Lecture 1 Flashcards

1
Q

Behavior is usually considered ____ …i.e., ____.

A

Behavior is usually considered output …i.e., movement.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Behavioral Research Strategies:

A
Describe	behavior thoroughly:
• By	action	
• By	consequence	
• Simple system approach	
•Generate hypotheses about	mechanisms underlying relevant behaviors.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Tinbergen’s Questions About
Causes of Behavior:

4 LEVELS OF ANALYSIS:

A

– IMMEDIATE CAUSATION

– DEVELOPMENT

– EVOLUTION/NATURAL SELECTION

– ADAPTIVE FUNCTION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The task of observing and describing behavior is more difficult than it sounds.

A

As soon as the observer begins to watch and describe behavior, some degree of abstraction and bias is inevitable.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The task of observing and describing behavior is more difficult than it sounds.

This is a result of limitations on time and attention.
4 Reasons

A

– Cannot watch the animals 24 h/day the year around.

– Unable to attend to all aspects of the behavior at once.

– When providing verbal descriptions, the observer must force observations into the structure of a familiar language.

– The diligent behaviorist must always strive for maximal objectivity and breadth in behavioral description.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Animal Models

A

Most of what you learn about the relationships between biological clocks, rhythms, and behavior are outcomes based upon animal research.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

7 Advantages of Animal Models

A
  • Continuity of behavior from one species to another through evolution.
  • Simplest system with qualities of interest.
  • More economical to develop methods on animals that may be useful for people.
  • Ethical considerations; some manipulation are not permissible in humans.
  • Function of behavior often becomes clearer when viewed in a comparative manner.
  • Places human system in perspective.
  • Generalizations can be gained from animal models then tested in humans.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Disadvantages of Animal Models

A

• Enormous Species Differences.
*Behaviors may represent adaptations to very specific environments.

• Huge Behavioral Gap between Animals & Humans.

  • Language & Cultural Evolution.
  • To get the “cleanest” answers about simplest analyses, the less cognition, the better.

• Ethical Considerations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

STRONG INFERENCE.

4 Steps

A

1) Devise alternative/multiple hypotheses.
2) Design & execute experiment that will permit rejection of as many of the hypotheses as possible.
3) Retain surviving hypotheses.

4) Recycle.
*Science advances only by disproofs.
Common Misconception: that goal of scientific enterprise is to develop theories that cannot be disproved.
Wrong.
Marxist, Freudian, Darwinian theories cannot be disproved.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Generic Question in Studies of Behavior

A

What causes Individual X to emit Behavior Z?

• Approach of this class:
– What causes Individual X to emit Behavior Z at time Y?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Chronobiology

A

• Scientific study of biological clocks and their associated rhythms.

• Also called Biochronometry
– Began in the early 1960s
– Had to counteract the dogma of homeostasis in biology and medicine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Core body temperature varies

across the 24h day

A

fghfjt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Chronobiology borrowed terms and concepts extensively from ____ disciplines to describe _____ and their _____.

A

Chronobiology borrowed terms and concepts extensively from engineering disciplines to describe biological clocks and their associated rhythms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

RHYTHM

A

A recurrent event that is characterized by its period, frequency, amplitude, and phase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

PERIOD

A

The length of time required to complete one cycle of the rhythm in question.

– For instance, the amount of time required to go from peak to peak or trough to trough.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

FREQUENCY

A

Computed as the number of completed cycles per unit of time.

– For example, 2 cycles per day.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

AMPLITUDE

A

The amount of change above and below the average value.

– That is, the distance of the peak or nadir from the average.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

PHASE

A

Represents a point on the rhythm relative to some

objective time point during the cycle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Components of Biological

Rhythms

A

??

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Some behavioral rhythms have been recognized since ancient times, but they have generally been attributed to ______ (outside the organism) factors.

A

Some behavioral rhythms have been recognized since ancient times, but they have generally been attributed to Exogenous (outside the organism) factors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Recent evidence indicates that ______ (inside the organism) timing mechanisms
mediate many of the observed rhythms in physiology and behavior.

A

Recent evidence indicates that Endogenous (inside the organism) timing mechanisms
mediate many of the observed rhythms in physiology and behavior.

22
Q

Exogenous Versus Endogenous

Control of Biological Clocks

A

How is it determined whether a rhythm is the result of exogenous factors or an endogenous clock?
– Isolation experiments

Jean Jacques d’Ortous de Mairan found that the tension-relaxation pattern of a
heliotropic plant persisted when isolated from exogenous factors.

23
Q

Jean Jacques d’Ortous de Mairan

A

??

24
Q

Recent Evidence that Biological Clocks are Endogenous

A

– Animals maintained in constant conditions aboard a spacecraft orbiting far above the earth, and presumably away from subtle geophysical cues, display biological rhythms with periods similar to those observed on earth.

– Animals maintained in adjacent, but individual, cages in the absence of environmental cues display biological rhythms with slightly different periods, suggestion that they are not being driven by the same subtle geophysical cue.

– The period (and phase) of the biological rhythms of one individual can be transferred to another individual by means of tissue transplants.

25
Q

Animals maintained in constant conditions aboard a spacecraft orbiting far above the earth, and presumably away from subtle ______, display biological rhythms with _____ similar to those observed on earth.

A

Animals maintained in constant conditions aboard a spacecraft orbiting far above the earth, and presumably away from subtle *Geophysical Cues, display biological rhythms with *Periods similar to those observed on earth.

26
Q

Animals maintained in adjacent, but individual, cages in the absence of environmental cues display biological rhythms with _____, suggestion that they are not being driven by the same _______.

A

Animals maintained in adjacent, but individual, cages in the absence of environmental cues display biological rhythms with *Slightly Different Periods, suggestion that they are not being driven by the same *Subtle Geophysical Cue.

27
Q

The ____ (and ____) of the biological rhythms of one individual can be transferred to another individual by means of _______.

A

The *period (and *phase) of the biological rhythms of one individual can be transferred to another individual by means of *tissue transplants.

28
Q

COMPARISON OF

BIOLOGICAL RHYTHMS

A

• Circadian,
Revolution of planet
– 24 h (22-26h)

• Circatidal,
Tides
– 12.4 h (11-14 h)

• Circalunar,
Phases of the moon.
– 29.5 days (26-32 days)

• Circannual,
Seasons of the year.
– 365.25 days (300-400 days)

29
Q

Circadian

A

Revolution of planet,

– 24 h (22-26 h)

30
Q

Circatidal

A

Tides,

– 12.4 h (11-14 h)

31
Q

Circalunar

A

Phases of the moon.

– 29.5 days (26-32 days)

32
Q

Circannual

A

Seasons of the year.

– 365.25 days (300-400 days)

33
Q

Ultradian Rhythms

A

are shorter than circadian rhythms

34
Q

Infradian Rhythms

A

are longer than circadian rhythms.

They persist in constant conditions, but do not correspond to any known geophysical cue.

35
Q

Usefulness of biological clocks

A

• Synchronizing the activities of animals with their environments (including social environments)
– To prepare for predictable events (e.g., winter, night, etc.).

• Synchronizing the internal physiological and biochemical processes of animals
– To promote efficient functioning

36
Q

Phase Response Curve

A

?????

37
Q

6 General Characteristics of

Biological Clocks and Rhythms

A
  • Inherited
  • Temperature Independent
  • Relatively resistant to the influence of chemicals
  • Entrainment is limited to specific ranges
  • Independent from behavioral feedback
  • Biological clocks are found at every level of organization within an organism.
38
Q

General Characteristics of
Biological Clocks and Rhythms:

Inherited

A

When mutant animals with free-running circadian rhythms >25 hrs are mated with each other, their offspring tend to have longer free-running periods than the offspring of mutants with free-running rhythms <23 hrs (and vice versa).

39
Q

General Characteristics of
Biological Clocks and Rhythms:

Temperature Independent

A

– activities or events that change body temperature don’t significantly alter circadian clocks

– otherwise, there would be speed-ups and slow-downs and eventually all resemblance to a 24hr period would be lost.

40
Q

General Characteristics of
Biological Clocks and Rhythms:

Relatively resistant to the influence of chemicals

A

– If not, the food consumed would constantly be altering biological clocks.

– A few pharmacological	manipulation have been shown, however, to affect clocks:
• Protein synthesis inhibitors		
• Alcohol	(EtOH)	
• Lithium	
• Heavy water (deuterium)
41
Q

General Characteristics of
Biological Clocks and Rhythms:

Entrainment is limited to specific ranges

A

– A circadian rhythm can be entrained to a 23h day by providing 11.5h of light and 11.5h of dark.
(Same for 12.5h light / 12.5h dark)

– However, 10h light and 10h dark does not result in entrainment to a 20hr day.
• Instead, this results in free-running with sporadic entrainment attained at irregular intervals.
• In hamsters, wheel running can be entrained to the following range: 18-26 hrs.

42
Q

General Characteristics of
Biological Clocks and Rhythms:

Independent from behavioral feedback

A

• Independence from behavioral feedback
– Suppose a hamster housed in DD is expressing a 24.25hr cycle of wheel running onset.
– Then, the hamster’s wheel is locked for 10 days.
– Then it is unlocked.

• What time will the hamster begin to run?
– 2 possible predictions:
1) 15min after last time– suggesting that the clock suspended time-keeping while the rhythm of wheel running activity was not being expressed.
2) 150min after last time suggesting that the clock continued to run even in the absence of behavioral feedback.
Prediction #2 is the correct answer.

43
Q

General Characteristics of
Biological Clocks and Rhythms:

Biological clocks are found at every level of organization within an organism.

A

– Single-celled organisms possess circadian rhythms, so the machinery necessary to generate a rhythm must exist at the level of individual cells.

– So, in multi-cellular organisms, does every cell possess its own biological clock?
• Perhaps, but in multi-cellular organisms, it appears as if these individual biological clocks have been organized into some sort of hierarchical fashion with feedback imposed from above.
• E.g., cells taken from hamster adrenals and maintained in culture will free-run at different rates. In the intact hamster, they free-run at the same rate.

44
Q

Master Clocks

A

• Circadian clocks have been isolated after demonstrating that lesions eliminate circadian rhythms.
– Eyes of amphibians
– Pineal glands of fish, reptiles, and birds
– Suprachiasmatic Nuclei (SCN) of the Anterior Hypothalamus in mammals

  • Slices from the SCN maintain circadian rhythms of electrical activity.
  • SCN transplants cause recipient’s rhythm to match that of donor.
  • Environmental light entrains oscillations of SCN
45
Q

Master Clocks in Different Organisms

A

– Eyes of amphibians.
– Pineal glands of fish, reptiles, and birds .
– Suprachiasmatic Nuclei (SCN) of the Anterior Hypothalamus in mammals.

46
Q

_____ are the master clocks in mammals

A

Suprachiasmatic Nuclei (SCN) are the master clocks in mammals

47
Q

Biological Clock Input/Output

A

Light&raquo_space;
PhotoReceptors in the Retina&raquo_space;
Primary Circadian Pacemaker in the SCN&raquo_space; Overt Rhymths

Primary Circadian Pacemaker in the SCN» Pineal Gland&raquo_space; Melatonin&raquo_space; Overt Rhymths

48
Q

Output from clock

A

There are many, but only one has been extensively studied in mammals…

SCN–>PVN–>MFB–>SCG–> Pineal Pathway

49
Q

Pineal Pathway

A

where neural information is transduced into a hormonal message.

50
Q

Are there different clocks for rhythms of different lengths or are longer rhythms simply the result of the multiplication of shorter rhythms?

A
  • E.g., is the 4-day (96h) estrous cycle of a hamster the result of a 4-day clock cycling once or a 1-day clock cycling 4 times?
  • Evaluated in studies of free-running rhythms in female hamsters.

• Phase shifts of entrainment were accompanied by proportionate shifts in estrous cycle.
E.g., Light-dark cycle changed to 25h, then estrous cycle changed to 100h; if reduced to 20h, then estrous cycle switched to 80h.

51
Q

Day length affects Melatonin

A

??

52
Q

Biological Rhythms Affect Physiology

A

??