention and task switching, and three subsystems, which are controlled by the central executive.
Visuospatial sketchpad
The visuospatial sketchpad is employed when manipulating visual and/or spatial information (eg, reading a map).
Phonological Loop
The phonological loop is employed when manipulating spoken and written information (eg, reading a book).
Episodic Buffer
The episodic buffer is responsible for temporal processing (understanding the timeline of events) and integrating information from long-term memory into working memory (eg, remembering how to multiply when figuring out a tip at a restaurant).
Phi Phenomenon
The phi phenomenon (also known as the motion picture effect) is an optical illusion in which a series of still photographs presented in rapid succession appear to be moving. The phi phenomenon may have been relevant to perceiving motion during the simulation but is irrelevant to depth perception.
Motion Parallax
Motion parallax (or relative motion) is a monocular cue whereby objects in the foreground are perceived as moving faster than objects in the background. Motion parallax is a perceptual process that would not require three-dimensional depth but would still allow subjects to perceive both depth and motion.
Convergence
Convergence is the extent to which the eyes turn inward (converge) to focus on an object; closer objects require more convergence, which helps the brain infer distance. The two-dimensional simulation made the use of binocular cues irrelevant, and neither convergence nor retinal disparity is involved with motion perception.
Retinal Disparity
Retinal disparity occurs because each eye transmits a slightly different image to the brain, which infers distance from the disparity
Speech Shadowing
Speech shadowing is a selective attention (not multitasking) process used in dichotic listening tasks (competing information presented in each ear) that involves repeating information presented in one ear while tuning out the competing information in the other ear.
Interference
Interference is a memory (not attention) process describing when old information prevents recollection of new information (proactive interference) or new information prevents the recollection of old information (retroactive interference).
The Cocktail party Effect
The cocktail party effect describes when attention quickly shifts from an attended stimulus to an unattended stimulus when something significant occurs.
Inertia
An object’s inertia is its resistance to changes in its velocity; objects tend to stay in motion or stay at rest.
Mechanical Advantage
Mechanical advantage is the ratio of the output force Fo to the input force Fi:
and it can be obtained from Work from F1d1 = F0d0
Thermodynamics and Kinetics
Thermodynamics determines whether a reaction can proceed without energy input, and kinetics determines how quickly a reaction proceeds.
Why is oxygen intake elevated after exercise?
Oxygen intake remains elevated after exercise due to the increased demand in muscle cells for oxygen to replenish ATP, creatine phosphate, and glycogen stores and restock myoglobin with oxygen.
Titration Hacks
In a titration, a measured amount of a solution with a known concentration (titrant) is added to another solution containing an unknown concentration of the compound to be measured (analyte). In acid-base titrations, an acid is titrated with a base (or vice versa). The resulting acid-base neutralization reaction produces a change in pH, which is monitored by a pH indicator that signals the equivalence point of the neutralization.
The analyte must be fully dissolved before it can be measured. Sebacic acid has low solubility in water due to a high nonpolar hydrocarbon character. A base will convert the carboxylic acid groups into highly polar ionic salts with much higher aqueous solubility.
Once dissolved, the carboxylate ions can then be titrated with an acid. Subtracting the number of moles of base (such as KOH) in the initial solution from the number of moles of acid (such as HCl) required to reach the equivalence point during the titration will give the number of moles of carboxylate groups from sebacic acid in the sample.
Nernst Equation
A concentration cell employs the same electrode material and ionic solution for both the cathode and the anode, but the ion solutions surrounding the anode and cathode differ in concentration. As a result, the same half-reaction occurs at both electrodes, but it occurs as an oxidation at one and as a reduction (in the reverse direction) at the other. Accordingly, adding the two half-reactions yields a result of E° = 0.00 V. The electrons will migrate from the cell with fewer cations to the cell with more cations until the cation concentration in each cell is equal. Because oxidation occurs at the anode, this is the source of electrons for the cell, which are transferred to the cathode where reduction occurs.
Tonic Stimulus response
Tonic receptors are sensory receptors that continue to produce action potentials throughout the duration of a stimulus. Tonic receptors are limited to the peripheral nervous system and are not found in the brain.
State-dependent memory
State-dependent memory is a phenomenon whereby memory retrieval is most efficient when an individual’s internal state at the time of retrieval is the same as when the memory was encoded. For example, memories encoded while an individual is intoxicated are less easily recalled when sober than when intoxicated at a later time.
Sensory adaptation
Sensory adaptation (or neural adaptation) is a decreased responsiveness of a sensory neuron over time in response to a constant stimulus.
Long-term potentiation
Long-term potentiation (LTP) describes an enduring increase in synaptic transmission of neurons, which is the neural foundation for learning and memory consolidation. When neurons are repeatedly stimulated, they demonstrate an increased firing rate, known as LTP. The increase in magnitude of excitatory postsynaptic potentials (EPSPs) in the postsynaptic neurons in the experimental condition (Figure 1) reflects LTP.
Neuroplasticity
Neuroplasticity (or neural plasticity) refers to lasting changes in the brain that occur when interactions with the environment alter neurons and/or pathways. Neuroplasticity refers to both increases in neuronal connections, known as potentiation, and decreases in neuronal responses, known as depression. Neuroplasticity is highest during early development but continues throughout our lifetime.
Synaptic vs. Structural plasticity
Synaptic plasticity results from changes in the firing rate of the presynaptic neuron, which alters the amount of neurotransmitter released into the synaptic cleft and the number of receptors on the postsynaptic target. Synaptic changes are associated with both immediate and more delayed potentiation or depression.
At the structural level, sprouting (increased connections between neurons), rerouting (new connections between neurons), and pruning (decreased connections between neurons) contribute to structural plasticity. Structural plasticity does not happen quickly, so it is not responsible for immediate changes