Agonist- a drug that has an facilitory effect on a particular synapse
AMPA Receptor- an ion channel activated by glutamate bonding that controls sodium concentration in the neuron the AMPA receptor facilitates action potential propagation
Amygdala- a structure of the limbic system, thought to play a role in integrating emotional content into cognition and behavior
Antagonist- a drug that has an inhibitory effect on a particular synapse
Anterior Thalamus- receives projections from the basal ganglia and projects to the motor cortex
Axon- the portion of the neuron wherein an action potential transmits a signal from the cell body to the terminus
Basal Forebrain- contributes to emotional regulation, part of the limbic system located on the rostral most aspect of the limbic system
CA1 Field- receives input from field CA3 via Schaffer collateral and projects back towards the entorhinal cortex
CA3 Field- receives input from the dentate gyrus via mossy fibers and projects to the field CA1
Cingulate Gyrus- part of the limbic cortex that integrates the functions of the limbic system with those of the frontal cortex
Dendrite- a tree-like extension at the top of a neuron that receives information from other neurons in the form of neurotransmitters
Dentate Gyrus- a region in the hippocampus that receives input from the entorhinal cortex and projects to the field CA3
Depolarization- a reduction towards zero of the membrane potential from its resting potential due to the influx of positively charged ions such as Na+; causes the propagation of an action potential
Entorhinal Cortex- a region in the limbic cortex; provides the main source of input into the hippocampal formation, projects to the dentate gyrus
Fornix- a bundle of fibers connecting the hippocampus with other regions of the brain
Glucocorticoid Receptor-a steroid hormone receptor that influences DNA transcription in response to corticoid binding
Glutamate- an amino acid; the most prevalent excitatory neurotransmitter
Hebb's Rule- if a synapse is repeatedly active at the same time as the postsynaptic neuron fires, structural changes will take place which will increase the strength of that synapse
Hippocampus- a structure of the limbic system, thought to play a key role in learning and memory formation
Ion- an atom that has either a negative or a positive charge due to the gain or loss of an electron
Limbic System- a group of structures including the hippocampus, amygdala, parts of the cortex and parts of the hypothalamus that functions as the motivation and emotional center of the brain
Locus Coeruleus- a group of neurons located in the dorsal pons involved in arousal and vigilance; releases norepinephrine
LTD- a long-term decrease in the size of the postsynaptic response to synaptic transmission
LTP- a long-term increase in the size of the postsynaptic response to synaptic transmission
Mammilary Bodies- bundles of neurons located at the base of the brain that receives input from the hippocampus via the fornix
Medial Septum- supplies the main input to the hippocampus, activity of these neurons is responsible for the rhythmic firing that establishes LTP
Mineralocorticoid Receptor-a steroid hormone receptor that influences DNA transcription in response to corticoid binding
Mossy Fibers- a thick bundle of axons that connects the dentate gyrus to the field CA3
Neurotransmitter- a chemical released from the terminus of an axon; can have either an excitatory or inhibitory effect on a postsynaptic neuron
NMDA- an ion channel that controls Ca2+ influx, the NMDA receptor is generally blocked by a Mg2+, which is ejected as a result of glutamate bonding the NMDA receptor is involved in LTP
Opiate- a class of analgesic drugs derived from the opium poppy
Perforant Path- a bundle of axons that connects the entorhinal cortex to the dentate gyrus
Phosphorylation- the process of activation whereby an enzyme binds a phosphate group to a molecular complex
Pyramidal Cell- a large pyramid-shaped neuron located in the hippocampus and cerebral cortex
Raphe Nucleus- a group of nuclei located in the reticular formation of the medulla, pons and midbrain containing serotonergic neurons; activation causes locomotion and cortical arousal
Schaffer Collateral- neural pathway that connects the CA3 field to the CA1 field
Subiculum- the area that is the primary target of the CA1 field of the hippocampus; location of final stages of memory processing
Synapse- the space between two neurons; site of neurotransmission
Upregulation- an increase in the number and density of a particular neuronal receptor, generally in response to an altered amount of neurotransmitters present in the surrounding environment
Ventral Tegmental Area- a group of neurons located in the midbrain, projects to the nucleus accumbens; key component involved in the reward pathway, reinforcement and attention