Biopsychology

Question 1

CNS

Answer 1

Brain and spinal cord, it controls behaviour and regulation of the body’s physiological processes, to do this the brain receives info from the sensory receptor and sends messages to the muscles and glands of the body

Question 2

Brain

Answer 2

Cerebrum- largest part of the brain, four lobes and two hemispheres
Cerebellum- motor skills, balance and coordinating muscles to allow precise movements
Diencephalon- thalamus ( consciousness, sleep and alertness)+ hypothalamus (regulates body tempo, stress response and hunger and thirst)
Brain stem- regulates breathing and heart rate

Question 3

Spinal cord

Answer 3

Relay informs between the brain and the rest of the body, allows brain to monitor and regulate bodily processes e..g digestion, connected to different parts of the body by pairs of spinal nerves, connecting specific muscles and glands

Question 4

Peripheral nervous system

Answer 4

Consists of somatic and autonomic nervous system, responsible for transmitting messages to and from the CNS

Question 5

Somatic nervous system

Answer 5

Responsible for tracks siting information from sense organs to the CNS and transmitting in from from the CNS to the effectors (e.g. muscles and glands), control voluntary movement under conscious control, it has sensory and motor pathway, controls skeletal muscles. Controlled by the motor cortex

Question 6

Automatic nervous system

Answer 6

Has the sympathetic and parasympathetic nervous system and is responsible for transmitting info to and from internal bodily organs, it is involuntary, only has motor pathways and it controls smooth muscles and the internal organs and glands of the body. Controlled by the brain stem

Question 7

Sympathetic Nervous System (SNS)

Answer 7

works alongside the endocrine system to bring about physiological arousal in the fight or flight response. It is activated when a person is stressed. Heart rate and breathing increase, digestion stops, salivation reduces, pupils dilate, and the flow of blood is diverted from the surface on the skin (fight or flight response).

Question 8

The Parasympathetic Nervous System (PNS)

Answer 8

system works alongside the endocrine system to return the body to its resting state after fight or flight. Heart rate and breathing reduce, digestion starts, salivation increases, and pupils constrict. This is known as the rest and digest response.

Question 9

Structure of neurone

Answer 9

Neurons are specialised nerve cells that move electrical impulses to and from the Central Nervous System (CNS).
There are several parts to a neuron;
• Cell Body: Control centre of the neuron.
• Nucleus: Contains genetic material.
• Dendrites: Receives an electrical impulse (action potential) from other neurons or sensory receptors (e.g. eyes, ears, tongue and skin).
• Axon: A long fibre that carries the electrical impulse from the cell body to the axon terminal.
> Myelin Sheath: Insulating layer that protects the axon and speeds up the transmission of the electrical impulse.
> Schwann cells: Make up the myelin sheath.
• Nodes of Ranvier: Gaps in the myelin sheath. They speed up the electrical impulse along the axon.

Question 10

Sensory neurone

Answer 10

Sensory neurons are found in sensory receptors. They carry electrical impulses from the sensory receptors to the CNS (spinal cord and brain) via the Peripheral Nervous System (PNS). Sensory neurons convert information from sensory receptors into electrical impulses. When these impulses reach the brain they are converted into sensations, such as heat, pain etc. so that the body can react appropriately. Some sensory impulses terminate at the spinal cord. This allows reflexes to occur quickly without the delay of waiting for the brain to respond.

Question 11

Motor neurone

Answer 11

Motor neurons are located in the CNS but project their axons outside of the
CNS. They send electrical impulses via long axons to the glands and muscles so they can affect function. Glands and muscles are called effectors. When motor neurons are stimulated they release neurotransmitters that bind to the receptors on muscles to trigger a response, which leads to movement.

Question 12

Relay neurone

Answer 12

Relay neurons are found in the CNS. They connect sensory neurons to motor neurons so that they can communicate with one another. During a reflex arc (e.g. you put your hand on a hot hob) the relay neurons in the spinal cord are involved in an analysis of the sensation and decide how to respond (e.g. to lift your hand) without waiting for the brain to process the pain.

Question 13

Synaptic transmission

Answer 13

Neurones transmit electrical impulses (action potentials) between pre and post synaptic neurons, when it reaches the pre synaptic terminal it triggers the release of neurotransmitters from vesicles in a process of exocytosis, the neurotransmitters will diffuse across the syntactic cleft where if binds to specialised post synaptic receptor sites on the post synaptic membrane. It only takes a fraction of a second and the effects are terminated in a process called re-uptake. The neurotransmitter is taken back by the vesicles on the presynaptic neurone where they are stored for later release, the quicker it is taken back the shorter the effects

Question 14

Excitatory or inhibitory

Answer 14

Most are both, but GABA is purely inhibitory, excitatory neurotransmitters cause an electrical change in the membrane of the post-synaptic neuron resulting in an excitatory post synaptic potential, meaning that the post synaptic neurone in more likely to fire an impulses opposite for inhibitory

Question 15

Epsp and Ipsp

Answer 15

The likelihood that the neuron will fire an impulses opposite is determined by adding up the excitatory and the inhibitory synaptic input, the net result of this calculation is summation

Question 16

Direction of synaptic transmission

Answer 16

Information can only travel in ONE direction at a synapse. The vesicles containing neurotransmitters are ONLY present on the pre-synaptic membrane. The receptors for the neurotransmitters are ONLY present on the post-synaptic membrane. It is the binding of the neurotransmitter to the receptor which enables the information to be transmitted to the next neuron.
Diffusion of the neurotransmitters mean they can only go from high to low concentration, so can only travel from the pre-synaptic membrane to the post-synaptic membrane.

Question 17

Medication

Answer 17

Psychoactive drugs (medication that affects brain function to alter perception, mood or behaviour), such as SSRIs, work by affecting (increasing or inhibiting) the transmission of neurotransmitters across the synapse.
Some pain medications mimic the effects of inhibitory neurotransmitters.
Stimulation of postsynaptic receptors by an inhibitory neurotransmitter results in inhibition of the postsynaptic membrane. When an inhibitory neurotransmitter binds to the post-synaptic receptors it makes the post-synaptic neuron less likely to fire. Due to summation, if inhibitory neurotransmitters are higher than excitatory neurotransmitters they can inhibit an action potential from occurring. Therefore, pain medications would decrease the overall activity and reducing brain activity may lead to less pain.

Question 18

Endocrine system

Answer 18

It provides a chemical system of communication in the body via the blood stream, they produce and secrete hormones into the bloodstream which are required to regulate many bodily functions, the major ones are pituitary gland and the adrenal glands. Each gland produces different hormones which regulate activity of organs/tissues in the body, they only affect limited number of cells (target cells). Because they have the receptor for that hormone, when enough receptor sites are stimulated by that hormone there is a physiological reaction

Question 19

Pituitary gland

Answer 19

Located in the brain, controlled by the hypothalamus, controls the release of hormones from all other glands, e.g. it produces ACTH which is involved in the stress response by stimulating the production and release of cortisol from the adrenal glands (anterior pituitary gland), releases hormone OxyContin which is crucial for mother/infant bonding (posterior pituitary gland)

Question 20

Adrenal glands

Answer 20

We have 2, situated on top of each kidney, each one made up of two distinct parts, adrenal gland produces adrenaline which triggers fight or flight response

Question 21

Adrenal cortex

Answer 21

Outer section of the adrenal gland, produces hormone cortisol produced in high amount when someone is experiencing chronic stress, also responsible for the cardiovascular system e.g. increases bo and causes blood vessels to constrict

Question 22

Adrenal Medulla

Answer 22

Inner section of the adrenal glands, produces adrenaline

Question 23

Sympathomedullary pathway

Answer 23

During stressful situations the body’s fight or flight response is activated by the sympathetic branch of the autonomic nervous system, the sympathetic nervous system is trigger by the hypothalamus, it then stimulates the adrenal medulla to release adrenaline in the blood stream

Question 24

Evaluation of fight or flight response

Answer 24

+ makes sense from evolutionary psychology- explains how individuals survived threats
+studies show that adrenaline is essential for preparing the body in stressful situation, a person with a malfunctioning adrenal gland does not have normal, fight or flight response
-freeze
-women are more likely to tend and befriend- hormone oxycotocin

Question 25

Localisation of function

Answer 25

Principle that functions have specific locations within the brain, the hemisphere of the cerebrum represent the opposite side of the body (contralateral organisation)

Question 26

Motor cortex

Answer 26

Responsible for voluntary movements, located in the frontal lobe of both hemisphere, different parts of the motor cortex control different parts of the body. Damage to this area can cause loss of muscle function in one or both sides of the body depending on the hempishere

Question 27

Somatosensory cortex

Answer 27

Responsible for processing sensations such as pain and pressure, located in the parietal lobe of both hemisphere

Question 28

Visual cortex

Answer 28

Process info such as colour and shape, located in the occipital lobe of both hemisphere, visual processing starts in the retina where light enters and strikes the photoreceptors, transmitted to the brain by the optic nerve

Question 29

Auditory cortex

Answer 29

Process info such as pitch and volume, lies in the temporal lobe in both hemisphere of the brain, begins in the cochlea in the inner ear, where sound waves are converted to nerve impulses which travel via the auditory nerve to the auditory cortex

Question 30

Broca’s area

Answer 30

Lesion to the left hemisphere of the frontal lobe, damage to the Broca’s area causes expressive aphasia, the disorder affects language production but not understanding

Question 31

Wernicke’s area

Answer 31

Left hemisphere of the frontal lobe, could speak but not understand language, it is responsible for processing of spoken language, both are connected by a neural loop, causes receptive aphasia

Question 32

Evaluation

Answer 32

• Some functions are more localised than others. Motor and somatosensory functions are highly localised to specific areas of the cortex. However, higher functions (e.g. personality and consciousness) are much more widely distributed Functions such as language are too complex to be assigned to just one area and instead involve networks of brain regions. Although some components of language, such as speech production, may be localised (Broca’s Area.
• Equipoteniality theory (Lashley, 1930) holds that higher mental functions are not localised. The theory also claims that intact areas of the cortex take over responsibility for a specific cognitive function following injury to the area normally responsible.
• Dronkers et al. (2007) re-examined the preserved brains of two of Broca’s patients. MRI scans revealed that several areas of the brain had been damaged.
  Lesions to the Broca’s Area cause temporary speech disruption they do not usually result in severe disruption of language. Language is a more widely distributed (and less localised) skill than originally thought.
• It may be that how brain areas communicate with each other is more important than specific brain regions. Dejerine (1892) reported a patient who could not read because of damage between the visual cortex and Wernicke’s area.
• Bavelier et al. (1997) found that there are individual differences in which brain areas are responsible for certain functions. They found that different brain areas are activated when a person is engaged in silent reading. They observed activity in the right temporal lobe, left frontal lobe and occipital lobe. This means that the function of silent reading does not have a specific location within the brain.

Question 33

Hemispheric lateralisation

Answer 33

Certain functions are governed by one side of the brain
Language centres are lateralised,aided to the left hemisphere, the right hemisphere is dominant for visual-spatial funcgkon and facial recognition, both are connected by a bundle of nerve fibres known as cropus callosum allowing for info to be communicated between the two hemisphere