NA and NP (6) - language, memory and sleep Flashcards
What is dual innervation in regards to the visceral organs?
The parasympathetic and sympathetic works in opposite directions
Ex. For the heart;
- PNS; slowing, restful effect
- SNS; heart rate speeds up
Ex. For the GI system;
- PNS; Stimulatory (digestive)
- SNS; Inhibitory (digesting food is not so important when SNS is activated)
What is an example of a cooperative effect?
Regulation of the external genitalia during intercourse
- PNS; dilation of blood vessels in penis to allow for erection
- SNS; drives the process of ejaculation
What are examples of actions handled by only one branch of the ANS (either sympathetic or parasympathetic)
SNS; Vascular tone = blood vessels are kept in a state of partial vasoconstriction (somewhere in the middle of being constricted and dilated), regulation of blood vessel diameter is only SNS NOT PNS
PNS; the heart = at rest it has a tonic slowing effect on the heart at the level of the sinoatrial node (the pacemaker of the heart that sets the rate at which the heart contracts)
List some examples of organs that use SNS regulation only
Adrenal medulla, sweat glands, arrector pili (goosebumps), muscles of hair follicles, kidneys, most blood vessels
What is the result when renin is released from the kidneys?
Increased blood pressure - activatesthe production of angiotensin II (a potent vasoconstrictor)
Where can ACh be found to be released?
Released by all preganglionic axons in both the PNS and SNS, as well as all postganglionic fibers in the PNS
what are the 2 types of cholinergic receptors that bind ACh?
Nictinic and muscarinic
Describe nicotinic receptors
Found on motor end plates (somatic NS skeletal muscle), all ganglionic neurons of both SNS and PNS, hormone producing cells of the adrenal medulla
ACh binding to nicotinic receptors is always stimulatory
Describe muscarinic receptors
Found on all effector cells innervated by postganglionic cholinergic fibers (essentially all PNS target organs)
Depending on the subclass of the receptor, ACh binding to muscarinic can be either stimulatory or inhibitory
What receptors are associated with NE?
Adrenergic receptors; NE is released only by postganglionic fibers of SNS
alpha and beta tyes
effects can either be stimulatory or inhibitory based on receptor subtype and organ
What would be the result of damage to either Broca’s area or Wernickes area?
Broca’s; can understand language but have difficult speaking (maybe also with written language and sign language)
Wernicke’s; can speak but speech is often a ‘word salad’ and have trouble understanding language
What is the correlation between Broca’s area and Wernicke’s area?
Both areas interact with basal nuclei in order to create a language implementation system
This system analyzes both incoming and outgoing word sounds and grammatical structures
Links with surrounding cortical structures that are involved in the more complex functions of concepts and ideas
Motor areas on the right side are involved in body language (gestures/tone of voice/understanding the emotional context)
What is memory ?
The storage and retrieval or information
What are 4 types of memory? Subclasses within them (if any)?
1) Declarative = fact based memory (words, dates, names, faces)
- Short term (working) memory - temporary (15-30s) and limited
- Long term (storage) memory - limitless capacity but can forget things with time
2) Procedural = skill based memory (playing an instrument, typing)
3) Motor = riding a bike
4) Emotional = putting emotional value on something (feeling fear when you hear what sounds like a gun)
What are some factors that may influence what we store in our LTM?
- emotional state (release of NE) = we tend to remember things better if there was a strong emotionl value connected to it
- rehearsal
- association (linking and connections)
How does permanent transfer of info to LTM occur?
Requires consolidation - considerable passing info from various cortical areas through the hippocampus
Hippocampus sorts them by comparing with previous recorded ones and creates associations
Associations are sent back to be stored as memory traces
Through repetition and use of mnemonic devices, this info is sent back to the hippocampus repeatedly and the hippocampus continues to strengthen the associations
What is skill memory? What are its results?
Involves motor activity (physical activity) and is acquired through practice
Communication between basal nuclei and premotor cortex
Release of dopamine by the substantia nigra
Results = connections between a stimulus and a motor response
What is an EEG and what is its function?
EEG = electroencephalogram
Records neural activity through continuous electical activity of neurons
Meaures voltage differences between various cortical areas and are recorded as brain waves (Hz)
What are the 4 types of brain waves?
1) Alpha waves (8-13Hz); regular and rhythmic
2) Beta waves (14-30Hz); rhythmic but less regular and higher frequency
3) Theta waves (4-7Hz); more irregular
4) Delta waves (4Hz>); high amplitude, deep sleep and when RAS is suppressed
What are 4 levels of consciousness?
Alertness, drowsiness (lethargy), stupor, coma
What is the difference between a coma and deep sleep ?
Deep sleep = brain remains active and oxygen consumption is similar to awakened state
Coma = oxygen consumption is significantly reduced
What is REM? NREM? what happens during REM sleep?
REM = rapid eye movement
NREM = non-rapid eye movement
Most dreaming usually occurs during REM sleep , usually has a higher rate of use of oxygen
What is the hypothalamic suprachiasmatic nucleus?
Our biological clock (we follow a 24hr circadian rhythm)
- it inhibits the RAS so less stimulations goes to the cortex allowing us to relax and fall asleep
What is released as we awaken from sleep?
orexin peptides
also a release of cortisol by adrenal cortex (however instead of the usual stress responses, cortisol release at this time increases alertness and readiness to wake up)
What typically happens in our brain during sleep?
We consolidate (establish) new memories
Discard memories no longer accessed
Is restorative as most brain areas can function at a lower level and synapses can be tidied up
What are some examples of sleep disorders?
Narcolepsy; sudden lapsing into sleeep from the awake state at any time of day
- hypothalamic orexins are destroyed by the immune system because the immune system attacks the peptides as if they were a foreign substance
Insomnia; chronic inability to obstain suffient sleep
Sleep apnea; temporary cessation of breathing during sleep (muscle relaxation causes an obstruction of air pathways)
- CO2 levels will build up causing one to briefly wake up to release CO2 and then fall back asleep
