Biopsychology - Paper 2

What are the two main divisions of the nervous system?

Central Nervous System (CNS) - brain and spinal cord

Peripheral Nervous System (PNS) - sends and receives information to and from the CNS.

What are the two divisions of the peripheral nervous system?

Somatic Nervous System - transmits information from sense organs to the CNS

Autonomic Nervous System - controls vital bodily functions.

What are the two branches of the autonomic nervous system and their functions?

Sympathetic Nervous System - prepares body for fight or flight

Parasympathetic Nervous System - restores normal physiological functioning after stress.

What are the main parts of a neuron and their functions?

Dendrites - receive signals; Cell body (soma) - contains nucleus; Axon - carries impulses; Myelin sheath - insulates axon; Nodes of Ranvier - facilitate rapid conduction; Axon terminals - transmit signals.

What is the role of a sensory neuron?

Carries messages from the PNS to the CNS.

What is the role of a relay neuron?

Connects sensory neurons to motor neurons; found in the brain and spinal cord.

What is the role of a motor neuron?

Sends messages from the CNS to muscles and glands to produce movement or secretion.

Outline the process of synaptic transmission.

1️⃣ Electrical impulse travels down the pre-synaptic neuron. 2️⃣ Impulse triggers vesicles with neurotransmitters to move. 3️⃣ Neurotransmitters diffuse across the synapse. 4️⃣ Initiates a new impulse in the post-synaptic neuron.

What is a neurotransmitter?

A chemical released by a neuron that affects another neuron's activity.

What is serotonin and its effect?

Involved in mood, sleep, and appetite; too little is linked to depression and OCD.

What is dopamine and its effect?

Involved in movement and pleasure; too much is linked to schizophrenia.

What is meant by excitation?

Excitatory postsynaptic potential (EPSP) makes the post-synaptic neuron more likely to fire.

What is meant by inhibition?

Inhibitory postsynaptic potential (IPSP) makes the post-synaptic neuron less likely to fire.

What is summation?

The combined effect of EPSPs and IPSPs determines whether the neuron fires.

What is the endocrine system?

A network of glands that regulate growth, metabolism, and sexual development by secreting hormones.

What are glands and hormones?

Glands - organs that produce hormones; Hormones - chemical messengers that regulate various functions.

Outline the fight or flight response to stress.

1️⃣ Hypothalamus detects stressor. 2️⃣ Pituitary gland releases ACTH. 3️⃣ Adrenal glands activated; adrenaline released. 4️⃣ Autonomic and sympathetic nervous systems stimulated.

What is meant by localisation of function?

The idea that specific functions are controlled by particular areas of the brain.

What are the four main cortical areas and their functions?

Motor cortex - voluntary movement; Somatosensory cortex - processes sensory info; Visual cortex - processes visual info; Auditory cortex - processes sound.

What are Broca's and Wernicke's areas responsible for?

Broca's area - speech production; Wernicke's area - language comprehension.

What evidence supports localisation?

Case studies: Phineas Gage, Broca's patient 'Tan', Wernicke's patients, Corporal G.M., Alan Burgess.

What are 3 limitations of localisation of function?

1. Equipotentiality theory; 2. Brain plasticity; 3. Importance of communication between regions.

What are 3 strengths of localisation of function?

1. Brain-scan evidence; 2. Case-study support; 3. Neurological evidence.

What is hemispheric lateralisation?

The idea that each hemisphere of the brain has specialised functions.

What is contralateral organisation?

Each hemisphere controls the opposite side of the body — e.g. the left hemisphere controls the right hand.

What connects the two hemispheres?

The corpus callosum, a bundle of nerve fibres allowing communication between hemispheres.

What happens when the corpus callosum is severed?

The hemispheres cannot communicate; information processed in one hemisphere cannot be transferred to the other.

What was the aim of Sperry & Gazzaniga's study?

To investigate how the two hemispheres function independently when the corpus callosum is severed.

What was the procedure in Sperry & Gazzaniga's study?

Split-brain patients fixated on a dot while images were flashed for 1/10 second to either visual field. Responses were made with the hand controlled by the opposite hemisphere.

What were the visual-field findings in Sperry & Gazzaniga's study?

Image to right visual field → left hemisphere → patient could describe it verbally. Image to left visual field → right hemisphere → patient could not describe it verbally but could identify it by touch.

What were the tactile-test findings in Sperry & Gazzaniga's study?

Object in left hand → right hemisphere → patient could identify by touch but not name it. Object in right hand → left hemisphere → patient could describe it verbally.

What were the drawing-task findings in Sperry & Gazzaniga's study?

Left hand (right hemisphere) consistently produced better drawings → right hemisphere superior for visual-motor tasks.

What did Gazzaniga's artwork test show?

Facial recognition = right hemisphere; speech & language = left hemisphere.

What are (3 strengths of split-brain research)?

• Controlled lab experiments → high internal validity. • Objective measurements → scientific reliability. • Provided clear evidence for hemispheric specialisation.

What are (3 limitations of split-brain research)?

• Small sample size → limited generalisability. • Participants all had epilepsy → may not represent normal brains. • Artificial tasks → low ecological validity.

What did Kimura (1967) find using dichotic listening tests?

Participants heard more digits presented to the right ear → language lateralised to the left hemisphere.

What did Bauer et al (2014) find using the sodium amytal test?

When the left hemisphere was anesthetised, patients became mute or made speech errors → left hemisphere key for language.

What did Danelli et al (2013) find about patient EB?

After left-hemisphere removal, EB regained language ability → right hemisphere can take over language functions → plasticity evidence.

What are (3 strengths of hemispheric lateralisation)?

• Large volume of research (Sperry & Gazzaniga → replicated findings). • Objective lab methods → scientific credibility. • Case studies (Kim Peek) show bilateral language centres → deepens understanding.

What are (3 limitations of hemispheric lateralisation)?

• Small, atypical samples → limited generalisability. • Artificial tasks → may not reflect everyday functioning. • Individual differences → bilateral or variable lateralisation (e.g. Peek).

What is neuroplasticity?

The brain's ability to physically and functionally change as a result of experience and learning.

What is functional recovery?

The brain's ability to transfer functions from damaged areas to undamaged ones after trauma.

What did Maguire et al (2000) find?

London taxi drivers had larger posterior hippocampi than controls → spatial navigation training increases grey matter.

What did Draganski et al find?

Medical students showed increased grey matter after exam preparation → learning changes brain structure.

What did Kuhn et al (2014) find?

Playing Super Mario 30 min/day for 2 months increased grey matter in cortex, hippocampus, cerebellum → video-game training enhances spatial navigation, working memory, motor performance.

What did Boyke et al (2008) find?

60-year-olds learning juggling showed increased grey matter in visual cortex → changes reversed when practice stopped.

What did Davidson et al (2004) find?

Tibetan monks showed greater gamma-wave activation than non-meditators → meditation can produce permanent brain changes.

What did the case of Jodie show?

After right-hemisphere removal at age 3, left hemisphere took over functions → new neural connections and blood vessels formed → able to move left side → functional recovery evidence.

What are (3 strengths of neuroplasticity research)?

• Scientific brain-scan evidence (Maguire, Draganski, Kuhn). • Practical applications → rehabilitation after injury. • Demonstrates lifelong brain adaptability.

What are (3 limitations of neuroplasticity research)?

• Individual differences → age and experience affect recovery. • Correlational evidence → causality uncertain. • Plasticity may lead to maladaptive changes (e.g. phantom-limb pain).

What is cognitive neuroscience?

Cognitive neuroscience is the scientific study of the brain, neurological structures, mechanisms, processes and chemistry responsible for cognitive (mental) processes. It uses brain-scanning techniques to locate the physical basis of cognitive processes in the brain.

What is functional Magnetic Resonance Imaging (fMRI)?

fMRI is a brain-scanning technique that uses magnetic fields and radio waves to monitor blood flow in the brain. It measures changes in the energy released by haemoglobin (oxygen consumption), which reflects brain activity.

How does fMRI identify active areas of the brain?

fMRI detects increased blood flow and oxygenation in brain regions. Activity during a specific task is compared with activity during a baseline task, allowing active regions to be identified.

What does an fMRI scan produce?

A moving, detailed 3D image of the brain that shows both brain structure and brain function.

What are 3 strengths of fMRI?

• Produces detailed 3D images of the brain. • Measures dynamic brain activity rather than just brain structure. • Non-invasive and does not expose participants to radiation.

What are 3 limitations of fMRI?

• Very expensive to buy and operate. • Interpretation of results is complex and can be influenced by the baseline task used. • Has relatively poor temporal resolution because blood flow changes occur after neural activity.

Why does fMRI have poor temporal resolution?

There is approximately a 5-second delay between neural activity occurring and the blood-flow changes detected by the scanner.

Why is fMRI considered more useful than a standard MRI scan?

MRI only shows brain structure, whereas fMRI shows both brain structure and brain function by identifying which brain areas are active during cognitive tasks.

Why can the high cost of fMRI reduce the validity of research?

The expense of fMRI often leads to smaller sample sizes, making findings less representative and reducing validity.

What is electroencephalography (EEG)?

EEG is a technique that records electrical activity in the brain using electrodes placed on the scalp.

How does an EEG work?

Electrodes attached to the scalp detect electrical impulses produced by neurons directly beneath the electrodes.

What does an EEG measure?

EEG measures the electrical activity generated by neurons in the brain.

What are 3 strengths of EEGs?

• Directly measure electrical brain activity. • Have very high temporal resolution measured in milliseconds. • Useful for diagnosing disorders such as epilepsy and brain tumours.

What are 3 limitations of EEGs?

• Poor spatial resolution. • Cannot accurately locate the exact source of brain activity. • Neural activity is often generalised to broad brain regions rather than precise locations.

What is meant by EEGs having high temporal resolution?

EEGs can detect changes in brain activity within milliseconds, making them very accurate for determining when brain activity occurs.

What is meant by EEGs having poor spatial resolution?

EEGs cannot accurately pinpoint the exact location of activity within the brain.

What is an Event-Related Potential (ERP)?

An ERP is a physiological response in the brain to a specific sensory, cognitive or motor stimulus that is identified through statistical analysis of EEG recordings.

How are ERPs obtained?

ERPs are obtained by recording EEG activity and using statistical analysis to isolate the brain's response to a particular stimulus.

What do ERPs measure?

ERPs measure the brain's response to specific sensory, cognitive or motor stimuli.

What are 3 strengths of ERPs?

• Measure responses to specific stimuli. • Have very high temporal resolution. • Allow researchers to investigate cognitive processes linked to particular events.

What are 3 limitations of ERPs?

• Poor spatial resolution. • Difficult to accurately identify the location of activity within the brain. • Susceptible to extraneous variables that may affect recordings.

What is the P300 ERP component associated with?

The P300 ERP component is associated with working memory and attentional processing.

How do EEGs and ERPs compare with fMRI for temporal resolution?

EEGs and ERPs have much better temporal resolution because they measure brain activity in milliseconds, whereas fMRI relies on slower blood-flow changes.

How do EEGs and ERPs compare with fMRI for spatial resolution?

EEGs and ERPs have poorer spatial resolution because they cannot accurately pinpoint where activity is occurring, whereas fMRI can localise activity more precisely.

How do EEGs and ERPs compare with fMRI in terms of cost?

EEGs and ERPs are significantly cheaper than fMRI and can therefore be used more widely in research.

What is a post-mortem examination (PME)?

A post-mortem examination involves studying and dissecting the brain after death to identify abnormalities and link them to behaviour or psychological disorders.

What are 3 strengths of post-mortem examinations?

• Allow detailed examination of brain structures. • Can identify abnormalities associated with behaviour and disorders. • Have contributed to important discoveries about brain localisation, such as Broca's and Wernicke's areas.

What are 4 limitations of post-mortem examinations?

• Findings cannot benefit the deceased individual. • Often involve very small sample sizes. • Brain changes may occur during and after death, reducing validity. • Ethical concerns may arise regarding consent and dissection.

How did post-mortem examinations contribute to our understanding of language localisation?

They helped identify Broca's area as responsible for speech production and Wernicke's area as responsible for language comprehension.

Why may post-mortem examinations have low validity?

Small sample sizes and neuronal changes that occur during and after death may reduce the accuracy of findings.

What are lesion studies?

Lesion studies investigate how damage or abnormalities in specific areas of the brain affect behaviour, cognition or psychological disorders.

What evidence from lesion studies has been found in schizophrenia?

Some people with schizophrenia have been found to have enlarged ventricles in the brain.

Why can lesion studies not establish cause and effect?

They are correlational. An abnormality may be associated with a disorder, but it does not prove the abnormality caused the disorder. The abnormality could be a consequence rather than a cause.

What is the difference between MRI and fMRI?

MRI provides images of brain structure, whereas fMRI provides information about both brain structure and brain activity.

How does fMRI compare with MRI and post-mortem examinations?

fMRI measures ongoing, dynamic brain activity, whereas MRI and post-mortem examinations mainly provide information about brain structure.

What is an advantage of studying brain activity directly in humans using techniques such as fMRI, EEG and ERP?

Findings are more directly relevant to human behaviour and avoid some of the validity and ethical issues involved in generalising from animal studies.

What comparison-based evaluation points are useful in AQA essays on ways of studying the brain?

• Comparing temporal resolution between techniques. • Comparing spatial resolution between techniques. • Comparing the ability to measure structure versus function. • Comparing cost and accessibility. • Comparing validity and usefulness for research. • Comparing levels of invasiveness and ethical issues.

What are the four basic EEG wave patterns?

Alpha waves (awake and relaxed), Beta waves (physiologically aroused or REM sleep), Theta waves (deep sleep), and Delta waves (deep sleep).

What is the difference between sensory and cognitive ERPs?

Sensory ERPs occur within the first 100ms and reflect physical characteristics of a stimulus; cognitive ERPs occur after 100ms and reflect stimulus evaluation and higher processing.