Paper 2 Biopsychology

• Central Nervous System (CNS)


  Orders muscles, glands, organs and processes and interprets info. Consists of brain and spinal cord
• Peripheral Nervous System (PNS)


  Transmit messages via millions of neurons to and from CNS
• Somatic Nervous System (SNS)


  Controls voluntary and involuntary (reflexes) skeletal muscle contractions
• Autonomic nervous system (ANS)

  Regulates glands, blood vessels and internal organs
• Sympathetic Nervous System (SNS)


  Responds to stressful situations, activate flight or fight

  For example:

  - Constrict bowels

  - Decrease salivary production

  - Bladder relaxes
• Parasympathetic nervous system


  Calms down the body to conserve energy, back to homeostasis

  - Relax bowels

  - Increase saliva production

  - Contracts bladder
• Sensory neuron - direction, where, function


  Direction - Skin receptors to CNS

  Where - PNS, tongue, eyes, skin, ears

  Function - Convert info from receptors to neural impulse
• Relay neuron - direction, where, function


  Direction - From sensory to motor neuron and motor neuron to sensory

  Where - Within CNS

  Function - Communication between sensory and motor neurons
• Motor neuron - direction, where, function


  Direction - CNS to muscles and glands

  Where - Dendrites and cell body in spinal cord axon outside spinal cord

  Function - Release neurotransmitters to bind to muscle receptors to trigger movement
• Excitatory neurotransmitters


  Chemicals released from the terminal buttons of a neuron that excite the next neuron into firing (positive charge)
• Inhibitory neurotransmitters


  Chemicals released from the terminal buttons of a neuron that inhibit the next neuron from firing (negative charge)
• Synaptic transmission structure


  1. Presynaptic and postsynaptic neuron

  2. Electrical impulse into the cell body by dendrites and run along axon

  3. Excitatory and inhibitory charge
• Synaptic transmission process


  1. Electrical impulse down pre-synaptic axon and cause vesicles to be released

  2. Neurotransmitters released into synaptic cleft and bind to receptors on post synaptic.
• Synaptic transmission summation


  Whether or not action potential happens depends on summation, only occur if more excitatory in synaptic cleft
• Endocrine system


  Network of glands that secrete chemical messengers called hormones
• Fight or flight response


  Sympathetic NS activated fight or flight and parasympathetic NS takes back to homeostasis
• Plasticity


  Brain can change and develop due to experience and learning (after trauma)
• Synaptic pruning


  Connections not used are deleted and if used frequently strengthened
• Quasi experiment


  Lacks control, IV has not been manipulated but still has 2 conditions
• Brain repairs by


  Axon sprouting - new axon terminals form

  Denervation super sensitivity - axons do similar job become stimulated to higher level to compensate

  Recruitment of homologous areas - areas similar to damaged area do that job
• Mirror box therapy


  Persons with amputated limb use either a mirror or

  mirror box to reflect an image of the intact limb. It is

  hypothesized that this works by preventing cortical

  restructuring.
• Occipital lobe


  Responsible for vision

  Left visual field -> right visual area

  Right visual field -> left visual area
• Temporal lobe


  Auditory area (speech)

  Left ear -> right auditory area

  Right ear -> left auditory area
• Wernick's area


  Left temporal lobe

  Responsible for language understanding

  If damaged nonsense words pronounced, know what to say but say wrong words, no struggle
• Broca's area


  Left temporal lobe

  Responsible for speech production

  If damaged slow, laborious and non-fluent speech
• Parietal lobe


  Somatosensory area (sensory info)

  Pressure, pain, temperature
• Hemispheric lateralisation


  2 halves of the brain function separately and certain mental processes and behaviours controlled by one hemisphere over the other
• Gray (1988)


  3rd response of freeze to avoid confrontation
• Taylor (2000)


  Women 'tend' and 'befriend'

  Protect offspring (tend) and form alliances with other women or attacker (befriend)
• Maguire et al (2000)Study and AO3


  Aim: To investigate whether or not the hippocampus plays a role in human spatial memory

  Procedure: London taxi drivers with a range of age and experience were the participants because their work requires the extensive use of spatial navigational skills, matched pairs design: participants were age and gender matched with a control group, and two different types of MRI scanning were used to assess how the brains of the taxi drivers differed from the control group. It was a quasi-experiment

  Results: showed significantly more grey matter in both left and right hippocampi of the taxi drivers compared to the control group

  Evaluation:

  +No researcher bias

  +No ethical implications

  -Only observed males

  -Only observed 16 matched pairs

  -Nature vs. Nurture debate: did the driving influence the change in the hippocampus, or did their larger than average hippocampus lead them to become taxi drivers?
• Kuhn et al


  Found a significant increase in grey matter in various regions of the brain after participants played video games for 30 minutes a day over a two-month period.
• Mechelli


  Found larger parietal cortex in brains of people who were bilingual
• Bezzola


  - 40 hours of golf training in 40-60 year olds

  - found increased motor cortex activity in fMRI scans compared to control group

  - shows plasticity can occur throughout lifespan
• Medina et al (2007)

  prolonged drug use leads to a lack of connections and risk of dementia
• Schneider and cognitive reserve


  40% with more than 16yrs education had disability free recoveries after brain injury

  10% with less than 12 years education
• Schneider and cognitive reserve


  Asked split brain people to do a series of activities (most had epilepsy)

  3 Conditions:

  - Describe what you see (right visual field can describe, left visual field can't describe)

  - Tactile tests (right hand describe feeling, left hand pick similar object)

  - Drawing tasks (right visual field not clear image drawn, left visual field clear image drawn)
• AO3 Schneider and cognitive reserve


  Small sample - idiographic approach - can't generalise

  Epilepsy may have caused the damage to the brain as all Ps had epilepsy
• fMRI (functional magnetic resonance imaging)


  Brain needs O2, so blood directed to active area, based on magnetic singals
• AO3 - fMRI


  + No radiation used, no insertion

  + Spatial resolution = detail by MM

  - Strong magnets, no pacemakers, metal implants

  - Temporal resolution = 5 second time lag

  - Blood flow = can't see neuron activity so can't tell what is brain activity as activity when deceased

  - only correlation no cause
• EEG (electroencephalogram)


  - Electrodes attached to Ps scalp, measure electrical activity in neurons

  - Active areas have most electrical activity

  - Generate brain wave patterns, neuron frequency