Exam 1 Terms Flashcards
Cells specialized for the conduction and transmission of electrical signals in the nervous system
Neurons
Process in which a substance is released by synaptic terminals for the purpose of transmitting information from one nerve cell to another
Neurotransmission
A functional entity consisting of interconnected neurons that is able to regulate its own activity
Neural circuits
The neuronal process that carries the action potential from the nerve cell body to a target
Axon
A neuronal process arising from the cell body that receives synaptic input
Dendrite
The specialized end of a growing axon (or dendrite) that generates the motive force for elongation
Growth cone
Wrapping around an axon that provides electrical insulation formed by glia cells: Oligodendrocytes or Schwann cells
Myelin
A general term for parts of the central nervous system (CNS) that are rich in axons (rich in lipids)
White matter
Describes parts of the CNS that are rich in cell bodies
Gray matter
Specialized apposition between a neuron and its target cell for transmission of information by release and reception of a chemical transmitter agent
Synapse
Substance released by synaptic terminals for the purpose of transmitting information from one nerve cell to another
Neurotransmitter
Spherical, membrane-bound organelles in presynaptic terminals that store neurotransmitters
Synaptic vesicle
A molecule specialized to bind any one of a large number of chemical signals, preeminently neurotransmitters
Receptor
Referring to the component of a synapse specialized for transmitter release. Upstream of a synapse.
Presynaptic
Referring to the component of a synapse specialized for transmitter reception. Downstream of a synapse.
Postsynaptic
Nerve cells within the nervous system responsible for converting external stimuli from the organism’s environment into internal electrical impulses
Sensory neuron
A nerve cell forming part of a pathway along which impulses pass from the brain or spinal cord to a muscle or gland
Motor neuron
A neuron that innervates other neurons; technically links a primary sensory neuron to a primary effector neuron (reflex arc)
Interneurons
Transmit signals between brain areas
Communication neuron
Extract and process information from input neurons
Computation neuron
A synapse that increases the likelihood of the downstream neuron sending a signal (action potential)
Excitatory synapse
A synapse that decreases the likelihood of the downstream neuron sending an action potential
Inhibitory synapse
Synapse made by a motor neuron on a skeletal muscle fiber
Neuromuscular junction
The axis of symmetry of a bilaterally symmetric organism
Midline
The electrical signal conducted along axons (or muscle fibers) by which information is conveyed from one place to another in the nervous system
Action potential
The visual phenomena where an individual has the ability to depict visual information although they are not entirely conscious of the experience
Blindsight
Anterior end of the brain stem
Midbrain
Ridges of the brain
Gyrus
Grooves of the brain
Sulcus
“Executive function”
- All of neocortex from front to the central sulcus
- Planning, emotional expression, problem solving, memory
- Includes primary motor cortex
Frontal lobe
Fissure that separates the frontal and parietal lobes
Central sulcus
“Sensory information”
- Includes somatosensory cortex
Parietal lobe
- “Vision”
- Processes visual input
- Size indicates importance of vision to humans
Occipital lobe
- “Memory, listening”
- Includes hippocampus: critical in forming long term memories
- Primary auditory perception/processing (hearing)
- Visual memories
Temporal lobe
Portion of the CNS that extends from the lower end of the brain stem
Spinal cord
Cerebellum, pons and medulla
Hindbrain
Relay station (like thalamus); initiates dreams
Pons
Controls involuntary functions such as breathing
Medulla
Regulates motor coordination, posture and balance
Cerebellum
Midbrain, pons and medulla
Brainstem
200+ million axons connecting the two hemispheres
Corpus callosum
Dividing brain regions into evolutionary age:
- Lizard brain (brain stem, cerebellum - flight or fight)
- Mammalian brain (limbic system - emotions, memories, habits)
- Human brain (neocortex - language, abstract thought, imagination, consciousness)
Tribune Brain Theory
Pseudoscience primarily focused on measurements of the human skull, based on the concept that the brain is the organ of the mind, and that certain brain areas have localized, specific functions or modules
Phrenology
Neocortical regions not involved in primary sensory or motor processing; carries out tasks not associated with a single sense
Association cortex
Frontal lobe area specialized in the production of language
Broca’s Area
Temporal lobe area that mediates language comprehension
Wernicke’s Area
Physical representation of the body located within the brain
- Motor homunculus: motor neurons projected out
- Sensory homunculus: sensory neurons projecting in
Homunculus
Also called somatosensory or sensory cortex – the region of the neocortex concerned with processing of sensory information
Somatic sensory cortex
Group of neurons with similar properties that represent a functional unit within the neocortex. The basic unit of the neocortex, repeated many times.
Neocortical or minicolumn
Subcortical brain structures that are crucial in planning, organizing and executing movement, addiction
- Functions with the frontal lobes
- Caudate, putamen, globus palladus, substantia nigra, subthalamic nucleus
- Produces a lot of dopamine: involved in addiction
Basal ganglia
Nucleus in the basal ganglia involved in initiating voluntary movement
- Dopaminergic neuron die in Parkinson’s disease
- Dopamine metabolism: black coloration
Substantia nigra
Cortical and subcortical structures concerned with emotions and memory
Limbic system
Part of the temporal lobe involved in consolidation of
short-term memories into long-term memories (cortex)
Hippocampus
Major part of the limbic system, monitors progress towards goals
Cingulate gyrus
A nuclear complex in the temporal lobe whose major functions concern autonomic, emotional and sexual behavior; most often connected with the major emotions such as fear and avoiding situations that induce fear
Amygdala
Imaging technique that uses a combination of radio waves and magnetic fields to scan the brain or a body part; generates a static image
Magnetic Resonance imaging (MRI)
Uses MRI techniques to image blood flow, which reflects neuronal activity; multiple images are taken over time to generate a dynamic view, albeit at much lower resolution than a standard MRI scan
Functional magnetic Resonance imaging (fMRI)
Variation of MRI that measures movement of water molecules along axons; allows tracing of brain wiring
Diffusion Tensor Imaging
Radioactive sugar or glucose injected
which is taken up by active neurons; emitted positrons annihilate and convert to gamma rays which are detected
Positron Emission Tomography
Delivery of low current to brain region of interest via electrodes on the scalp. Thought to the likelihood that neurons will fire (neuronal excitability)
Transcranial Direct Current Stimulation (tDCS)
Implantation of a electrode or device to deliver electrical stimulation to a region effectively inactivating the region
- Parkinson’s disease: Globus palidus and other regions
- Multiple sclerosis: Thalamus
Deep Brain Stimulation
Uses x-rays from many different angles and a computer to build up an image of the brain or body
Computerized Tomography (CT) scan
- Memory of “autobiographical” events
- Event is linked to when and/or where you learnt something (emotions, personal experience, “episodes”)
- Recalling where you were when Kennedy was shot
- Warning: autobiographical memory is more than just episodic
Episodic memory
- “Factual” memory
- Ideas and concepts not drawn from personal experience
Semantic memory
Memories held briefly in mind that enable a particular task to be accomplished (e.g., efficiently searching a room for a lost object)
Working memory
Ability to learn; Pavlov pairing a bell with food
Associative memory
Use of a placebo group in clinical trials or tests
Control
Random assignment of test subjects to experimental and control (placebo) groups; neither the subjects nor the experimenters know who is in which group
Double blind study
Experimenters know who is in which group
Single blind
Must be included in studies
Statistics
Recording activity, say in fMRI, before asking test subject to perform task
Baseline
Any treatment used to ameliorate a symptom or disease, but is actually ineffective for the condition
Placebo
Surgical severing of the corpus callosum (usually to control grand mal seizures); brain sides function independently
Split brain patient
Harmless substance that when taken by a patient is associated with harmful effects due to negative expectations or the psychological condition of the patient
Noceibo
Having a psychological origin
Psychogenic
Difficulty comprehending language due to damage to these areas (or others)
Aphasia
Inability to name objects
Agnosia
