Final Exam: Chapter 13/14 Flashcards
Circadian rhythms are produced by an endogenous (internal)
mechanism referred to as —-
a biological clock
a free-running rhythm
one that has a period of the body’s own devising.
Free running period is — than 24 hours, you have a — clock
less
fast
Free running period is — than 24 hours, you have a — clock
more
slow
Zeitgeber
a clock-setting cue
ex: exposed to regular light cues
entrained (2)
+signifigance
When a Zeitgeber resets a biorhythm, the rhythm is said to be entrained. When its biological clock is entrained, an animal is able to organize its daily schedule, including when to eat, exercise, and sleep.
Infradian biological rhythm
More than a daily
Ex: Mentrual cycles
Circadian biological clock
Daily
Ex: Human sleep-wake cycle
Ultradian
Less than a day
ex: human eating eating cycles, respiration
humans have a — clock
slow
What is the best zeitgeber and why?
Light: Most obvious cue as to if its day or night, supress melotonin
light in the —- or —– is the best zeitgeber cue
early morning, late evening
The deeper light falls into the night, the —- the effect (2)
+ maximal
bigger
*Maximal around body temp minimal
This is phase —-
advance
This is a phase —–
delay
suprachiasmatic nucleus (SCN) (4)
What is is considered+ location+optic chiasm+divided in 2 regions
- Master biological clock
- a region of the hypothalamus
- just above the optic chiasm
- can be divided into a rhythmic dorsomedial shell region and a non-rhythmic ventrolateral core region
Although the SCN is considered the brain’s master clock, two other neural structures, the —–, also have a clocklike role in controlling behavior.
intergeniculate leaflet and the pineal gland
Melanopsin-containing ganglion cells use — as their primary neurotransmitter but also contain two cotransmitters: substance P and pituitary adenylate cyclase–activating polypeptide (PACAP)
- glutamate
When stimulated by light, melanopsincontaining RGCs are excited, and in turn they excite —
cells in the SCN
dorsomedial shell region of SCN (2)
- rthymic
- contain cells expressing arginine vasopressin (AVP)
When the SCN is lesioned, animals become —
arrhythmic
Ventrolateral core region in SCN
- Contain cells expressing gastrin releasing peptide (GRP) and vasoactiv intestinal peptide (VIP)
- non-rthymic
- entrain the shell neurons, which are rhythmic
The retinohypothalamic tract activates the
core cells
Single cells within the SCN
are rhythmic on their own, however
They are not all in phase with eachother
The increase and decrease in protein synthesis once each day
produce the cellular rhythm. Explain this process to me
cycles takes 24 hr
Cryptochromes (Cry1+2)
* Pair up with Per1, Per2,
and Per3
Period genes
mutation+how many+mutation reason
- 3 period genes
- Mutations in period 2, 3 have been associated with human sleep disorders
- advanced sleep phase syndrome= period 2 (go to sleep earlier than normal & wake up earlier than normal)
- delayed sleep phase dyndrome= period 3 (go to sleep later and wake later)
- the syndrome has to do with changes in level of protein in clock phase period
Cells in the core do not inherently express clock genes but rather act to
relay the incoming photic information from the retina to the rhythmic cell population residing in the shell
If there is a mutation in a single Cry gene, it affects the period of the circadian rhythm. The “period” here refers to the duration of one complete cycle of the circadian rhythm. If there are mutations in two Cry genes (a double mutant), it results in
arrhythmicity
Two enzymes regulates the rate at which per degrades
Tau Mutant hamster has a mutation in
CK1 (E)
Casein Kinase
What it does+how it does it+regulates+shielded
- phosphorylates Per proteins
- Tags per proteins for destruction by adding a phosphate group
- Regulates the rate at which per protein accumulate
- When the Per proteins bind to Cry, they are shielded from CK1
In the taumutant hamsters, per protein acummulate more quickly so it
turns off its own expression sooner
CK1E also helps—- and is a—-
chaperone Per/cry complexes into the nucleus
is a rate limiting step
A mutation in CK1 S has been reported as
Advance sleep phase insomnia
Mutation at the phosphorylation site occurs with CK_
CK E
Insomnia has a —- sleep phase
advanced
Each slave oscillator is responsible for the rhythmic occurrence of one activity. In other words, —-
drinking, eating, body temperature, and sleeping are each produced by a separate slave oscillator.
The SCN clock entrains (appear to depend on signals generated by the suprachiasmatic nucleus to synchronize their time-keeping with that of the suprachiasmatic nucleus) slave oscillators by:
4 ex
similar types of molecular clocks exist in most other peripheral tissues and in many areas of the brain. These clocks, sometimes called slave oscillators
send axonal connections to nuclei close by in the hypothalamus and thalamus. The SCN connects with pituitary endocrine neurons. The SCN also sends indirect messages to autonomic neurons in the spinal cord to inhibit the pineal gland from producing the hormone melatonin, which influences daily and seasonal biorhythms. SCN cells themselves release hormones.
Sleep is determined by accumulation of proteins in our brain such as
adenosine
electroencephalogram (EEG)
described in+electrode+what it records
- a record of brain-wave activity/cortical electrical activity
- Cortical electrical activity
- Described in terms of frequency and
amplitude of waves - Electrodes pasted onto standard locations on the skull’s surface
Electromyogram (EMG)
electrodes+ records what
- Electrodes placed on neck muscles
- a record of muscle activity
electrooculogram (EOG)
Electrodes+ records
- a record of eye movements
- Electrodes near the eyes
REM sleep includes
eye+EEG+EMG+Memory
- rapid eye movements
- an awake pattern in the EEG record
- EMG= muscles are inactive
- Memory function is impaired, so dreams are difficult to remember the next day
Waking state (3)
behaviour+EEG+EOG
- presents behaviour varying from alert wakefulness to drosiness
- the EEG pattern is small amplitude waves with fast frequenct know as beta rhythm (15-30 HZ)
- EOG indicates eye moves
When awake people relax and close their eyes, they may produce the —-, these are—- generated in the region of
- alpha rhythm
- large extremly regular brain waves with a frequency of 7-11 Hz
- Humans generate alpha rhythms in the region of the visual cortex
Slow wave sleep/Non-Rem
EEG+waves
- EEG has increasing amplitude and decreasing frequency
- delta waves
Stage N1 Sleep
EEG waves+frequenct #+ EMG+EOG
- The EEG indicates that beta-wave activity gives way to low-amplitude, mixed-frequency activity, including 4- to 7-Hz theta-wave activity. Concurrently, the EMG remains somewhat active, as the muscles have tone, and the EOG typically indicates that the eyes can be rolling.
N2 Sleep
- continues to produc theta waves but also periodic sleep spindles of 11-16 Hz and K complexes as well ad well defied sharp waves followed by slow waves
N3
- deep sleep, difficult to arose
- EEG is larger amplitude and slow EEG waves called delta rhythms (0.5-2Hz)
- EOG no eye movement
- EMG indicates muscle activity
NREM sleep seems to be more important for —– memories
explicit/declarative
- ex: word learning, spatial larning
- memory of facts/life experience
REM sleep seems to be most important for —- memories
- implicit. nondeclarative memory
- procedure memory on a task
The hormone melatonin, secreted from the — during the dark —–, causes sleepiness
pineal gland during the dark phase of the light–dark cycle
reticular activating system (RAS)
a region at the center of the brainstem, contains a mixture of cell bodies and fiber pathways. RAS stimulation produces a waking EEG, whereas damaging it produces a slow-wave sleeplike EEG.
raphe nuclei
release serotonin for wakfulness
Locus coeruleus
Release norepiniphrine
hypocretin
- found in the dorsolateral hypothalamus
- a signaling molecule to maintain wakefulness. Orexin cells, which are located in the hypothalamus, send projections to many other brain regions
in narcolepsy, these cells die
hypcretin/orexin
Pavlovian conditioning
Learning procedure whereby a neutral stimulus such as a tone (CS) comes to elicit a response (CR) because of its repeated pairing with some event such as the delivery of food (UCS); also called classical conditioning or respondent conditioning
Operant learning
The animal demonstrates that it has learned the association between its actions and the consequences by performing the task faster
Encoding
the process by which info is stored in the brain
Implicit information is encoded in much the same way it is
perceived: it can be described as data-driven, or —- processing.
The idea is that information enters the brain through sensory receptors and then is processed in —
- bottom-up,
- a series of subcortical and cortical regions. For instance, visual information about an object moves from the photoreceptors (the bottom) to the thalamus, occipital cortex, and then through the ventral stream to the temporal lobe (the top), where the object is recognized
Explicit memory, in contrast, depends on conceptually driven, or —–, processing: the person reorganizes the data. If you were searching for a particular object—say, your keys—you would ignore other objects.
- topdown
The frontal lobes are central in —–, whereas the
temporal lobe is central in —-storage of verbal information
short-term memory
long-term
three medial temporal areas take part in explicit memory:
entorhinal cortex, the parahippocampal cortex, and the perirhinal cortex.
A sequential arrangement of two-way connections, projects
from the major cortical regions into the perirhinal and parahippocampal cortices, which in turn project to the entorhinal cortex and then to the hippocampus.
The prefrontal cortex is important for many types of — memory
short-term
Place cells:
fire when organism is in a spatial location, regardless of orientation
Grid cells
fire at many locations, forming a virtual grid of the environment
What happens in habituation?
Delayed response task
Delayed alternation task
Delayed matching to sample task
What happens in sensitization?
