Biopsychology Key Terms

• Nervous system


  Consists of the central nervous system and the peripheral system. Communicates using electrical signals
• Central Nervous System (CNS)


  Consists of the brain and spinal cord and is the origin of all complex commands and decisions
• Peripheral Nervous System (PNS)


  Sends information to the CNS from the outside world, and transmits messages from the CNS to muscles and glands in the body.
• Somatic Nervous System (SNS)


  Transmits information from receptor cells in the sense organs to the CNS. It also receives information from the CNS that directs muscles to act.
• Autonomic Nervous System (ANS)


  Transmits information to and from internal bodily organs. It is 'autonomic' as the system operates involuntarily. It has two main divisions:

  - the sympathetic nervous system

  - the parasympathetic nervous system
• Endocrine system


  One of the body's major information systems that instructs glands to release hormones directly into the bloodstream. These hormones are carried towards target organs. Communicates via chemical
• Gland


  An organ in the body that synthesis substances such as hormones
• Hormones


  A biochemical substances that circulates in the blood but only affects target organs. They are produced in large quantities but disappear quickly
• Adrenaline


  A hormone produced by the adrenal glands which is part of the human body's immediate stress response system. Adrenaline has a strong effect on the cells of the cardiovascular system - stimulating the heart rate, contracting blood vessels and dilating air passages.
• Fight or flight response

  Way an animal responds when stressed. The body becomes physiologically aroused in readiness to fight an aggressor or in some cases flee
• Neuron


  The basic building blocks of the nervous system, neurones are nerve cells that process and transmit messages through electrical and chemical signals
• Sensory neuron


  These carry messages from the PNS to the CNS. They have long dendrites and short axons
• Relay neuron


  These connect the sensory neurons to the motor or other relay neurons. They have short dendrites and short axons.
• Motor neuron


  These connect the CNS to effectors such as muscles and glands. They have short dendrites and short axons
• Synaptic transmission


  The process by which neighbouring neurons communicate with each other by sending chemical messages across the gap (the synapse) that separates them.
• Neurotransmitters


  brain chemicals that carry information from the axon of a sending neuron to the dendrites of a receiving neuron
• Excitation


  increases the neurons positive charge and making it more likely the postsynaptic neuron will fire and pass on the electrical impulse
• Inhibition


  When a neurotransmitter, such as serotonin, makes the charge of the postsynaptic neuron more negative. This decreases the likelihood that the neuron will fire and pass on the electrical impulse.
• Localisation of brain function


  The theory that different areas of the brain are responsible for different behaviours, processes or activities.
• Visual cortex


  A part of the occipital lobe that receives and processes visual information
• Somatosensory area


  An area of the parietal lobe that processes sensory information such as touch
• Motor area


  A region of the frontal lobe involved in regulating movement
• Broca's area


  An area of the frontal lobe in the left hemisphere, responsible for speech production
• Wernicke's area


  An area of the temporal lobe in the left hemisphere responsible for language comprehension
• Hemispheric lateralisation


  The idea that the two halves of the brain are functionally different and that certain mental processes and behaviours are mainly controlled by one hemisphere rather than the other.
• Plasticity


  Describes the brain's tendency to change and adapt as a result of experience and new learning. This generally involves the growth of new connections
• fMRI


  A method used to measure brain activity while a person performs a task. fMRI detects radio waves from changing magnetic fields. This enables researchers to detect regions which are rich in oxygen
• EEG


  A record of the tiny electrical impulses produced by the brain's activity. By measuring characteristics wave patterns, the EEG can help diagnose certain conditions of the brain
• ERP


  The electro physiological response of the brain to a specific sensory, cognitive, or motor event can be isolated through statistical analysis of EEG data
• Post-Mortem


  The brain is analysed after death to determine whether certain observed behaviours during the person's lifetime can be linked to structural abnormalities in the brain
• Circadian rhythm


  Biological rhythms, subject to a 24 hour cycle, which regulate a number of body processes such as the sleep/wake cycle and changes in core boy temperature
• Infradian rhythm


  A type of biological rhythm with a frequency of less than one cycle in 24 hours, such as menstruation and seasonal affective disorder.
• Ultradian rhythm


  A type of biological rhythm with a frequency of more than one cycle in 24 hours, such as the stages of sleep.
• Auditory area


  Located in the temporal lobe and concerned with the analysis of speech-based information
• Functional recovery


  A form of plasticity. Following damage through trauma, the brain's ability to redistribute or transfer functions usually performed by a damaged area to other, undamaged areas.
• Biological rhythms


  Distinct patterns of changes in body activity that conform to cyclical time periods. Biological rhythms are influenced by internal body clocks (endogenous pacemakers) as well as external changes to the environment (exogenous zeitgebers).