Brain and Neuropsychology

nervous system

The network of nerve cells and fibers that transmits nerve impulses between parts of the body.

Central nervous system

Consists of the brain and spinal cord

peripheral nervous system

The sensory and motor neurons that connect the central nervous system to the rest of the body. Composed of the somatic nervous system and the autonomic nervous system.

Somatic nervous system

The division of the peripheral nervous system that controls the body's skeletal muscles. Voluntary movement.

Autonomic Nervous System

The division of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms.

Sympathetic division of the ANS

Involved in preparing the body for behavior, particularly in response to stress, by activating the organs and the glands in the endocrine system.

Parasympathetic division of the ANS

Calm the body by slowing the heart and breathing and by allowing the body to recover from the activities that the sympathetic system causes

Homeostasis

A tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level

Fight or Flight Response

Activation of the sympathetic division of the autonomic nervous system, allowing access to energy reserves and heightened sensory capacity so that we might fight off a given threat or run away to safety

Adrenaline

A hormone released into the bloodstream in response to physical or mental stress

Adrenal Glands

A pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.

Cardiovascular system

heart and blood vessels

Hypothalamus

A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.

Physiological changes/arousal

Related to the body

Hormone

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

James-Lange Theory

Theory of emotion that suggests that our experience of physiological changes come first, which the brain then interprets as an emotion.

Emotion

A strong feeling or mood that has important motivational properties, it drives an individual to behave in a particular way.

Neuron

nerve cell

Sensory Neuron

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

Motor Neuron

a neuron that sends an impulse to a muscle or gland, causing the muscle or gland to react

Relay Neuron

Nerve cell that transmits electrical impulses from sensory neurons to motor neurons

Inhibitory

Keeps next cell from firing

Excitatory

Causes next cell to fire

Summation

accumulation; total result of inhibitory and excitatory.

Synaptic transmission

The relaying of information across the synapse by means of chemical neurotransmitters.

Soma

Cell body of a neuron

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

Axon

Carries the electrical signal away from the cell body and down the length of the neuron

Myelin Sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

Nodes of Ranvier

Gaps in the myelin sheath to which voltage-gated sodium channels are confined.

Synaptic cleft

The narrow gap that separates the presynaptic neuron from the postsynaptic cell.

Terminal button

the bud at the end of a branch of an axon; forms synapses with another neuron; sends information to that neuron

Dendrites

Branchlike parts of a neuron that are specialized to receive information.

Neurotransmitter

Chemical messengers that cross the synaptic gaps between neurons

Hebb's theory of learning and neuronal growth

An early theory of 'plasticity' in the brain which suggests that learning causes synaptic connections between groups of neurons to become stronger. The groups of neurons are called cell assemblies, and the neuronal growth that occurs between these will create more efficient learning in the brain.

Plasticity

the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

Engram

The physical changes in the brain associated with a memory/learning. It is also known as the memory trace.

Cell assemblies

Ensembles of neurons linked via Hebbian synapses that could store memory/learning traces

Neuronal Growth

When a neuron frequently excites another neuron, it results in change or development in one or both of the neurons.

Reductionist

approach that seeks to define a complex set of facts by a simpler set of facts

Objective

unbiased; not subjective

Frontal Lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

Parietal Lobe

A region of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position

Somatosensory area

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

Occipital lobe

A region of the cerebral cortex that processes visual information

Temporal lobe

A region of the cerebral cortex responsible for hearing and language.

Cerebellum

The "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance

Cerebral Cortex

Outer region of the cerebrum, containing sheets of nerve cells; gray matter of the brain

Motor Area

A region of the frontal lobe involved in regulating movement

Visual Area

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

Wernicke's Area

A brain area involved in language comprehension and expression; usually in the left temporal lobe

Auditory Area

A part of the temporal lobe that receives and processes auditory information

Broca's Area

Controls language expression - an area of the frontal lobe, usually in the left hemisphere, that directs the muscle movements involved in speech.

Localisation of function

Specific functions are served by specific areas of the brain

Montreal Procedure

A surgical procedure to treat epilepsy, originally developed by Wilder Penfield, in which the neurons that produced seizures were surgically destroyed.

Cognitive neuroscience

The scientific study of biological structures that underpin cognitive processes e.g. the hippocampus and it's involved in the formation of memories.

Neurological Damage

Any event, such as illness or injury, which can result is neuron damage in the brain which may lead to a loss of function or change in behaviour.

Stroke

Damage to the brain from interruption of its blood supply.

aphasia

impairment of language, usually caused by left hemisphere damage either to Broca's area (impairing speaking) or to Wernicke's area (impairing understanding).

CT scan

A series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body. Useful for revealing abnormal structures in the brain as higher quality than X-ray but more radiation than a traditional X-Ray and only provides structural information.

PET scan

A visual display of metabolic activity in the brain that detects where a radioactive form of glucose goes while the brain performs a given task. Useful to show the brain in action and can show localisation of function, however expensive, not easy to interpret and ethical issues to do with injection of glucose.

fMRI Scan

A technique for revealing blood oxygen levels in the brain (the haemodynamic response) and, therefore, brain activity by comparing successive MRI scans, showing brain function. Can show localisation, very safe and very clear images but expensive, need to be perfectly still and can come with a 5-second time lag.

Semantic memory

memory for knowledge about the world

Episodic Memory

memory for one's personal past experiences

Summary of James Lange theory

event -> arousal -> interpretation -> emotion