Chapter 6

About

Biopsychology

Biopsychology is concerned with the ways in which biological factors influence mental processes, emotions, and behaviour. There are close links between psychology and biology, and biopsychology involves exploring those links in detail. In this section, we will focus on some of the key aspects of biopsychology.

What you need to know

The AS-level specification covers this topic as part of the Approaches to Psychology section, and you will only need to cover the first four subjects on the list below (Divisions of the nervous system, Structure and function of sensory, relay and motor neurons, Function of the endocrine system, and Fight or flight response). This will be examined in Paper 2 of the exam.

If you are studying A-level you will need to cover everything in this chapter. Biopsychology will be examined in Paper 2 of the exam.

  • Divisions of the nervous system: central and peripheral (somatic and autonomic) (see page 225 of the textbook)
  • Structure and function of sensory, relay and motor neurons (see page 228 of the textbook)
  • Function of the endocrine system: glands and hormones (see page 231 of the textbook)
  • Fight or flight response including the role of adrenaline (see page 233 of the textbook)
  • Localisation of function in the brain (see page 239 of the textbook)
  • Ways of studying the brain (see page 248 of the textbook)
  • Biological rhythms (see page 255 of the textbook)

Flashcards

Key Terms

Action potential - a brief electrical and chemical firing that allows nerve impulses to travel along an axon.

Adrenal cortex - the outermost part of the adrenal glands; it triggers the release of various hormones including cortisol during the stress response.

Adrenal glands - the endocrine glands that are located adjacent to (and covering) the upper part of the kidneys.

Adrenal medulla - the inner part of the adrenal glands; it is involved in the stress response by releasing the hormones adrenaline and noradrenaline.

Adrenaline - one of the hormones (along with noradrenaline) produced by the adrenal glands; it increases arousal by activating the sympathetic nervous system and reducing activity in the parasympathetic nervous system.

Adrenocorticotrophic hormone (ACTH) - a hormone secreted by the pituitary gland that stimulates the adrenal cortex and the secretion of various hormones including cortisol.

Androgens - sex hormones (e.g. testosterone) present in larger quantities in males than females.

Aphasia - a disorder of language caused by brain damage.

Autonomic nervous system - the part of the peripheral nervous system that controls the involuntary movement of non-skeletal muscles; it is divided into the sympathetic nervous system and the parasympathetic nervous system.

Axon - a part of the neuron that conducts nerve impulses away from the cell body or soma.

Axon terminals - these are found at the end of an axon; they allow electrical impulses to pass from one neuron to the next.

Belt region - this forms part of what was previously called secondary auditory cortex; it is connected to the parabelt region and primary auditory areas.

Broca’s aphasia - a form of language disorder involving damage to Broca’s area producing slow speech lacking fluency.

Central nervous system - the brain and spinal cord.

Circadian rhythms - biological rhythms that repeat every 24 hours approximately.

Congenital adrenal hyperplasia - an inherited disorder of the adrenal gland causing the levels of male sex hormones in foetuses of both sexes to be unusually high.

Cortisol - a hormone produced by the adrenal gland that elevates blood sugar and is important in digestion, especially at times of stress.

Dendrites - parts of the neuron that conduct nerve impulses towards the soma or cell body.

Dyscalculia - severe problems with arithmetic often due to brain damage.

Electroencephalogram (EEG) - the graphical representation of the brain’s electrical activity recorded by multiple scalp electrodes.

Endocrine system - a system consisting of a number of ductless glands located throughout the body; this system produces the body’s chemical messengers called

hormones.

Endogenous pacemakers - internal biological mechanisms that influence the sleep–wake cycle.

Entrainment - a process in which the internal clock or pacemaker is adjusted or changed by external zeitgebers.

Error-related negativity - a negative deflection in the ERP that occurs about 80–150 ms after an individual has made a behavioural error.

Event-related potentials (ERPs) - the pattern of electroencephalogram (EEG) activity obtained by averaging the brain responses to the same stimulus (or similar stimuli) presented repeatedly.

Exogenous zeitgebers - external events that partially determine biological rhythms.

Functional magnetic resonance imaging (fMRI) - a brain-imaging technique based on imaging blood oxygenation using an MRI scanner; it has very good spatial resolution and reasonable temporal resolution.

Glia - small cells in the nervous system that fulfil various functions (e.g. absorbing chemicals released by neurons; removing waste material from dead neurons).

Glucocorticoids - steroid hormones (e.g. cortisol) released from the adrenal cortex when the body is stressed.

Glucose - a form of sugar that is one of the main sources of energy for the brain.

Hemispherectomy - destruction of the whole of one hemisphere of the brain.

Hormones - chemical substances that are produced by one tissue before proceeding via the bloodstream to another tissue.

Hypothalamus - a small structure in the forebrain that is of relevance to eating, drinking, sexual activity, and temperature regulation.

Infradian rhythms - biological rhythms with a cycle of more than 1 day.

Ions - particles that are either positively or negatively charged.

Limbic system - this part of the forebrain consists of various structures (e.g. hypothalamus; hippocampus; amygdala) involved in emotion and motivation.

Melatonin - a hormone that influences the onset of sleep.

Motor neurons - neurons within the peripheral nervous system that send signals away from the central nervous system to the muscles and glands.

Neuron - cells that are specialised to conduct electrical impulses.

Neurotransmitters - chemicals that cross synapses and affect the receptors on adjacent neurons.

Oestrogens - sex hormones (e.g. oestradiol) present in larger quantities in females than males.

Oxytocin - this hormone promotes feelings of wellbeing by increasing sociability and reducing anxiety.

Parabelt region - this forms part of what used to be called secondary auditory cortex; it is connected to the belt region but not primary auditory areas.

Parasympathetic nervous system - the part of the autonomic nervous system that is involved in reducing arousal and conserving energy (e.g. by reducing heart rate).

Peripheral nervous system - it consists of all the nerve cells in the body not located within the central nervous system; it consists of the somatic nervous system and the autonomic nervous system.

Pheromones - chemicals released by one individual that have an effect on another individual.

Plasticity - changes in neural function and structure within the brain due to experience.

Premotor cortex - this brain area is used to prepare for movement and to link body actions with environmental objects.

Primary auditory cortex - the main area within the brain for receiving auditory input.

Primary motor cortex - this brain area is responsible for the production of voluntary body movements.

Proprioception - our knowledge concerning the location in space of our limbs.

Relay neurons - neurons within the central nervous system that receive input from sensory neurons or other relay neurons and send impulses to motor neurons or other relay neurons.

Resting potential - the condition in which the neuron is not firing when the electrical charge inside it is about –70mV.

Reticular formation - a part of the brain concerned with arousal, the regulation of sleep, and the control of breathing.

Seasonal affective disorder - a disorder that nearly always involves the sufferer experiencing severe depression during the winter months only.

Sensory neurons - neurons within the peripheral nervous system that respond to stimulation by sensory receptors and send signals towards the brain and spinal cord.

Sleep—wake cycle - the pattern of alternating sleep and wakefulness; in humans it consists of approximately 8 hours of nocturnal sleep and 16 hours of daytime wakefulness.

Soma - a cell body containing a nucleus.

Somatic nervous system - the part of the peripheral nervous system that controls the voluntary movements of skeletal muscles and hence the limbs.

Somatosensation - several perceptual processes based on information received from the skin and body.

Split brain patients - individuals in whom the direct links between the hemispheres have been severed.

Substantia nigra - a structure in the midbrain; damage to this structure can play a role in the onset of Parkinson’s disease.

Supplementary motor area (SMA) - this brain area is used in planning movement sequences (especially well-learned ones) and in co-ordinating movements involving both sides of the body.

Suprachiasmatic nucleus (SCN) - the structure within the hypothalamus that is involved in controlling various circadian rhythms including the sleep–wake cycle.

Sympathetic adrenal medullary (SAM) system - the source of the immediate stress response, also known as fight or flight, where the hypothalamus activates the autonomic nervous system, which in turn activates the adrenal medulla, producing the release of the stress hormones adrenaline and noradrenaline.

Sympathetic nervous system - the part of the autonomic nervous system that produces arousal and energy (e.g. an increased heart rate).

Synapses - the extremely small junctions between adjacent neurons where nerve impulses are relayed.

Thalamus - part of the forebrain and involved in several functions including wakefulness and sleep.

Ultradian rhythms - biological rhythms with a cycle of less than 1 day but more than 1 hour.

Vegetative state - a condition produced by brain damage in which there is limited wakefulness but an apparent lack of awareness and purposeful behaviour.

Wernicke’s aphasia - a form of language disorder involving damage to Wernicke’s area producing impaired language comprehension and fluent but often meaningless speech.

Weblinks

The Nervous System and Endocrine System

https://www.youtube.com/watch?v=z5tJe_zI1uw A simple, clear description of the neuron with a useful diagram.

https://www.youtube.com/watch?v=WhowH0kb7n0 A really clear and simple explanation of how a synapse works.

https://www.youtube.com/watch?v=ilA1V7sUXUA A series of slides with very clear descriptions and diagrams of the endocrine system and the nervous system.

http://www.g2conline.org/?gclid=CMXpzfLAlLMCFSTKtAodDVcAwA%20-%20Autism Genes to Cognition Online—a website about modern neuroscience, including a 3D model of the brain.

Fight or Flight response

http://www.health.harvard.edu/staying-healthy/understanding-the-stress-response An interesting article about the stress response, why it can be harmful, and how to moderate and control this.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3734071/ A full, peer-reviewed research paper on the effect of music on the stress response, angled to see if music could moderate the response. (NB This ties in with Research Methods: you could read it to see how a research article is structured, tied in with teaching Research Methods, and you could think about what music you might choose to relax to as a result of reading the findings in this paper.)

Ways of Studying the Brain

http://www.youtube.com/watch?v=FallWN1uYco&feature=fvwrel A demonstration of what to expect when you go for an MRI scan.

http://www.youtube.com/watch?v=PSoPsRPGjs4 A video demonstration of setting up an ERP electrode cap.

Discussion Points

Throughout AQA Psychology you may have noticed self-assessment questions in orange text in the margins. These are discussion points, designed to help you think about the key issues and research in the text, and to consider how you can apply psychology to real life. Although in many cases there is no correct answer to these questions, we have provided some example discussions that could arise from thinking about some of these points. They should also help you structure your thinking on the topic in question.

1. What are the drawbacks of using case studies to collect evidence?

Case studies tend to focus on one individual or a “unit” of individuals like a family or small community. However, there may be drawbacks to using this method to collect evidence. Case studies are not a method as such as they use a range of techniques to gain information. These may include questionnaires, interviews, diary studies, etc. Drawback of these techniques include:

  • Validity. How do we know that the person being studied is telling the truth?
  • Social desirability. The participant(s) may want to look good so will answer in such a way as to confirm that rather than what they truly believe or feel.
  • Demand characteristics. The participant(s) may somehow work out the aim of the study and respond according to that belief rather than how they truly feel.

There are additional drawbacks of using case studies. People may not want to continue being studied as they may get bored or find it too intrusive. Also, many case studies feature “unique” individuals making it somewhat difficult to generalise beyond the case study itself.

See also Eysenck’s AQA Psychology, pages 159, 206, and 367.

2. Can you think of some situations in which the fight or flight response may be activated?

One such situation could be bullying. A person has to make a decision to stand up to their aggressors or leave the situation for the better. People may feel all of the physiological reactions to this type of situation that appear when we are in the fight or flight mode: palpitations, sweating, etc.

Another situation might be when you enter your classroom thinking it is just another psychology lesson. A few minutes into the lesson everyone packs their belongings away and just sits there with a pen waiting for a test to begin. You thought the test was next week so were not prepared for this to happen. As above, you would begin to get the same physiological reactions of fight or flight.

Imagine also, a few weeks later, when you are about to give a presentation to the rest of the class for your A-Level Psychology. You had been working in pairs on the presentation but today your partner is absent so you have to do the presentation all by yourself! Yet again, the same basic physiological reactions to fight or flight would happen to you.

See also Eysenck’s AQA Psychology, pages 233–234.