Neuroscience, the brain, and behaviour (ch 4)

Psychology 101

Action Potential

Action Potential

A short-lasting event change in electrical membrane potential associated with the passage of an impulse along the membrane of a muscle cell or nerve cell

Autonomic nervous system

Part of the peripheral nervous system that controls and monitors bodily functions such as heart rate, digestion, respiration rate, salivation, perspiration, and pupil diameter.

Axon

A long, slender projection of a nerve cell or neuron that typically conducts electrical impulses from the cell body to a distant location within the brain. Also known as a nerve fibre.

Basal Ganglia

Large, round masses that lie in each hemisphere and overhang the thalamus and are composed of the caudate nucleus, the putamen, and the globus pallidus. Implicated in disorders of movement and emotional processing.

Behavioural Neuroscience

The application of biological principles to the study of physiological, genetic, and developmental mechanisms of behaviour in humans and nonhumans animals

Broca’s Area

A region of the left frontal lobe associated with the production of speech

Central Nervous System

The body main processing system consisting of the brain and the spinal cord. It is responsible for sending, receiving and interpreting information from all parts of the body

Cerebellum

Meaning “little brain”; attached to the posterior of the hindbrain and associated with dexterity and smooth execution of movement.

Cerebral Cortex

The brain’s outer layer of neural tissue, consisting of two folded sheets of grey matter organized into two hemispheres (left and right)

Cognitive Neuroscience

The scientific study of biological substrates underlying cognition, with a specific focus on the neural substrates of mental processes

Corpus callosum

A thick band of nerve fibres that connects the left and right hemispheres of the brain

Dendrites

Tree-like extensions at the beginning of a neuron that help to increase the surface area of the cell body. They receive information from other neurons and transmit electrical stimulation

double dissociation

the phenomenon by which two cognitive faculties that are believed to be linked in some way can each receive damage while other remains intact and functioning

Electrophysiology

The study of the electrical properties of biological cells and tissues

Event-related potential (ERP)

The measured electrophysiological response resulting from a specific sensory, cognitive or motor stimulus

Excitatory

Excitatory neurotransmitters stimulate the brain. They include norepinephrine and epinephrine.

Frontal Lobe

One of the four parts of the cerebrum, it controls voluntary movement, verbal expressions, problem-solving, willpower, and planning

Functional magnetic resonance imaging (fMRI)

A neuroimaging procedure that measures brain activity by detecting associated changes in blood flow

GABA (<del>y</del> - aminobutyric acid)

The brains main inhibitory neurotransmitter. It is estimated that close to 40% of the synapses in the human brain have GABA recpetors

Gene knockout

A genetic technique in which one of an organism’s genes is made inoperative

Glutamate

The body’s most prominent neurotransmitter and the brain’s main excitatory neurotransmitter

Grandmother cell

A neuron that responds consistently to the sight or concept of one thing, irrespective of incidental changes in the input

Grey Matter

found on the surface of the cerebral hemispheres and of the cerebellum. It contains most of the brains neuronal cell bodies

Hypothalamus

A brain region that contains a number of small nuclei with a variety of functions, including the linking of the nervous system to the endocrine system via the pituitary gland

Inhibitory

Inhibitory neurotransmitters balance mood and are easily depleted when excitatory neurotransmitters are overactive. They include serotonin, GABA, and dopamine.

Limbic system

A complex set of structures that lies on both sides of the thalamus. It includes the hypothalamus, the hippocampus, and the amygdala. It is heavily implicated in emotional processing and the formation of memories

Locus Coeruleus

A small brain area, located at the top of the brainstem, where noradrenergic neurons are localized

Long-term potentiation (LTP)

Prolonged synaptic stimulation that results in long-lasting, strengthened synaptic transmission. The mechanisms underlying LTP may contribute to synaptic plasticity during learning

Neuron

An electrically excitable cell that processes and transmits information through electrical and chemical signals

Neuropsychology

The study of the structure and function of the brain as they relate to specific psychological processes and behaviours

Neurotransmitters

Chemicals the help neurons to communicate with each other and are essential components of the mechanisms that regulate efficient and effective brain functioning

Nucleus accumbens

Located in the midbrain, at the top of the brainstem. It works closely with other brain centres, particularly the ventral tegmental area. These circuits have been heavily implicated in the reward-related behaviors

Occipital lobe

One of four major lobes of the mammalian cerebral cortex. The visual processing centre

Optogenetic

Uses light to control neurons that have been genetically sensitized to light and is used to confirm how neurons make and store memories

Parietal lobe

One of four major lobes of the mammalian cerebral cortex. It integrates sensory information from various modalities, including spatial sense and navigation, touch, temperature, and pain

Plasticity

The brain’s ability to change as a result of experience, skill ,or injury

Psychopharmacology

The discipline that studies the effects of drugs on the brain and behaviour

Raphe nuclei

Serotonin is made in the raphe nuclei of the brainstem, which have projections throughout the brain as well as down into the brainstem. Serotonin release modulated sleep and wakefulness, appetite, pain, mood, and emotion.

Rate coding

The notion that information is coded by the rate of firing of neurons

Receptive field

Most sensory neurons only respond to stimuli when they are presented in particular regions of space. Such a region of space is called a neuron’s receptive field

Simple cells

Cells in the visual cortex that have larger receptive fields because they add together activity from cells lower down the hierarchy of processing

Somatic nervous system

The part of the peripheral nervous system that is responsible for carrying motor and sensory information both to and from the central nervous system

Split-brain patients

Patients who have undergone surgical damage to the corpus callosum to prevent the spread of epileptic seizures. Research with split-brain patients is important for understanding the functions of the two hemispheres

Synapses

Structures that allow a neuron to pass an electrical or chemical signal to another cell

Temporal coding

An alternative to rate coding. The notion that different neurons tend to fire in synchrony with each other and that this may be one way for the brain to code the fact that different properties of an object (or different parts of an object) belong together

Temporal lobe

One of four major lobes of the mammalian cerebral cortex. It is involved in the retention of visual memories, the storage of new memories, the processing of sensory input, and the comprehension of language

Thalamus

Consists of two interconnected egg-shaped masses that lie in the centre of the brain. The thalamus is the main sensory relay for all senses (except smell) between the sense organs and the cortex. It also contains projections to almost all parts of the cortex and the basal ganglia

Transcranial magnetic stimulation (TMS)

The most commonly used technique for brain stimulation. Noninvasive, the method uses a magnet to induce weak electrical currents to cause activity in specific or general parts of the brain with little discomfort

Ventral tegmental area

A group of neurons located close in the midbrain (mesencephalon). It is widely implicated in the drug and natural reward circuitry of the brain

Wada test

A test used to establish cerebral language and memory storage in each hemisphere. Administration of a barbiturate enables each hemisphere to be ‘put to sleep’ one at a time

White matter

A component of the central nervous system consisting mostly of glial cells and myelinated axons. It modulates the distribution of action potentials and coordinates communication between different brain regions