CH 1 BIOLOGICAL INFLUENCES Flashcards
1
Q
The CNS is composed of the…
A
brain
- control and decision making centre of the CNS
spinal cord
- extension of brain stem
- channels communication between brain and peripheral nerves; coordinates reflexes
2
Q
The brain is divided into the…
A
- forebrain (cerebrum, thalamus, limbic system, hypothalamus)
- hindbrain (brainstem, pons, reticular system, medulla
- midbrain
3
Q
discuss the features of the cerebellum
A
- has nerve connections to sense organs and motor cortex
- contributes to making movements and coordinated actions
- makes our movements smooth; not jerky
4
Q
what are the parts of the brainstem?
A
- midbrain: vision and hearing, muscular movement
- pons: eye movement, chewing, facial expressions
- reticular system: sleep, arousal and attention
- medulla: heart rate respiratory rate, blood pressure
5
Q
discuss the features of the spinal cord
A
- highway for messages between brain and rest of body
- involves motor neurons (away from brain) and sensory neurone (towards brain)
- organised into 31 segments
- PNS originates in the 31 pairs of spinal nerves and 12 pairs of cranial nerves
6
Q
PNS nerves
A
- 31 pairs of spinal nerves
- 12 pairs of cranial nerves
- dorsal root: sentry info and ventral root : motor info
7
Q
discuss the key features of the PNS
A
- carries information b/w the CNS and rest of the body (limbs, skin, muscles & organs)
- all the nerves that extend from the SC and brain > carrying msgs to and from various muscles, glands and senses
- divided into somatic NS and autonomic NS
8
Q
SNS
A
- conveys sensory info (from skin, ears, eyes) to the CNS and motor msgs to the muscles
- sensory functions gathers information from the sense receptors across the body > sending info to the brain via spinal cord
9
Q
PNS
A
- Serve to regulate basic life functions (eg. HR, BP, respiration, digestion) and connects the CNS via nerves to internal organs
- Self regulating/involuntary functions
- At work when we experience stress, fear or anger
- separated into sympathetic and parasympathetic
10
Q
SYMPATHETIC
A
- Dominates when under stress/threats (either by physiological or psychological stimuli)
- Activates internal muscles to act quickly (fight or flight response)
- Responses: Pupils dilate (allow more light in), Digestion slowed, Release of endorphins (pain relieving hormones) to prepare for injury, Change in electrical properties of skin (GSR)
11
Q
PARASYMPATHETIC
A
- Maintains the steady state of balanced normal functioning = homeostasis (maintenance of a constant internal env.)
- Regulation of blood sugar levels, waste elimination
- Restores body to calmness after threat
- Decreasing HR, contracting pupils
12
Q
THE NERVOUS SYSTEM
A
- contains all of the nerve cells (neurons) in the body
- individual nerve cell that receives, transmits and
processes information - convey msgs to each other in the form of neural impulses/electrochemical msgs
- basic building blocks of NS
- individual nerve cell that receives, transmits and
13
Q
4 BASIC PARTS OF NEURON
A
- nucleus (control centre)
- cell body (contains nucleus)
- dendrites (receive msgs from other neurons; transmit them toward cell body for processing)
- axon (fibres that carry msg away from cell body - allows info to pass from neuron to neuron)
14
Q
THE NEURON
A
- Axon is covered with myelin sheath
- insulates and protects axons
- speeds up electrical signals
- neurons do not physically connect to another
- synapse = gap between one neuron’s dendrites and another neuron’s axons
- chemicals released at synapse
15
Q
NEUROTRANSMITTERS
A
- chemical substances that carry msgs across the synapse to the dendrite of the receiver neuron
- Instant, very fast action time.
- many drugs target the action of neurotransmitters
- Exercise increases the productions of neurotransmitters (norepinephrine, serotonin, endorphins).
- The excess of neurotransmitters causes a mood boost. eg. “runners high” after vigorous aerobic exercise
16
Q
MOTOR AND SENSORY
A
- motor: convey msgs AWAY from the brain —> TO the skeletal muscles —> movement
- sensory: carry msgs AWAY from axon TOWARDS the brain to be interpreted/processed
17
Q
SYNAPSE ROLE
A
- gap between one neuron’s dendrites and another neuron’s axons
- synaptic transmission relies on chemical balances in the cell and electrical transmission of impulses through the neutron
- chemicals released at synapse are…?
18
Q
MOVING ACROSS THE SYNAPSE STEPS
A
- Action potential/electrical charge travels down the axon to axon terminal/ synaptic knob of the pre- synaptic neuron
- causes calcium ions to enter into the terminal/knob
- his causes the vesicle containing the neurotransmitter to move to the pre- synaptic membrane and release the neurotransmitter into the synaptic cleft
- The neurotransmitter diffuses/travels across the synaptic cleft
- The neurotransmitter attaches to receptors on the postsynaptic membrane
- This initiates the post-synaptic neuron to move potassium and sodium ions across the membrane.
- Generating another action
potential
19
Q
SERATONIN
A
- Involved with the onset of sleep and moods.
- Used in medication for people suffering severe depression.
20
Q
DOPAMINE
A
Involved in complex bodily movements
Regulating emotional responses – particularly pleasure and excitement
Used in the medication for people with Parkinson’s disease – which is characterised by muscle tremors and difficulty in initiating movement.
21
Q
NORADRENALINE
A
- help body deal with danger
- memory retrieval
22
Q
ENDORPHINS
A
- regulate feelings and perceptions of pain
- natural pain killing drugs
- released when you experience a +ive mood
23
Q
FRONTAL
A
- primary motor cortex (control of movement)
- most complex mental behaviours = planning, problem solving, thinking, memory, learning and analysing
- control of voluntary movement
- left part - Broca’s Area (language!) controls muscles of throat, mouth, jaw, tongue and face
- if damaged, individuals personality and emotional life may change
24
Q
PAUL BROCA’S AREA
A
- examined brains of 2 patients that lost speech
- common area of damage
- concluded: area controlled speech!
- deficit in language called Broca’s aphasia
25
Q
PARIETAL
A
- primary somatosensory cortex (processes sensory info)
- sense of touch
- motion detection in the environment/ location of objects in space
- spatial awareness
- enables individuals to read, write and solve maths problems
- important for processing of sensory info (touch, temp, pressure)
26
Q
OCCIPITAL
A
- primary visual cortex (processes incoming visual sense info)
- procession of visual info (seeing colours, perceiving and recognising diff. animals, objects and ppl)
27
Q
TEMPORAL
A
- primary auditory cortex (received signals from ear receptors; sound processed)
- processing auditory information
- 2nd most important language centre - Wernicke’s area
- comprehensive of speech, formulation of sentences
- memory
- facial recognition
- object identification
- emotion
28
Q
CARL WERNICKES AREA
A
- proposed a link between left upper temp. lobe and mimicking words and syllabus associated with images of spoken words
- wernicke’s aphasia: condition where language comprehension impaired, but speech production normal
29
Q
ROLE OF GENETICS
A
- Heredity: The process of passing characteristics from one generation to another
- individuals receive their genes from their parents
- this occurs when the sperm and egg meet and join to become a zygote
- hereditary info contained in 46 chromosomes, made up of genes (“recipe’s” for development)
- heredity sets limits but the environment determines how things turn out within those limits
30
Q
HOW DO GENES AFFECT US
A
these genes affect
- how we develop physically - eye/hair/skin colour
- pace and timing of dev.
31
Q
HORMONES
A
- Hormones are chemical messengers produced by the endocrine glands.
- They travel via the bloodstream.
- Produce slow messages.
- Target non-nerve cells
- Produce outcomes related to things such as: Food
Sex Moods Growth - Adrenal gland important = produces adrenaline & nor- adrenaline
- work in conjunction with SNS - speed up bodily reactions to danger
32
Q
ADRENALINE
A
- Produces hormones related to ‘flight’ or ‘fight’ - do you run away or do you stay and fight.
- Helps to deal with emergency situations
- Reactions: muscle contraction, increased resp, increased HR, dilation of pupils
33
Q
ADRENALINE: BEHAVIOUR, EMOTION AND THOUGHT
A
- Behaviour: enhances physical strength
- Emotion: anxiety or depression, agitation
- Thought: hormonal imbalances can lead to many mental health issues such as depression
- Brain’s reaction to stress: makes the individual more fearful
34
Q
NORADRENALINE
A
- keeps us alert
- modifies state of target organs to make it more conducive to active body movement
- increases the rate and force of the heartbeat
35
Q
NORADRENALINE: BEHAVIOUR, EMOTION AND THOUGHT
A
- Behaviour: promotes stress avoiding behaviours
- Emotion: depression, anxiety, post-traumatic stress disorder; euphoria (small bursts)
- Thought: affects attention and focus
- Brain’s reaction to stress: makes the individual more alert/more aroused
36
Q
TYPES OF PSYCHOACTIVE DRUGS
A
- Depressants: ‘downers’ calm the nervous system and slow body functions.
- Stimulants: ‘uppers’ excite the nervous system and arouse body functions.
- Hallucinogens: change or perceptions and give us sensory images without input from the senses.
37
Q
DEPRESSANTS
A
- ALCOHOL
- Most commonly used recreational drug in Australia.
- Is a depressant: it reduces feelings of self-consciousness and promotes relaxation.
- Leads to ‘disinhibition’ leading individuals to behave in ways that they would not normally do.
- Alcohol affects motor control and hence the problems with drink driving.
38
Q
STIMULANTS
A
- CAFFEINE & NICOTINE
- increase heart and breathing rates
- increased energy and self-confidence levels
- used to stay away, lose weight and boost athletic performance
39
Q
HALLUCINOGENS
A
- Mind altering drugs
- Change perceptions —> vivid images
- Can be natural (marijuana) or synthetic (LSD)
- Effects: reduces inhibitions, increases sensitivity to sounds, colours, tastes and smells
- LSD; “trip” effects: euphoria with intense pleasant images or intense terror and panic
40
Q
CEREBRUM
A
- controls motor and mental activity
- divided into left and right hemisphere
