2: Neurological basis of human behavior Flashcards
What alters the ion concentration within the membrane and activates the 2nd messenger cascade?
passage of calcium
Polarized, elongated cells capable of instantaneous, intracellular communication
Neurons
What do you call the instantaneous pulses of membrane depolarization?
Action potential
It increases the rate of action potential along the axon
Myelin sheath
Receptors of gray matter
Neuronal cell bodies
Receptors of white matter
Myelinated axon tracts
Responsible for regulation of extracellular environment
Glial cells
Ensure the synaptic communication and regulate extracellular ion concentrations
Astrocytes
What triggers the release of chemical neurotransmitters? Where would it enter?
Action potential, the synaptic cleft
What serves as insulator in the fiber tracts?
Oligodendrocytes
What do you call the immune system cells?
Microglia
It refers to the local organization of neurons
Cytoarchitecture
How many columnar organizations acquire specific function? (Cytoarchitecture)
47 areas
Sensory receptors functions as what?
Transducers
True or false: Ontogeny recapitulates phylogeny
TRUE
True or false: the lower centers inhibit the higher centers
FALSE
What comprises the nervous system?
Sensory and motor systems, and the associated units
What system processes external stimuli into neuronal impulses?
Sensory system
It enables people to manipulate the environment and to influence others’ behavior through communication
Motor system
It creates an internal representation of the external world
Sensory system
Where are the sensory inputs integrated w/ internal drive and emotional stimuli?
Associated units
This is where the emotional stimuli drive the actions of the motor units
Associated units
What is the basic unit of behavior?
Reflex arc
What comprises the reflex arc?
Receptor Sensory/affernet neuron Synapse in the CNS Motor/efferent neuron Effector
Sensory inputs
Auditory, gustatory, visual, olfactory, tactile
Responsible for the basis of reasoned thought
Sensory system
State of heightened suggestibility
Hypnosis
The corpus striatum is comprosed of:
Caudate and putamen
Gross distortions of perception of any sensory modality and may depend on person’s goals and emotional state
Hypnosis
Produce gross coordinated movements of the entire body
Brainstem
Controls fine movements and dominates the brainstem
Corticospinal tract
Where is the motor strip (for planned movements) located?
Posterior frontal lobe
Subcorticate matter that mediates postural tone
Basal ganglia
What are the four distinct ganglia? (w/in basal ganglia)
Striatum
Pallidum
Substantia nigra
Subthalamic nucleus
Decreased activation of corpus striatum
OCD behavior
Gate keeper that allows the motor system to perform only goal-oriented acts
Corpus striatum
Overactivity of the corpus striatum is due to what?
Lack of dopaminergic inhibition
An inability to initiate movements due to overactivity of the striatum
Bradykinesia
Receives inputs from the corpus striatum and project fibers into thalamus
Globus pallidus
Yields ballistic movement and sudden limb jerks
Subthalamic nucleus
Where melanin pigment can be seen
Substantia nigra
Degenerates into Parkinson’s disease
Substantia nigra
Capable of initiating and maintaining the full range of useful movements
Nuclei of basal ganglia
3 main processing blocks of the association cortex (basic organization of the brain)
Posterior cortex
Frontal cortex
Brainstem and the thalamic reticular activating system
One of the nucleus of the limbic system that receives fibers from all sensory areas
Amygdala
How are the primary sensory cortices for touch,vision,hearing,smell and taste represented? (Hemispheric lateralizarion)
Bilaterally
Responsible for generating and modifying memories and for assigning emotional weight to sensory and recalled experience
Limbic system
Generates programs and executes plans (highest level)
Frontal cortex
Integrates perception and generates language
Posterior cortex
Gate for the assignment of emotional significance to memories
Amygdala
Occipital lobe is responsible for what two functions?
Vision
Visual perception
Tactile sensation, visuospatial function, reading and calculation are functions of what lobe?
Parietal lobe
The temporal lobe is responsible for:
Audition Language comprehension Sensory prosody Memory Emotion
Voluntary movement, language production, motor prosody, comportment, executive functions and motivation are functions of what lobe?
Frontal lobe
Language production is a function of:
Frontal lobe
What causes changes in personality?
Bilateral lesions
Slowed thinking, poor judgement, decreased curiosity, social withdrawal and irritability are symptoms of:
Frontal lobe syndrome
Causes of frontal lobe syndrome:
Trauma, infarcts, tumors, lobotomy, multiple sclerosis, Pick’s disease
Apathy to sudden impulsive disinhibition
Frontal lobe syndrome
Establishment and maintenance of awake state
Arousal
Absence of arousal will lead to:
Stupor and coma
Skill of maintaining a coherent line of thought:
Attention
Attention is maintained by what lobe?
Right frontal lobe
Brain regions of arousal:
Brainstem
ARAS
Cortex
It sets the level of consciousness:
Within brainstem-ARAS
Major causes of confusion:
Infectious Metabolic Toxic (drugs) Vascular (stroke, SAH) Neoplastic Traumatic (brain injury)
Metabolic causes of confusion are:
Hypoxia
Hypoglycemia
Uremia
Hepatic disease
Implicit in the concept of attention and ability to follow train of thought, functions over a period of seconds:
Immediate memory
Ability to store information and relate to cognitive information:
Working memory (categorized under recent memory)
Applies on the scale of minutes to days
Recent memory
Encompasses months to years:
Remote memory
Rates the emotional importance of an experience and to activate the level of hippocampal activity:
Amygdala
What lobe houses the hippocampus?
Medial temporal lobe
Significant site for formation and storage of immediate and revent memories:
Hippocampus
What side of the hippocampus is for non-verbal memories?
Right
The side of hippocampus efficient for forming verbal memories:
Left
What lobe is for the memorized motor acts?
Median temporal lobe
The left parietal cortex is responsible for:
Highly skilled acts
For formation of memory (dorsal medial nucleus of thalamus and mamillary bodies)
Diencephalon
Causes of amnesia:
Alcoholism, seizures, migraine, drugs, vitamin deficiencies, trauma, stroke, tumor infections, degenerative disorder
Degeneration of neurons and replacement by senile plaques; most common memory disorder.
Alzheimer’s disease
Impaired language comprehension and visuospatial organization in Alzheimer’s disease would affect what lobe?
Parietal lobe
What disease is characterized by severe inability to form new memories and inability to recall and more common in chronic alcoholics due to thiamine deficiency?
Korsakoff’s syndrome
True or false: The dominant hemisphere for language directs the dominant hand.
TRUE
This can clearly demonstrate the hemispheric localization of function:
Language
Name the 3 levels for language comprehension processing:
Phonological processing
Lexical processing
Semantic processing
It connects the words to their meaning:
Semantic processing
For individual sounds:
Phonological processing
Matches the phonological input with recognized words:
Lexical processing
It is derived from the basic drives: feeding, sex, pleasure, pain, fear and aggression.
Emotion
Where are the other distict human emotions, like affection, pride, guilt, pity, envy, and resentment, learned and represented?
In the cortex
True or false: The interplay of emotions is far beyond the understanding of neuroanatomists.
TRUE
What hemisphere houses the analytical mind? (Hemispheric dichotomy of emotional representation)
Left hemisphere
What appears dominant for affect, socialization and body image? (Hemispheric dichotomy)
Right hemisphere
Appears to lift the mood (hemispheric dichotomy)
Left prefrontal cortex
What causes depression? (Hemispheric dichotomy)
Right prefrontal cortex
What houses the emotional association areas which directs the hippocampus to express motor and endocrine components of the emotional state?
Limbic system
The hippocampus, fornix, mamillary bodies, anterior nucleus of thalamus and cingulate gyrus are part of:
Limbic system: papez circuit (1937)
What do you call the study of the chemical interneuronal communication and the translation of the action potential into chemical neurotransmission?
Neurophysiology and neurochemistry
It is the process involving the release of a neurotransmitters by one neuron and the binding of the neurotransmitter molecule to a receptor on another neuron.
Chemical neurotransmission
What do anti-psychotics do?
Block D2
What do anti-depressants do?
Increase the amount of serotonin or norepinephrine
GABA receptors are classified as what?
Ion-channel linked receptor
Chemical signals that flow between neurons:
Neurotransmitters
Happens between the presynaptic and postsynaptic membranes in which NT concentrations in synaptic cleft are regulated by feedback inhibition of NT release.
Synapse
Synthesis of all NT (except peptide NT w/c is synthesized in cell bodies) that is influenced by Ca+ influx, CAMP levels and circulating hormones
Presynaptic components
What causes depolarization of the postsynaptic membrane?
excitatory NT
NT receptors are the sites of action for many psychotherapeutic and psychoactive drugs
Postsynaptic components
What is the principal function of the postsynaptic components?
To alter the electrical transmembrane potential and inc or dec the likelihood of AP
The sensitivity of receptors is influenced by the following:
- # of receptors present
- The affinity of the receptor for the NT
- Efficiency w/ which the binding of NT to receptor is translated as intraneuronal message
Where are the biogenic amines (eg.dopamine,epinephrine,serotonin,ACH,histamine) synthesized?
Axon terminal
What is the amino acid precursor of serotonin?
Tryptophan
What is the AA precursor of dopamine, norepinephrine and epinephrine?
Tyrosine
3 most important dopaminergic tracts:
- nigrostriatal tract
- mesolimbic-mesocortical tract
- tuberoinfundibular tract
In this tract, the cell bodies are in the substantia nigra and corpus striatum
Nigrostriatal tract
Tract in which the cell bodies are in the ventral tegmental area adjacent to the SN, CC and LS and mediate effects of anti-psychotic drugs:
Mesolimbic-mesocortical tract
Tract in which the arcuate nucleus and the periventricular area of hypothalamus and project to the infundibulum and anterior pituitary
Tuberoinfundibular tract
What are the dietary variations of low and high tryptophan (serotonin)?
LOW: irritability, hunger
HIGH: sleep, relieve anxiety, increase sense of well-being
Contain the building blocks of protein
Amino acid
Acts as a release-inhibiting factor of prolactin in the anterior pituitary:
Dopamine
Refers to the chemical bod between carboxylic acid group and the amino group of adjacent amino acids in a protein:
Peptide
True or false: peptides differ from other neurotransmitters.
Why?
TRUE. Because they are manufactured in the cell bodies and not in the axon terminal.
Inhibitory amino acid:
GABA (Gamma-aminobutyric acid); monocarboxylic amino acid
Amino acids in the brain:
Glutamate and aspartate
Excitatory amino acid:
Glutamate; dicarboxylic amino acid
What are the two major amino acids?
Glutamate and GABA (gamma-aminobutyric acid)
AA synthesized from glucose and glutamine in the presynaptic neuron terminals and stored in the synaptic vesicles:
Glutamate
The glutamate receptor that plays an essential role in learning and memory and psychopathology:
N-methyl-D-aspartate (NMDA) receptor
What is the primary neurotransmitter in cerbellar granule cells, striatum and cells of hippocampus?
Glutamate
What stimulates the release of glutamate?
Nicotine
What is the primary neurotransmitter in intrinsic neurons that function as local mediators for the inhibitory feedback loops?
GABA
True or false: GABA crosses the blood-brain barrier.
FALSE
GABA is found most exclusively in the:
Central nervous system
GABA is synthesized from glutamate by what rate-limiting enzyme and cofactor?
Glutamic acid carboxylase, pyridoxine (Vit B6) as cofactor
May serve a neuromodulary role at some synapses
Peptides
