Biopsychology

Specification The divisions of the nervous system: central and peripheral (somatic and autonomic). The structure and function of sensory, relay and motor neurons. The process of synaptic transmission, including reference to neurotransmitters, excitation and inhibition. The function of the endocrine system: glands and hormones. The fight or flight response including the role of adrenaline. Localisation of function in the brain and hemispheric lateralisation: motor, somatosensory, visual, auditory and language centres; Broca’s and Wernicke’s areas, split brain research. Plasticity and functional recovery of the brain after trauma. Ways of studying the brain: scanning techniques, including functional magnetic resonance imaging (fMRI); electroencephalogram (EEGs) and event-related potentials (ERPs); post-mortem examinations. Biological rhythms: circadian, infradian and ultradian and the difference between these rhythms. The effect of endogenous pacemakers and exogenous zeitgebers on the sleep/wake cycle.

Central nervous system Spinal cord Brain Peripheral nervous system Key Terms Nervous system Central nervous system Spinal cord Brain Peripheral nervous system Somatic nervous system Autonomic nervous system Neuron Sensory neurons Motor neurons Sympathetic nervous system Parasympathetic nervous system

The nervous system Made up of billions of neurons A neuron is a cell that makes up the nervous system They conduct electrical impulses Biopsychologists assume that behaviour and experiences are caused by activity in the nervous system The nervous system is a specialised network of cells in the human body and is our primary internal communication system It has two main functions: To collect, process and respond to information in the environment To co-ordinate the working of different organs and cells

The major sub-divisions of the human nervous system

CNS Brain and spinal cord

The central nervous system (CNS) The CNS is made up of the brain and the spinal cord The brain is the centre of all conscious awareness. The brain’s outer layer, the cerebral cortex, is highly developed in humans The brain is divided in two hemispheres The spinal cord is an extension of the brain and transfers messages to and from the brain, and the rest of the body. It is responsible for reflex actions that do not involve the brain e.g jumping out of your chair if you sit on a drawing pin. The CNS passes messages to and from the brain and connects nerves to the PNS

The brain Section 1: (The Brain) The Cerebral Cortex, which is involved in a variety of higher cognitive (conscious thought), emotional, sensory, and motor (movement) functions is more developed in humans than any other animal. It is what we see when we picture a human brain, the gray matter with a multitude of folds making up the outer layer of the brain. The brain is divided into two symmetrical hemispheres: left (language, the ‘rational’ half of the brain, associated with analytical thinking and logical abilities) and right (more involved with musical and artistic abilities). These are further divided up into four distinct lobes, which you will learn more about later. Under the cerebral cortex is the area of the brain which is more primitive and are concerned with vital functioning and instinctive behaviour.

Brain Four main lobes: frontal lobe higher-order functions, including planning, abstract reasoning and logic parietal lobe integrates information from the different senses and therefore plays an important role in spatial navigation temporal lobe processes auditory information occipital lobe processes visual information Brain stem Connects the brain and spinal cord and controls involuntary processes, including our heartbeat, breathing and consciousness.

The spinal cord The spinal cord is a white bundle of nerves, which runs from your brain down a canal in your backbone. It's roughly 40cm long and about as wide as your thumb for most of its length. Like the brain, your spinal cord is part of your central nervous system. Its main function is to relay information about what's happening inside and outside your body to and from your brain. It is also involved in reflex actions, such as the startle response.  

Complete the section A exam questions on the CNS Test yourself… Complete the section A exam questions on the CNS

PNS

The peripheral nervous system (PNS) The PNS transmits messages via millions of neurons (nerve cells), to and from the central nervous system The PNS is further sub-divided into: the somatic nervous system (SNS) the autonomic nervous system (ANS)

The somatic nervous system (1) The Somatic Nervous System is part of the PNS that is concerned with the interaction of the outside world. Consists of 31 spinal nerves It controls the voluntary movement of skeletal muscles. It also consists of the nerves that carry messages from the eyes, ears, skeletal muscles and the skin to give the CNS experience of its environment. Sensory – information from the senses to the CNS Motor – Brain to the skeletal muscles for motor activity

The Autonomic Nervous System (1) Is the part of the PNS that controls involuntary movement from non-skeletal muscles, for example, the ‘smooth muscles’ that control the intestines, bladder, pupil size etc. and the cardiac muscle (the heart). It governs vital functions in the body such as breathing, heart rate, digestion, sexual arousal and stress responses The ANS is spilt into two further systems: the sympathetic and parasympathetic systems.

The two main divisions of the ANS The two main divisions of the autonomic nervous system are: The sympathetic nervous system The parasympathetic nervous system Their actions are mostly antagonistic - that is they usefully work in opposition to each other

The two main divisions of the ANS Section 1a: The Sympathetic Nervous System Is activated in situations requiring arousal and energy. When we feel threatened or under stress, the sympathetic branch of the ANS is activated which starts the instinctive reaction of ‘fight or flight’, aiding survival (you have more detail later). It produces increased heart and respiratory (breathing) rate, increasing blood flow to the muscles and pupil dilation (bigger pupils)   Section 1b: the Parasympathetic Nervous System This is activated soon after the threat of danger has passed. This has the opposite effect of the Sympathetic Nervous System and allows for the body to return to homeostasis (balance). Here the person’s heart and respiratory rate decrease to normal levels and blood flow decreases. The pupils return to normal size. This system is vital for the individual to conserve energy and not to become exhausted

The opposing actions of the sympathetic and the parasympathetic nervous system Organ Sympathetic nervous system Parasympathetic nervous system Gut Slows digestion Increases digestion Salivary glands Inhibits saliva production Increases saliva production Heart Increases heart rate Decreases heart rate Liver Stimulates glucose production Stimulates bile production Bladder Stimulates urination (relaxes the bladder) Inhibits urination (contracting bladder) Eye Dilates pupils Constricts pupils Lungs Dilates bronchi Constricts bronchi

Complete “Are you Sympathetic (or Parasympathetic)? Generally creates a physiological calm Generally arouses the body prepares the body to use energy for fight or flight maintains and conserves body energy and functions Complete “Are you Sympathetic (or Parasympathetic)?

1. Part of the nervous system that transmits information to and from the central nervous system. 2. Provides the biological basis of psychological experience and is made up of billions of nerve cells. The nervous system 3. Part of the central nervous system that receives and transmits information to and from the brain. peripheral Spinal cord 6 4. Part of the central nervous system that maintain life, involved in higher functions and psychological processes. The Brain 5. There are thought to be 100 billion of these in the brain. They receive and transmit information in the nervous system. The CNS Neurons

1. This is part of the autonomic nervous system that increases bodily arousal. It is activated in the presence of a perceived stressor. 2. This is part of the autonomic nervous system that decreases and maintains physiological arousal and bodily activities. Sympathetic 3. The is part of the peripheral nervous system that transmits information from and to our internal organs to sustain life. It is divided into the sympathetic and parasympathetic nervous system. Parasympathetic 4. This is part of the peripheral nervous system that carries sensory and motor signals to the CNS. Autonomic Somatic 5. These are neurons found in the somatic nervous system. They transmit information from the senses and transmit this to the CNS. Also known as Afferent neurons 6. These are neurons found in the somatic and autonomic nervous system. They carry information from the CNS to organs, glands and muscles. motor sensory

Test yourself…. Complete the section B exam questions on the PNS Complete the hand out on the ANS

Draw out the full diagram on page 3 of your packs Are you ready…. Draw out the full diagram on page 3 of your packs

The major sub-divisions of the human nervous system

Exam practice 1. Briefly distinguish between the central nervous system and the peripheral nervous system (2 marks) 2. Jenny has heard a loud bang and experienced the startled response. Which part of the nervous system is responsible for this and describe one bodily action in relation to the noise (1 + 2 marks) 3. Outline the main functions of the central nervous system (3 marks) 4. Outline the organisation of the autonomic nervous system (4) 5. Outline the divisions of the nervous system (6)

1) Briefly distinguish between the central nervous system and the peripheral nervous system (2 marks) The central nervous system (CNS) consists of the brain and the spinal cord, whereas the peripheral nervous system (PNS) consists of the somatic and autonomic nervous system. The CNS is responsible for all conscious awareness and experience as well as some reflex actions, whereas the PNS is responsible for sending messages to and from the CNS to organs and muscles and the involuntary fight or flight response.

2) Jenny has heard a loud bang and experienced the startled response 2) Jenny has heard a loud bang and experienced the startled response. Which part of the nervous system is responsible for this and describe one bodily action in relation to the noise (1 + 2 marks) The sympathetic nervous system (1 mark). One bodily action is that her heart rate increases (1 mark) to increase the flow of blood to the muscles (1 mark)

3) Outline the main functions of the central nervous system (4 marks) The Central Nervous System consists of the brain and the spinal cord. The brain is involved in a variety of higher cognitive, emotional, sensory, and motor (movement) functions. The brain is divided into two symmetrical hemispheres: the left is linked to language and is considered the ‘rational’ half of the brain, associated with analytical thinking and logical abilities. The right hemisphere is more involved with musical and artistic abilities. The brain also contains many structures responsible for regulating actions which keep us alive. The main function of the spinal cord is to relay information about what's happening inside and outside your body to and from your brain. It is also involved in reflex actions, such as the startle response.

4. Outline the organisation of the autonomic nervous system (4) The autonomic nervous system is organised into the sympathetic nervous system and the parasympathetic nervous system (1). The sympathetic nervous system is involved in bodily arousal and is stimulated when we face a stressor (1) This causes the heart rate to increase and releases stored energy. This response is known as fight or flight(1). The parasympathetic nervous system is activated when the stressor has passed and restores the body to a resting state, known as rest and digest. (1)

Outline the division of the nervous system (6) The nervous system is split into the central nervous system (CNS) and the peripheral nervous system (PNS). The central nervous system is divided into the brain, which contains billions of nerve cells and the spinal cord which links the brain to the peripheral nervous system. The PNS is split into the somatic nervous system (SNS) and the autonomic nervous system (ANS). The somatic nervous system consists of sensory neurons which transmit information from the sensory receptors in the body to the CNS. Motor neurons transmit information from the CNS to voluntary muscles for movement. The ANS works automatically and is not under voluntary control. It is split into the sympathetic nervous system, which is responsible for the fight or flight response and the parasympathetic nervous system which returns our body back to calm after the stress response, otherwise known as rest and digest.

Match up – each = ½ a mark Total - 3 2f 3d 4b 5a 6e

Plenary: You will be given a card by your teacher who is the nervous system. Read it through it carefully and try to work out which bit of the nervous system it is referring to. Don't discuss and don't look at notes. The classroom has now been split in half- cns and pns. You have one minute to decide which half of the nervous system you belong in and get to that side. Does your side agree you should be there? Now the tables in your half have been named either brain, spinal cord, somatic, autonomic, sympathetic and parasympathetic. Where do you belong? Go to your table and share your card with your group. Are you in the right place?