Structural Plasticity (Exam 1) Flashcards
Case Study: Orlando Serrell
10 years old, hit in the head with a baseball
&
Acquired savant syndrome (could remember any day/date of week/weather on most of the days
Savant Syndrome
Presentation of extraordinary scholarly skills that emerge after an individual suffers a TBI or other related event.
How to forget faster
- Don’t sleep
- Stress out
- Overextend yourself
- Deprive your senses (engage your senses to make associations)
- Be apathetic (be interested)
Neuroscience
The study of the brain and the rest of the nervous system
Ancient Egyptians
tossed the brain because they felt the brain was useless and more interested in the midbody
Nervous system
organ devoted to the distribution and processing of signals that affect biological functions throughout the body
Central Nervous system (CNS)
the part of the vertebrae nervous system consisting of the brain and spinal cord
Peripheral Nervous System (PNS)
Consists of nerve fibers that connect to sensory receptors (for example, visual receptors in the eye to touch receptors in the skin) to the CNS and other fibers that carry signals from the CNS backout to the muscles and organs.
The Human Brain
Size of a newspaper layer out, 2 millimeters thick
Cerebral Cortex
the tissue covering the top and sides of the brain in most vertebrates is by far the largest structure of the human brain.
***Cortex = Latin for “bark” or “rind”
Frontal Lobe
part of the cerebral cortex positioned at the front of the human brain, enables person to plan and perform actions
Parietal Lobe
the part of the cerebral cortex lying at the top of the human brain; important for processing somatosensory (e.g., touch) inputs
Temporal Lobe
part of the cerebral cortex lying at the sides of the human brain; important for language and auditory processing and for learning new facts and forming new memories of events
Occipital Lobe
part of the cerebral cortex lying at the rear of the human brain; important for visual processing
Cerebellum aka “Little Brain”
brain region lying below the cerebral cortex in the back of the head. It is responsible for the regulation and coordination of complex voluntary muscular movement, including classical conditioning of motor-reflex responses.
Brainstem
group of structures that connect the rest of the brain to the spinal cord and plays key roles in regulating automatic functions such as breathing and body temperatures.
Structural neuroimaging
techniques (e.g., MRI) for creating images of anatomical structures within the living brain
Functional brain imaging
shows what brains are doing at the time of the imaging
Magnetic resonance imaging (MRI)
an imaging technique in which changes in magnetic fields are used to generate images of internal structure
Lesion
damage by injury or illness
Diffusion tensor imaging (DTI)
measures connections between brain regions, enabling researchers to study how major pathways between different brain regions change over time
Dendrites
synapse with axons from other neurons that modulate activity. They receive signals from other neurons.
Cell body (soma)
integrates signals from the dendrites. Combines effects of other neurons
Axons
transmits electrical signals to dendrites that monitor ongoing activity.
Glia
cells of various types that provide functional or structural support to neurons; some contribute to changes in connections between neurons
Astrocytes
glia that line outer surface of blood vessels in the brain and may help in the transfer of oxygen and nutrients from the blood to the neurons
Oligodendrocytes
Wrap the axons of nearby neurons in myelin, a fatty substance that insulates electrical signals transmitted by neurons
Myelin
fatty sheath coating axons (pulse factor)
Plasticity
the capacity of brain structure to change overtime (by experience)
Imprinting
newborn animal forms a lifelong attachment to whatever movements it views early on - typically those of animal mother.
Short time frame, very first memory
How we experience changes in Brain Structure
Involves: Classical Conditioning, Perceptual Learning, and Operant Conditioning
Environmental Enrichment
- More opportunities for learning social interactions and exercise = visible changes in neurons
- More stimulation and opportunity to explore and learn
Neuronal connectivity
the connections between neurons through which brain systems interact.
Hebbain Learning
Principle that learning involves strengthening the connections of coactive neurons; often started as “neurons that fire together, wire together.”
Reflex
an involuntary and automatic (unlearned) reponse
Palmar Grasp
when placing a finger or stroking the inside of the palm, a newborn at 4 months old will respond by closing the hand
Descartes
reflexes = hydraulic movements caused by spirits flowing from the brain to muscles
Current
nerve fibers (bundle of axons) connecting the muscles to the spinal cord - one for sensory and one for motor.
Bell-Magendie law of neutral specialization
the law that sensory and motor neurons are separate and run in two parallel nerve pathways
Nerve pathways
- Spinal cord controls reflexes
- sensory fibers enter the spinal cord and connect to motor fibers
- some fibers travel to the brain
- brain processes inputs and produces outputs
- some travel back down spinal cord and out to muscles
Thalamus
Sensory relay of information
Incoming stimuli —–> sensory pathway into the brain
Outgoing Response
- Visual input from your eyes —–> V1
- Frontal lobes coordinate necessary plans for grasping the cup ——> M1
- M1 outputs thru brainstem to sets of fibers in the spinal cord and out to your arms and fingers
- Basal ganglia and cerebellum continuously track movement making adjustments
Functional Magnetic Resonance Imaging (fMRI)
Method of functional neuro imaging based on comparing an MRI of the brain during performance of a task with an MRI of the brain at rest.
Electroencephalography (EEG)
measures electrical activity in the brain
Greek enkephalos means “brain”
Event related potentials (ERPs)
EEGs from a single individual averaged over multiple repetitions of an event (e.g., repeated stimulus presentation)
Neurophysiology
study of activity and function of neurons
Single-cell recording
use of an implanted electrode to detect electrical activity (spiking) in a single cell (e.g, neuron) ——–> animal research
Mnemonics
study and development of systems for improving and assisting memory
Highly superior autobiographical memory (HSAM)
or Hyperthymesia
ability to access memories of events that happened on almost any day of their lives and can recall seemingly trivial details such as the meals they ate each day
False memories
memories that feel more real than they are
false narrative
Looking for memories (2 Themes)
(perception at encoding vs perception at recalling)
- Many memories are stored in the cerebral cortex
- They are stored in connections between cortical neurons
Neuropsychology
branch of psychology that deals with the relationships between brain function and behavior
Engram
physical change in the brain that forms basis of a memory
Theory of equipotentiality
theory that memories are stored globally by the brain as a whole rather than in one particular brain area.
Karl Lashley discovered
- engrams are not stored in specific cortical areas
- did not prove that the cortex is as spectacularly flexible as he thought
Synapse
narrow gap between two neurons, across which chemical messages can be transmitted
presynaptic
on the sending side of the synapse
postsynaptic
on the receiving side of the synapse
neurotransmitter
one of several classes of molecule released by neurons to carry chemical messages to other neurons
receptor
specialized molecule located on the surface of a neuron, to which one or more particular neurotransmitters can bind; when a neurotransmitter activates a receptor, effects may be initiated in the neuron.
Neuromodulators
neurotransmitter that acts to modulate activity in a large number of neurons rather than a single synapse
synaptic plasticity
ability of synapses to change as a result of experience
Long-term potential
a process by which synaptic transmission becomes more effective as a result of recent activity; with long-term depression, LTP is widely believed to represent a form of synaptic plasticity that could be the neural mechanism for learning.
Long-term depression
the process by which synaptic transmission becomes less effective as a result of recent activity; with LTP, LTD is widely believed to represent a form of plasticity that could be the neural mechanism for learning (weakening)
How researchers change Brain Activity
- Electromagnetic stimulation of neurons
- Transcranial magnetic stimulation (TMS)
- Transcranial direct-current stimulation (tDCS)
Drugs
chemical substances that alter the biochemical functioning of the body and, in many cases, affect the brain
Alter synaptic transmission: neurotransmitter release, activation of postsynaptic receptors, neurotransmitter inactivation, and neurotransmitter reuptake.
Amphetamine
increases dopamine release —–> synaptic neurons receive stronger, more frequent messages
Dopamine involved in reward
pleasurable anticipation or excitement
SSRIs (Selective Serotonin Reuptake Inhibitors)
- Neurotransmitters used in some antidepressants
- Reduce the rate at which serotonin is cleared from synapses
