Biological Bases of Behaviour Flashcards
(95 cards)
1
Q
Alan Hodgkin and Andrew Huxley
A
- Studied axons by removing them from squid.
- Wanted to know: “What is the nature of a neural impulse?”, “What happens when a neuron is stimulated?”
2
Q
Donald Hebb
A
- Focused on how neurons link together to form networks (cell assemblies) and that they could not influence behaviour alone. It was the assembly that was most important.
- Learning happens when neuron stimulation repeatedly creates a change in the synapse.
3
Q
Candace Pert and Solomon Snyder
A
- Did studies relating to morphine and found out that it exerts it effects by binding to receptor sites in the brain.
- They learned that the brain has receptor sites for this drug since it has a morphine like substance that is produced: endorphins
4
Q
Wilder Penfield
A
Gifted neurosurgeon who was able to study and map the functions of the brain by performing brain surgeries on patients who were conscious.
5
Q
James Old and Peter Milner
A
Discovered that animals will search out and preform actions that would stimulate their brains. They inferred that the animals were experiencing pleasure when they did this.
6
Q
Doreen Kimura
A
Believed cognitive differences in gender (such as males’ better spatial ability and females’ better verbal abilities) may be caused by sex hormones in early development
7
Q
Charles Darwin
A
- Naturalist who first explained natural selection
- 4 insights:
1. organisms vary in endless ways
2. some characteristics are inheritable
3. organisms produce offspring at rates that the environment cannot support
4. when specific traits support an organisms survival or reproductive success, those who possess it tend to have more offspring, thus increasing its prevalence in the population over time
8
Q
Roger Sperry and Michael Gazzaniga
A
- Studied split-brain patients
- Found that subjects could verbally identify a picture that was flashed in their right visual field (left hemisphere) but could not in their left visual field (right hemisphere)
- Supports theory that the left hemisphere is crucial in language and that the right hemisphere is better at visual-spatial tasks
9
Q
Absolute Refractory Period
A
Period of time following an action potential in which another one cannot be performed
10
Q
Action Potential
A
- Shift in an neuron’s charge that travels along an axon
- Occurs when channels in the cell membrane open, allowing positive sodium ions into the cell
- Different neurons carry action potential at different speeds
- ie. thicker axons carry them faster than thinner axons
11
Q
Explain the role of sodium and potassium ions.
A
- Potassium ions are found in the cell and are negatively charged
- Sodium ions are outside the cell and are positively charged
- The act of sodium ions entering the neuron is what causes an action potential
12
Q
Adaption
A
- Traits in a population occurring in order to solve a problem or adapt to their environment
- ie. growing more body hair in order to adapt to a change in climate
13
Q
Adoption Studies
A
Studies done on adopted children to see correlations between traits in relation to their biological or adoptive relatives
14
Q
Afferent Nerve Fibres
A
- Carry information INTO the central nervous system
- Activated by external stimuli
ie. cold air - Called sensory neurons in the peripheral nervous system
- “A” for “Aaah! It’s cold outside, gotta go inside!”
15
Q
Efferent Nerve Fibres
A
- Carry information AWAY from the central nervous system
- Called motor neurons in the peripheral nervous system
- “E” for “Ef away from me, you overgrown maggot!”
16
Q
All-or-None Law
A
- Action potential either happens or it doesn’t
- ie. action potential is like firing a gun, you cannot half-fire a gun
- Action potentials are always the same strength, they only vary in frequency
17
Q
Antagonist
A
A chemical that blocks the effects of neurotransmitters
ie. blocking receptor sites
18
Q
Agonist
A
A chemical that mimics the effect of neurotransmitters
19
Q
Autonomic Nervous System
A
- Contains smooth muscles, glands, heart and blood vessels
- One of the subdivisions in the peripheral nervous system
- 2 branches:
1. Sympathetic Divison
2. Parasympathetic Divison - Controls actions like digestion, heart rate, perspiration etc.
20
Q
Axon
A
- Long, trunk-like structure on a neuron
- Carries action potential to the synapse
- The thicker the axon, the faster the action potential travels
- On certain neurons, the axon is coated in a myelin sheath
21
Q
Behavioural Genetics
A
Studies the influence genetics have on behaviour and characteristics
22
Q
Brain Plasticity
A
- States that the brain is flexible in the sense that it can change structure and function over time
- Studies show that experiences can shape the brain
- ie. certain areas in the somatosensory cortex are enlarged when they receive repeated input from the left hand
- Damage to the brain can lead to neural reorganization
- ie. the occipital lobe in blind people is often recruited to assist with other sensory tasks to compensate for the loss of sight
- Adult brains can generate new neurons through neurogenesis, but the effects of this are currently limited
23
Q
Central Nervous System
A
- Contains brain and spinal cord
- Sends signals to the peripheral nervous system
- Protected by meninges and encased in cerebrospinal fluid, which is also found inside ventricles
24
Q
Ventricle
A
Cavities in the brain filled with cerebrospinal fluid
25
Cerebellum
- Literally "little brain"
- Found inside the hindbrain
- Involved in movement and balance
- Damage impacts motor skills
- May be involved in attention, visual perception and planning
26
Cerebral Cortex
Outer layer of the cerebrum
27
Cerebrum
- Largest portion of the brain
- 2 hemispheres, separated by the corpus callosum
- 4 lobes
1. occipital lobe
2. parietal lobe
3. temporal lobe
4. frontal lobe
28
Cerebral Hemispheres
- Left and right sides of the brain that are specialized in completely different tasks
- ie. Left hemisphere controls the right side of the body and is better at language
- ie. Right hemisphere controls the left side of the body and it better at visual-spatial tasks
29
Cerebrospinal Fluid (CFS)
- Encases the brain and spinal fluid
| - Provides protection and nourishment
30
Chromosomes
- Strands of DNA
| - Each cell has 46 hormones, except sex cells which have 23
31
Corpus Callosum
- Long bundle of nerve fibres that connects the two cerebral hemispheres
- Promotes communication between both hemispheres
32
Critical Period
Limited time period when it is optimal for certain skills to emerge because of the heightened sensitivity to certain experiences
33
Dendrites
Long, branch-like fibers on a neuron that almost but don't quite touch other neurons
34
Dominant Gene
The gene that is expressed when two traits in a gene pair are different
35
Recessive Genes
The gene that is hidden when two traits in a gene pair are different
36
Electrical Stimulation of the Brain
- Sends a weak electric current into different parts of the brain to stimulate them
- Advances understanding in brain-behaviour relationships
37
Electroecencephalograph (EEG)
- Device that records electrical activity in the brain
- Uses electrodes placed on the scalp to monitor activity
- Can be used to see brain patterns that occur when subjects experience different things or perform tasks
38
Endocrine System
- Contains glands that secrete hormones into the bloodstream
| - Controlled by hypothalamus
39
Endorphins
- Chemicals that are similar in structure and function to opiates
- Involved in regulation pain, eating and stress repsonses
40
Epigenetics
- Factor involved in which genes or how much a certain gene is expressed
- Does not change DNA, only phenotypic expression
- Shaped by environment
- Can be inherited
41
Excitatory Postpsynaptic Potential (PSP)
A positive change in voltage that increases the chances of the postsynaptic neuron firing an action potential
42
Family Studies
-Studies done on families to see correlations between relatives in relation to their genes and behaviour
43
Fitness
- An organisms reproductive success relative to the success of others in the population
- Success = number of offspring
44
Forebrain
- Frontal part of the brain
- Largest region
- Contains thalamus, hypothalamus, limbic system, cerebrum etc.
45
Fraternal Twins
- Twins who are born at the same time but originate from different eggs
- No more similar in genetic makeup than regular siblings
46
Genes
Portions of DNA that are inherited
47
Genetic Mapping
- Process of locating each gene on specific chromosomes
| - This allows scientists to see relationships between genes and specific traits or disorders
48
Glia
- Literally "glue"
- Cells found across the nervous system that provide various types of support for neurons
- ie. nourishment, waste removal, insulation
- Also assist in the development of the nervous systems in embyros
49
Heterozygous Conditions
Genes in a pair are different
50
Hindbrain
Includes cerebellum, medulla and pons
51
Hippocampus
- Part of the limbic system
| - Involved in memory and learning
52
Homozygous Condition
Both genes in a pair are the same
53
Hormones
- Secreted by glands in the endocrine system
- Act like neurotransmitters, but they are sent along channels much slower and have vaguer message
- Hormones tend to linger, which leads to us having to "come-down" from a dramatic experience
- Involved in a variety of biological processes such as reproduction, sleep and hunger
54
Hypothalamus
- Located near the base of the forebrain
- Regulates biological needs
- Controls endocrine system
- Critical link between the brain and the endocrine system
55
Identical Twins
- Twins who originated from the same egg
| - 100% genetically similar
56
Inclusive Fitness
- Similar to fitness, but it takes into account self-sacrifice
- Ones own reproductive success + effects one has had on others reproductive success
- The closer the relation, the higher the chance of self-sacrifice
57
Inhibitory Postsynaptic Potential
A negative change in voltage that lowers the likelihood of the postsynaptic neuron firing an action potential
58
Lesioning
The act of destroying a segment of the brain to study its function and the effect it has on the rest of the brain
59
Limbic System
- Network of structures along the border between the cerebral cortex and deeper subcortial areas
- Includes parts of the thalamus, hypothalamus, hippocampus and amygdala
- Regulates emotion, memory, motivation and optimism
60
Medulla
- Attached to spinal cord
| - Involved in unconscious functions such as circulation and breathing as well as reflexes like sneezing or coughing
61
Mutation
- Chemical change in DNA that affects genes
| - These can be passed down
62
Myelin Sheath
Encases axons
63
Natural Selection
- Darwins theory
- Theory that an organism that has a trait that either promotes reproductive success or survival will have more offspring, thus making that desirable trait more prevalent in the population
64
Nerves
Bundles of axons routed together in the peripheral nervous system
65
Neurogenesis
The act of creating new neurons
66
Neurons
Cells in the nervous system that receive, send and incorporate information
67
Neurotransmitters
Chemicals within neurons that transmit message between synapses to other neurons
68
Overextrapolation
Over estimating the effects of something using the little information one has on the subject
ie. Classical music MUST be good for brain development in infants because it improved college students performance for 10 minutes
69
Parasympathetic Divison
- Component of the autonomic nervous system
| - Saves bodily resources by promoting digestion, slowing heart rate and lowering blood pressure
70
Perceptual Asymmetries
Imbalances between the two cerebral hemispheres in relation to how fast they can process different types of stimuli
71
Peripheral Nervous System
- Branches off the central nervous system to arms and legs
- 2 subdivisions:
1. Somatic Nervous System
2. Autonomic Nervous System
72
Phenotype
Physical expression of a gene
| ie. having blue eyes
73
Pituitary Gland
- Small gland that releases a variety of hormones to a large number of places throughout the body
- Stimulates other endocrine glands
- Pituitary is sometimes called the "master gland"
74
Polygenic Traits
Characteristics that are influenced by more than one gene pair
ie. skin colour is said to be influenced by three to five gene pairs
75
Pons
- Literally "bridge"
- Connects brainstem to cerebellum
- Involved in sleep and arousal
76
Postsynaptic Neuron
The neuron that is receiving information from neurotransmitters
77
Postsynaptic Potential
Voltage change at a receptor site in a postsynaptic neuron
78
Prefrontal Cortex
Regulates cognitive, emotional and behavioural functioning
79
Presynaptic Neuron
The neuron sending the action potential
80
Resting Potential
- Neutral state of a neuron
| - Sits around -70 millivolts
81
Reticular Formation
- Nerve pathways connecting to the cerebrum, spinal cord and cerebellum
- Involved in conscious experience
82
Reuptake
The presynaptic neuron reabsorbing the neurotransmitters from the synaptic cleft
83
Soma
- Cell body
| - Contains nucleus
84
Somatic Nervous System
- Subdivision of the peripheral nervous system
- Connects voluntary muscles to sensory receptors
- Requires afferent and efferent nerves to work
- Allows you to move and feel
85
Split-Brain Surgery
- The cutting of the corpus callosum (separation of two cerebral hemispheres)
- Only used in extreme cases on patients who suffer from epilepsy and were unresponsive to other treatment
86
Stem Cells
Undefined cells that have the potential to become any type of cell
87
Sympathetic Division
- Part of the autonomic nervous system
- Prepares the body for emergencies by utilizing the body's resources
- ie. slowing digestion, draining blood from the periphery to lessen bleeding in case of injury
- Triggers the release of hormones in the adrenal glands, preparing the body for action
88
Synapse
The place where messages are sent between neurons
89
Synaptic Cleft
Microscopic gap between the terminal button of one neuron and the cell membrane of another
90
Synaptic Pruning
The act of getting rid of unused synapses to strengthen current ones and provide a unique neural network
91
Synaptic Vesicles
The area in axon terminal buttons where neurotransmitters are stored
92
Terminal Buttons
Areas at the end of dendrites that store and secrete neurotransmitters
93
Thalamus
- Found in forebrain
- All sensory information (except smell) converges here
- Sensory information is sent from the thalamus to the cerebral cortex
94
Twin Studies`
Studies done on identical and fraternal twins to see correlations between heredity and behaviour
95
Zygote
Single celled organism created when sperm fertilizes an egg
