Biological Psychology Flashcards
Structural organisation
Subsections of the nervous system
The central nervous system
The peripheral nervous system
The central nervous system
Spinal cord
Brain
Co-ordination
Integration
Peripheral nervous system
Nerves (outside the brain and spinal cord)
Somatic and autonomic
Motor and sensory
Sympathetic and parasympathetic
Transmission of neurons
The nervous system
- Highly complex part of an animal- co-ordinates its actions and sensory information, -transmitting signals to and from parts of the body.
- The nervous system detects environmental changes that impact the body, then works in tandem with the endocrine system to respond to such events
-produces and relays messages between the brain, spinal cord and a network of neurons.
Subsections of the peripheral nervous system
Somatic
Autonomic
Somatic Nervous System
Voluntary movement of muscles
Have to think about
Stimulatory only
Controls skeletal muscle movement(reflex responses)
Autonomic Nervous System
Involuntary - automatic, subconscious, without thinking, cannot control
Can be stimulatory or inhibitory
Controls muscle movement (not skeletal muscles)
(Internal organs and glands)
Eg.
Heart rate
Blood pressure
Respiration
Digestion
Sexual arousal
Subsections of the somatic nervous system
Sensory
Motor
Subsections of the autonomic nervous system
Parasympathetic
Sympathetic
Central nervous system explained
- carries sensory info up the spinal cord (sensory neurons)
- carries motor messages to the PNS (motor neurons)
Spinal cord
Cable of nerve fibres that runs from the base of the brain to the lower back and connects the brain to the PNS
Peripheral nervous system explained
- carries sensory info to CNS from the body
- carries motor info from the brain to organs and muscles in the body
Autonomic nervous system explained
- carries motor messages from the brain to internal glands and organs - motor neurons
- carries sensory messages to the brain about the activity level of glands and organs - sensory neurons
Somatic Nervous system explained
- carries sensory info received by sensory receptor cells to the CNS - sensory neurons
- carries motor messages from the CNS to skeletal muscles - motor neurons
Parasympathetic
Rest and digest (calming)
- pupils contrict
- salivation
- airways constrict
- heart rate slows
- stomach digests
- intestines digest
- bladder constricts
- reproductive system increases blood flow
Sympathetic
Fight or flight (arousing)
- regulates the glands and internal organs function to physically prepare the body
- pupils dilate
- saliva inhibited
- airways dilate
- heart rate increases
- stomach inhibits digestion
- liver releases glucose
- intestines inhibit digestion
- kidneys release adrenaline
- bladder relaxes
- reproductive system decreases blood flow
Sensory (afferent)
- transmit info to the CNS from sensory organs and receptors within muscles
Eg.
-muscle tension
- pain
- joint angle
- damaging stimuli eg heat or toxins
- adapted or special receptors as hearing and vision
Motor (efferent)
Transmit info from the CNS to cause muscles to contract
Features of a neuron
Dendrites, Soma, axon, myelin, axon terminal
Dendrites
Fibres that receive and convey messages to cell body
Soma (cell body)
Metabolic centre of the cell (contains the nucleus)
Axon
Fibres that conduct electrical impulses away from the cell body
Axon terminal
- Branching fibres at the end of the axon, contains vesicles filled with neurotransmitters.
- Axons branch into hundreds/thousands of axon terminals, which contain vesicles (sacks) of neurotransmitters.
- when a nerve impulse reaches the axon terminals, it stimulates the release of neurotransmitters
Myelin sheath
whitish fatty material called myelin, which insulates the nerve fibre and increases the rate of transmission of the nerve impulse
Synapse
- neurons don’t actually touch each other. The gap between them is called the synapse. (Synaptic cleft)
- Neurotransmitters diffuse across the synapse to continue cell to cell communication.
- Synapses connect neurons and help transmit information from one neuron to the next.
- Places where neurons connect and communicate with each other.
- Is a small gap at the end of a neuron that allows a signal to pass from one neuron to the next.
Three types of neurons
Sensory neuron (unipolar)
Interneuron (bipolar)
Motor neuron (multipolar)
Sensory neuron
Sensory neurons, unipolar.
- process sensory information from the sense organs and carry the sensory messages to the spinal cord ad brain (CNS)
Motor neurons
Motor neurons, multipolar
- carry motor messages from the spinal cord and brain (CNS) to the muscles, glands and organs of the body
Interneurons
Interneurons, bipolar
- act as the connection between sensory neurons and motor neurons and transfers messages from sensory neurons and motor neurons within the CNS.
- Integrate and co-ordinate motor and sensory neurons
- belong in the brain and spinal cord
Direction of transmission
- from the dendrites, to the cell body, then along the the axon to the axon terminals.
- when the action potential reaches the axon terminals, it causes the release of neurotransmitters into the synaptic cleft.
What effects the speed of the action potential in the neuron
The speed of the action potential through neurons depends on the thickness of myelin sheath that covers the axon.
Action potential
‘The electrical impulse’
The electrical impulse that travels along the axon of neurons towards the axon terminals where it causes the release of neurotransmitters into the synaptic cleft.
Electro-chemical signals
- Neurons carry electro-chemical signals, as an electrical nerve impulse travels through the neuron (axon) and neurotransmitters travels between the synapse of neurons.
- the electrical nerve impulse are the ‘electro’ component and the neurotransmitters are the ‘chemical’ component of the signal.
Role of the synapse
Synapse (features )
Synaptic cleft
Synapses connect neurons and helps with the transmission of information from one neuron to the next
Synapse- the axon terminal of a pre-synaptic neuron, the cleft and the dendrite of a post-synaptic neuron
Synaptic cleft- space between two neurons
Neuron communication
(1st to 2d neuron)
(Chemical/electrical)
Pre-synaptic neuron to post-synaptic neuron
Electrical nerve impulse - chemical signal - electrical nerve impulse
Role of neurotransmitters
- a chemical substance which is released at the end of a nerve fibre by the arrival of a nerve impulse and by diffusing across the synapse or junction
- they transmit messages between two neurons or from neurons to muscles
- neurotransmitters diffuse across the synapse to continue cell to cell communication.
- neurotransmitters are chemical messengers that your body can’t function without
-their job is to carry out chemical signals from one neuron to the next target cell
Nerve transmission
Electrical (within the neuron)
Synapse transmission
Chemical (same as the neurotransmitters)
The three major divisions of the brain
Hind brain
Mid brain
Fore brain
Hind brain
-keeping you alive
-helps regulate autonomic functions,
Relay sensory information
Co-ordinate movement
Maintain balance and equilibrium
- coordinates sensory and motor messages entering and leaving the spinal cord and is responsible for balance and coordination
What two main things are in the hind brain
Medulla
Cerebellum
Medulla
The lowest part of the brain stem that relays information between the spinal cord and brain, and regulates the respiratory and cardiovascular system
Cerebellum
Movement, coordination and balance
The convoluted structure at the lower back (posterior) of the brain sitting underneath the cerebrum.
The cerebellum is involved in
- balance
- judging distance
- Co-ordination of fine motor movement
Midbrain
-helps to regulate movement and process auditory and visual info
- receives sensory messages from all senses, except smell, and sends info to the forebrain
The main part of the mid brain
Reticular formation
Reticular formation
- network of nuclei located within the length of the brain stem that helps maintain wakefulness and alertness and aids in the regulation of the sleep-wake cycle
- job is to think and controls things like if you are awake or alert. In the brain stem
Forebrain
- processes sensory information, helps with reasoning and problem solving and regulates autonomic, endocrine, and motor functions
- largest part of the brain that plays a key role in cognition, emotion, behaviour, and processing sensory information
Two main parts of the forebrain
Thalamus
Hypothalamus
Thalamus
- Double-lobed structure located just above the brain stem that receives sensory information, except smell, and transmits info to the cerebral cortex
- the thalamus also has an influence on sleep
Hypothalamus
- structure that sits below the thalamus and regulates sleep, eating, body temperature and sexual drive.
- the hypothalamus also regulates the release of hormones from the pituitary gland that sits beneath it
Cerebral cortex
- the outermost layer of the brain made up of nerve cell tissue that is responsible for higher order processes such as memory, language, reasoning, emotion and decision making
- 2 to 4 mm thick layer of tissues sits on top of the cerebrum and has deep furrows to increase the surface area
- the nerve tissue is comprised of unmyelinated neurons, and the cell bodies of neurons which are collectively known as grey matter
Hemispherical dominance
Left or right side of the brain is dominant and specialise in certain tasks
Contralateral control
Left hemisphere controls the right side of the body, and the
right hemisphere controls the left side of the body
Left hemisphere
Responsible for-
- Producing speech
- comprehending language
- writing
- reasoning
- logical thinking
- mathematical processes
Association in
—memory, selective attention, positive emotions
Right hemisphere
Responsible for
- ability to draw pictures
- spatial orientation
- music and art awareness
- creativity and emotion
-pitch perception, arousal, negative emotions
Frontal lobe
Cognitive function and motor functions
Consciousness, thinking, personality
Voluntary movement, planning and decision making, problem solving, ability to reason, organise information, expression of personality, recognition of emotions, controls speech production and impulse control
Parietal lobe
Movement, senses- taste, speech, reading.
Sensory functions that aren’t in another lobe
-processing sensory information relating to the sense of touch, responsible for spatial awareness, proprioception (perception of the location and movement of body parts), involved with the integration of sensory information (manages hearing, sight, touch, smell and taste)
Occipital lobe
Vision
- visual perception, visual processing, interpreting visual information, facial recognition and perception of distance and depth
Temporal lobe
Hearing, speech. Hearing, smell and memory
Understanding speech, interprets auditory information, responsible for processing the sense of smell, facial recognition, recognising body language, partly responsible for recognition of emotions and involved in long term memory formation
Corpus callosum
Large c shape
joins the left and right hemispheres.
- The thick band of nerve fibres connecting the cerebral hemispheres of the brain and allowing the transfer of information between them.
- This is the largest white matter structure in the human brain with myelinated axons allowing for optimum nerve impulse transmission between neurons.
Broca’s area
controls the ability to speak those words
- muscles to say the words
Wernicke’s area
- Ability to understand the meaning of words
- speech and writing
Pre-frontal cortex
The front layer of the frontal lobes that coordinates executive functions, such as the ability to predict the consequences of behaviours, as well as the ability to recognise and regulate emotions
Primary motor cortex
- frontal lobe at back, motor function
- a strip of cerebral cortex running through the frontal lobes that controls voluntary movement of the body.
- different zones of the primary motor cortex correspond to the various parts of the body, with the size of each zone representing the importance of the body part according to how often used it is
-( back of frontal lobe)
Primary sensory cortex
- A strip of cerebral cortex running through the parietal lobes that registers and processes sensory information
- A human humunculi can be used to visually represent how different zones on the primary sensory cortex correspond to the sensitivity of body part
-( front of parietal lobe)
Primary auditory cortex
- An area within both temporal lobes that registers and processes auditory information that is received from the ears
Primary visual cortex
- An area within both occipital lobes that registers and processes visual information that is received from the eyes
Lateral view
Side (entire brain)
Sagittarius view
Cut half
Superior view
From top
Inferior view
From bottom
What happened to Phineas Gage
- case study illustrating localisation of lobe function. American railroad foreman- survived traumatic brain injury- iron rod shot through his cheek, pierced eye and through his frontal lobe, his skull and obliterated the greater part of the left frontal lobe of his brain.
- Filter to no filter. Personality change - must be in the frontal lobe.
How has Phineas Gage changed and what has his incident made known to us
- He was highly capable, efficient, and polite prior to the incident,
- he was now impatient, impulsive, uncaring for others around him, and would often swear.• Serious damage to the left frontal lobe
• The frontal lobes of the brain are responsible for the expression of personality, problem solving, and impulse control.
What did Walter freeman do
Frontal lobotomies - trying to separate the frontal lobe from other parts
Walter freeman - explained
- prefrontal cortex- frontal lobotomies
Left and right hemispheres
Contralateral control of the body
• He did it to thousands of people- insane mostly but it began to be a thing he wanted to just ‘prevent’ them from going insane
• Inserting an ice pick through the nose, or eyelid to break parts of the bran to separate the frontal lobe. The pick would then be scrambled from side to side in order to damage the frontal lobe from the midbrain. Took about 10 minutes
• Local anaesthetic -only numb a part of the body.
• Frontal lobe and mid brain
• No consent, no science behind it
What did Roger sperry do
Corpus callosum- using split brain experiment
Roger sperry explained
• Split brain research on monkeys and cats before humans. The two hemispheres worked independently of each other, as two split brains, when the corpus callosum connecting them was cut, and that the corpus callosum allowed direct communication between the hemispheres.
• Processing a word with the right eye is processed in the left hemisphere and the person can speak the work they saw. Processing a word with the left eye is processed in the right hemisphere and the person can not speak the word they saw but can draw it.
• The corpus callosum is required for full functioning of the brain, and that the left hemisphere is responsible fro understanding language and speech articulation, while the right hemisphere can recognise language, but is unable to verbally articulate it.
Roger sperry - humans
Performed on a couple of humans to lessen or prevent seizures
Electroencephalogram (EEG)
Is a test that measures electrical activity in the brain using small, metal discs (electrodes) attached to the scalp, detects electrical signals- activity occurring.
Specialises and might be useful diagnosing brain disorders, especially epilepsy or another seizure disorder. Epilepsy, sleep disorders, and brain tumours.
The recorded data is in the form of brain waves- on the computer.
Computed tomography (CT)
Type of x-ray that creates 2 or 3 dimensional images of your body
Bones, organs (brain), soft tissues and blood vessels
Can help diagnose medical conditions including internal injury from an accident
More detail than an ordinary x-ray
Detailed image of any part of the body- bones, muscles, fat, organs and blood vessels
Higher level of radiation.
Magnetic resonance imaging (MRI)
A magnetic resonance imaging - detailed pictures of inside the body
Uses strong magnetic fields and radio waves to generate signals from the body, that are processed by a computer to create detailed pictures
Shows certain problems, injury, or combination with other tests to diagnose a condition
Very detailed, doesn’t use radiation and is painless
Can examine- brain and spinal cord, bones and joints, breasts, heart and blood vessels, internal organs (liver, uterus, prostate gland)
Used for- investigation, diagnosis and planning of treatment of: tumours, joint injury or disease, soft tissue injury, internal organ damage.
Functional magnetic resonance imaging (fMRI)
Measures small changes in the blood flow that occur with the brain activity
It may examine which parts of the brain are handling critical functions, evaluate the effects of stoke or other disease, or to guide brain treatment
fMRI may detect abnormalities within the brain that cannot be found with other imaging techniques
Is a powerful magnetic field, radio frequency pulses, and a computer to produce detailed pictures of internal body structures
Measures the tiny changes in blood flow that take place when a certain part of the brain is working
Learn how a normal, diseased or injured brain is working
Helps asses the effects of stroke, trauma or degenerative disease on brain function
Monitor growth and function of brain tumours
Optic chiasm
The crossing over of optic nerves at the base of the brain, directly in front of the hypothalamus.
• Optic nerves from each eye cross over at the optic chiasm so input from the left field of view is processed in the right hemisphere and input from the right field of view is processed in the left hemisphere.
• This enables vision from one side of both the eyes to be appreciated by the occipital cortex of the opposite side.
