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Flashcards in Biology and Behaviour Deck (105):
1

Franz Gall

Earliest theories in neuropsychology
-behaviour, intellect and personality could be linked to brain anatomy
-if a trait was well developed, the part of the brain responsible would expand (creating bumps on the head)

2

Pierre Flourens

first person to study the major sections and functions of the brain
-performed extirpations/ablations on rabbit and pigeons + removing parts of the brain and observing the behavioural consequences
-asserted that parts of the brain had specific functions and removing parts weakened the whole brain

3

William James

Known as the father of american psychology
-important to study how the mind functioned in adapting to the environment
-among one of the theories that formed functionalism = system of thought that studied how mental processes help individuals adapt to their environments

4

John Dewey

Wrote an article leading to the inception of functionalism
-it criticized the concept of the reflex arc (breaks the process of reaction to a stimulus into discrete parts)
-Dewey thought that psychology should focus on the study of the organism as a whole

5

Paul Broca

Examined the behavioural deficits of people with brain damage
-specific functional impairments could be linked to specific brain lesions
-discovered Broca's area in the left side of the brain -> damage there leads to inability to speak

6

Herman von Helmholtz

First to measure the speed of a nerve impulse in terms of reaction time
-credited with the transition of psychology into the field of the natural sciences

7

Sir Charles Sherrington

First person to infer the existence of synapses

8

Sensory neurons/afferent neurons

transmit sensory information from receptors to the spinal cord and brain

9

Motor/efferent neurons

transmit motor information from the spinal cord and brain to muscles and glands

10

Interneurons

-most numerous of the 3 types of neurons
-located mainly in the brain and spinal cord
-often linked to reflexive behaviour

11

Reflex arcs

neural circuits that allow muscle action to occur before sensory information has reached the brain
-ex: interneurons of the spinal cord sending pain signals to the legs if you step on a nail

12

Central nervous system (CNS)

brain and spinal cord
-also the olfactory and optic nerves are the 2 pairs of cranial nerves in the CNS

13

Peripheral Nervous System (PNS)

Nerve tissue and fibres outside of the brain and spinal cord
-divided into the somatic and autonomic nervous systems

14

Somatic Nervous system

sensory and motor neurons throughout the skin, joints and muscles

15

Autonomic nervous system (ANS)

Regulates heartbeat, breathing, digestion, and glandular secretions
-involuntary muscle control
-regulates body temp by activation sweating or piloerection
*divided into the sympathetic and parasympathetic branches

16

Parasympathetic Nervous System

Main role is to conserve energy
-resting and sleeping states
-reduces heart rate and constricts bronchi
-increases peristalsis and exocrine secretions as well as bile release

*key neurotransmitter = acetylcholine

17

Sympathetic nervous System

Activted by stress
-increases heart rate and blood glucose levels
-relaxes bronchi and dilates pupils
-redistributes blood to muscles
-decreases digestion and peristalsis

*key neurotransmitter = epinephrine

18

Meninges: function

-protect the brain
-keep brain anchored within the skull
-resorb cerebral spinal fluid

19

Meninges: layers

1. Pia mater: closest to the brain
2. Arachnoid mater
3. Dura mater: closest to the skull bone

20

Cerebrospinal fluid

aqueous solution in which the brain and spinal cord rest
-produced by specialized cells lining the ventricles of the brain

21

3 basic subdivision of the human brain

1. hindbrain
2. midbrain
3. forebrain

22

Brainstem

formed of the hindbrain and the midbrain
-more primitive region of the brain
-contains the brain structures associated with basic survival

23

Limbic system

group of neural structures that are associated primarily with emotion and memory
-eg. aggression, fear, pleasure, pain
-developed later along with the forebrain

24

Cerebral cortex

Most recent evolutionary development
-outer covering of the cerebral hemispheres
-language processing, problem solving, impulse control and long-term planning

25

Midbrain: Structures & Functions

receives sensory information and motor information from the rest of the body

Colliculi = sensorimotor reflexes
-superior : visual sensory input
-inferior : auditory sensory input

26

Hindbrain: Structures & Functions

Cerebellum - refined motor movements

Medulla - vital functions : breathing and digestion

Reticular formation - arousal and alertness

27

Forebrain: Structures & Functions

cerebral cortex - complex perceptual, cognitive, and, behavioural processes

Basal ganglia - movement

Limbic system - emotion and memory

Thalamus - sensory relay station

Hypothalamus - hunger and thirst; emotion

28

The brain develops from the ____ in prenatal life?

Neural tube

29

total swellings in the mature neural tube

5

30

Rhombencephalon

subdivison of the embryonic brain that becomes the hindbrain
-subdivides into the:
myelencephelon => medulla
metencephelon => pons/cerebellum

31

Mesencephalon

subdivison of the embryonic brain that becomes the midbrain

32

Prosencephalon

subdivison of the embryonic brain that becomes the forebrain

-subdivides into the:
telencephalon => cerebral cortex, basal ganglia, limbic system
diencephalon => thalamus, hypothalamus, posterior pituitary gland and the pineal gland

33

Cortical maps

created by electrical stimulation of the cortex and observing the behavioural or perceptual result

34

Electroencephalogram (EEG)

Non-invasive method of measuring electrical activity produced by the brain
-electrodes placed on the subjects scalp
-measures electrical of large groups of neurons
-broad patterns of activity are detected

35

Regional cerebral blood flow (rCBF)

Non-invasive mapping procedure which detects broad patterns of neural activity based on the blood flow to different parts of the brain
-patient inhales radioactive gas
-images of the brain are obtained via MRI, PET or CT scans

36

Thalamus functions

Important relay station for incoming sensory information
-all senses except for smell
-sorts and transmits impulses to the appropriate areas of the cerebral cortex

37

Hypothalamus functions + Parts

Subdivided into the lateral, ventromedial, and anterior

Four F's:
-Feeding
-Fighting
-Flighting
-(sex) Functioning

38

Lateral Hypothalamus functions

Hunger centre
-has special receptors to sense if the body needs more food or fluids
-triggers eating/drinking
*damage to this part results in loss of hunger

39

Ventromedial Hypothalamus functions

Satiety centre
-provides signals to stop eating
*damage usually results in overeating and obesity

40

Anterior Hypothalamus

Control of sexual behaviour + regulation of sleep and body temperature
*damage results in an inhibition of sexual activity

41

Posterior pituitary

Axonal projections from the hypothalamus
-releases hormones: Antidiuretic hormone (ADH) and oxytocin

42

Pineal gland

Important in control of several biological rhythms
-important is the circadian rhythm, regulated by melatonin
-receives direct signals from the retina for coordination with sunlight

43

Basal Ganglia

Group of structures in the middle of the brain
-coordinate muscle movement when signals are received from the cortex
-make movements smooth and posture steady
-relay information to the brain and the spinal cord via the extrapyramidal motor system

*parkinson's involves destruction of parts of the basal ganglia*

44

Extrapyramidal motor system

gathers info about body position and carries this info to the CNS

45

Limbic system

Interconnected group of structures that loops around the central portion of the brain
-amygdala
-septal nuclei
-hippocampus

46

Septal Nuclei

One of the primary pleasure centres of the brain
-association with addictive behaviour

47

Amygdala

Role in defensive and aggressive behaviours (fear and rage for example)
*damage = reduced fear and aggression reactions as well as docility and hypersexual states*

48

Hippocampus

Learning and Memory processes
-consolidation of information & forming of long term memories
-connects with the limbic system via the fornix

49

Anterograde amnesia

Not being able to establish new long term memories

50

Retrograde amnesia

Loss of memories occurring before the brain injury

51

Cerebral cortex

Outer surface of the brain - also called neocortex
-convoluted gyri and sulci provide extra surface area
-whole cerebrum divided into 2 cerebral hemispheres
-cerebral cortex divided into 4 lobes

52

Gyri

Bumps in the cerebral cortex

53

Sulci

Folds in the cerebral cortex

54

Frontal lobe - 2 basic regions + 1 other

1. Prefrontal lobe

2. Primary motor area

* also contains Broca's area

55

Prefrontal lobe

-manages executive function
-supervises/directs operations of other brain regions
-controls processes of perception, memory, emotion, impulse control, and long-term planning
-communicates with the reticular formation in the brain stem for wake/sleep alertness

damage to this area impairs overall supervisory function

*example of an association area*

56

Primary motor area

-located on the precentral gyrus (in front of the central sulcus that divides the frontal and parietal lobes)
-initiates voluntary motor movements
-neurons are arranged systematically according the the part of the body that they are attached to

*example of a projection area*

57

Association area

area that integrates input from diverse brain regions
*ex: prefrontal lobe

58

Projection area

areas that perform rudimentary or simple perceptual and motor tasks
*ex: visual cortex

59

motor homunculus

organizational pattern of the primary motor cortex that shows the relative area that each body part occupies in the PMA

60

Broca's Area

Vitally important for speech production
-usually found in only one hemisphere (dominant one, usually left)

61

Parietal Lobe

Located to the rear of the frontal lobe (divided by the central sulcus)
-central region associated with spatial processing and manipulation

contains the somatosensory cortex (located on the postcentral gyrus) which is the destination for all incoming sensory signals for touch, pressure, temp, and pain

62

Occipital Lobe

Very rear of the brain
-contains the visual cortex (aka striate cortex due to striped appearance under a microscope)

63

Temporal lobe(s) - 2 parts and other functions

1. Auditory cortex
2. Wernike's area

-also functions in memory processing, emotion, and language
-hippocampus is located deep within the temporal lobe

64

Auditory Cortex functions

primary site of most sound processing including speech, music, and other sound info

65

Wernike's Area

associated with language reception and comprehension

66

Contralaterality

when one side of the brain communicates with the opposite side of the body

67

Ipsilaterally

cerebral hemispheres communicating with the same side of the body
-eg hearing

68

Dominant Hemisphere

More heavily stimulated during language reception and production
-Broca's and Wernike's areas are driven by the dominant side

usually the left side
-primarily analytic in function
-language, logic, and math skills

69

Nondominant Hemisphere

Associated with intuition, creativity, music cognition, spatial processing
-assembles the stimulus pieces into a holistic image
-usually the right side
-more sensitive to the emotional tone of language

70

Corpus callosum

connects the two hemispheres of the brain

71

Acetylcholine

Found in both the CNS and PNS
PNS: used to transmit nerve impulses to muscles
-used by the parasympathetic NS and slightly by the sympathetic (sweat glands)
CNS: attention and arousal

72

Epinephrine and Norepinephrine

Controlling alertness and wakefulness

Primary NT of the sympathetic nervous system
-promote fight or flight

Norepinephrine - acts more as a local NT
-low levels = depression
-high levels = mania

Epinepherine - secreted from adrenal medulla to act systematically as a hormone

73

Catecholamines

*important role in the experience of emotions*

Three closely related neurotransmitters
-Dopamine
-Epinephrine
-Norepinephrine

also classified as monoamines or biogenic amines

74

Dopamine

Important in movement and posture
-high concentrations in the basal ganglia
*loss of dopaminergic neurons is associated with Parkinson's

Imbalances play a role in schizophrenia
-dopamine hypothesis: delusions, hallucinations, and agitation arise from too much or too little dopamine

75

Dopamine/Schizophrenia relationship

Treatment of both diseases can result in side effects of the other disease
-Dopamine blockers for schizophrenia can lead to parkinson's like motor disturbances (extrapyramidal side effects)
-l-DOPA increases dopamine levels for Parkinson's patients but an overdose can lead to psychotic symptoms

76

Serotonin

Regulation of mood, eating, sleeping, and dreaming

Is a monoamine or biogenic amine neurotransmitter like the catecholamines

low levels = depression
high levels = mania

77

GABA

Stabilizes neural activity in the brain by producing inhibitory post synaptic potentials
-does so by causing hyperpolarization of the post synaptic membrane

78

Glycine

Inhibitory NT in the CNS by increasing chloride influx into the neuron
-causes hyperpolarization like GABA

79

Glutamate

excitatory NT in the CNS
-acts opposing to Glycine

80

Neuromodulators

also called neuropeptides
-relatively slow, longer effects
-more complex chain of events in the postsynaptic neuron

*endorphins are an example

81

Endorphins

Natural pain killers

82

Brain structure linking the endocrine and nervous systems?

Hypothalamus

83

Hypophyseal Portal System

Connects the hypothalamus and the (anterior) pituitary gland

84

Pituitary gland : functions and divisions

"master" gland located at the base of the brain

Posterior pituitary: ADH and oxytocin release
Anterior pituitary: "master" part of the gland
-releases hormones that control endocrine glands
-controlled directly by the hypothalamus

85

Adrenal glands : functions and divisions

Located on top of the kidneys

Medulla (inside) : epinephrine and norepinephrine, part of the PNS

Cortex (outside) : corticosteroids (like stress hormone cortisol) as well as sex hormones

86

Gonads

Sex glands of the body that produce sex hormones in higher concentrations
-increase libido and mating behaviour/sexual function

87

Innate behaviour

genetically programmed as a result of evolution

88

Learned behaviour

due to experience and environment

89

Adaptive value

extent to which a trait/behaviour positively benefits a species
-increasing fitness, leads to adaptation through natural selection

90

Nature vs nurture

Nature = heredity and inherited behaviours
Nurture = effects of environment/surroundings

91

Family studies limitation

families share both genes and environment which makes it hard to tell which influences a certain behaviour

92

Twin studies

compare concordance rates between monozygotic and dizygotic twins

*concordance rates = how likely both twins are to exhibit the same trait

93

Adoption studies

help to understand environmental influences and genetic influence on behaviour

94

Neurulation

occurs at 3-4 weeks gestational age
-ectoderm over the notochord begins to furrow, forming a neural groove surrounded by two neural folds

95

Neural crest

Cells at the leading edge of the neural fold
-disperse throughout the body to form disparate tissues

96

Neural tube

formed by the closure of the furrow
-ultimately becomes the CNS
-has an altar plate = becomes sensory neurons
-basal plate = motor neurons

*antiepileptic meds are linked to neural tube defects in babies

97

reflex

behaviour that occurs in response to a given stimulus without higher cognitive input

98

rooting reflex

automatic turning of the head in the direction of a stimulus touching the cheek

99

Moro reflex

infants react to abrupt movements of their head by quickly throwing up their arms and then slowly lowering them while crying
-usually disappears after 4 months

100

Babinski reflex

causes toes to spread apart automatically when the sole of the foot is stimulated

101

Grasping reflex

infants close fingers around objects placed in their hands

102

Stranger anxiety

fear/apprehension of unfamiliar people
-appears around 7 months

103

Separation anxiety

fear of being separated from parent
-appears around 1 year

104

Parallel play

children play alongside each other without influencing each other's behaviour
-around age 2

105

Gross motor skill development

proceeds from head (lifting head) to toe (walking) and from core to periphery