Behavior Flashcards
Amino acid neurotransmitters
Excitatory neurotransmitters: glutamate
Inhibitory neurotransmitters: GABA (in the CNS) and glycine (in the PNS)
Peptide neurotransmitters
Opioids (such as endorphins), which are involved in the perception of pain
Monoamine neurotransmitters
Include catecholamines, including epinephrine, norepinephrine, and dopamine
Contain one amino group connected to an aromatic ring by a two-carbon chain
Muscle contracts in response to being stretched while the antagonist muscles relax, to regulate muscle length
Stretch reflex
Abnormalities of the lower motor neurons cause fasciculations, decreased muscle tone, and decreased reflexes
Lower motor neuron signs
Abnormalities of the upper motor neurons cause clonus, extensor plantar response, increased muscle tone, and increased reflexes
Upper motor neuron signs
Rhythmic contractions of antagonistic muscles
Most commonly, the ankle dorsiflexes and plantarflexes involuntarily back and forth in quick succession
Clonus
Increased tone of skeletal muscle resulting in increased muscle tension but reduced muscle strength
Hypertonia
Hard object scraped on bottom of foot results in extension and abduction of toes (abnormal response)
Normal response is flexion of toes
Also called Babinski reflex
Extensor plantar response
Brain and spinal cord
Brain includes cerebral hemispheres, cerebellum, brainstem (midbrain, pons, medulla)
Central nervous system (CNS)
Nerves and ganglia beyond the brain and spinal cord
Peripheral nervous system (PNS)
Sensation including position sense, vibration, touch, pain, and temperature
Somatosensation
sensory neurons that carry signals toward the central nervous system
Afferent neurons
Mnemonic: Afferent and efferent sound the SAME. Sensory Afferent Motor Efferent
motor neurons that carry signals toward the muscles
Efferent neurons
Mnemonic: Afferent and efferent sound the SAME. Sensory Afferent Motor Efferent
Left brain controls right side of body and vice versa.
This applies to all senses except for smell
Contralateral control
Dominant hemisphere
Dominant hemisphere in most people is the left side
Dominant hemisphere: controls language and math functions
Non-dominant hemisphere: controls music, emotional processing
Gray versus white matter
Gray matter = neuron somas (bodies)
White matter = myelinated axons of neurons
located in the occipital lobe, processes direct visual input from the retinas.
The primary visual cortex.
The secondary visual cortex then further processes information from the primary cortex.
Develops during adolescence
Regulates high level executive functions like planning, decision making, considering the future
Anterior portion of the frontal lobe
Prefrontal Cortex
Located under the cerebrum
Primary functions: coordinates movement and regulates sense of position
Abnormalities in this structure will cause loss of balance
Cerebellum
Contains the midbrain, pons, and medulla
brainstem
Three major areas of the frontal lobe, each with a primary function:
1) motor cortex (body movement)
2) prefrontal cortex (executive function)
3) Broca’s area (speech production)
Mnemonic: think of planning (prefrontal) and giving a speech (Broca’s) with gestures (motor) in front of the class
Two primary functions of the parietal lobe:
1) somatosensory cortex (touch/pressure/pain)
2) spatial manipulation (3D orientation)
Mnemonic: Think of a pat on top of the head, feeling the sense of touch and where it is located
Lobe responsible for processing visual input
Occipital lobe
Three primary functions of temporal lobe:
1) sound
2) Wernicke’s area (language comprehension)
3) memory/emotion
Mnemonic: Think of tempo – listening to sound, understanding the rhythm of speech, enjoying and remembering it
Part of the brainstem that regulates arousal and alertness
Reticular formation
12 pairs of nerves that perform important functions and come out of the brainstem
cranial nerves
The part of the brainstem that regulates waking and relaxing
Pons
Mnemonic: Think about waking up and relaxing by a peaceful pond
The part of the brainstem that regulates autonomic activity of the heart and lungs
Medulla
White matter structure that transmits motor signals through the corticospinal pathway (cerebrum)
Internal capsule
White matter structure that connects the two hemispheres
Damage causes disconnect in information processing between the two hemispheres, for example being able to draw but not vocalize something seen on the right side. (cerebrum)
Corpus callosum
Hemispheric lateralization (cerebrum)
Specialization of each cerebral hemisphere for certain cognitive functions right hemisphere vs left hemisphere
Right hemisphere = visuospatial, emotional, artistic/musical processing
Left hemisphere = linguistic and analytic processing
Synapse formed by contact between a motor neuron and a muscle fiber
Neuromuscular junction
Upper vs lower motor neurons (PNS)
Upper motor neurons: Located in the brain and spinal cord
Lower motor neurons: synapse between the PNS and skeletal muscle, forming a neuromuscular junction
Most common excitatory neurotransmitter
The reticular activating system has diffuse projections of glutamate to the cerebral cortex
Associated with increased cortical arousal
glutamate
Most common inhibitory neurotransmitters
GABA is found in the brain while glycine is found in the spinal cord
GABA and glycine
High concentration of this neurotransmitter in nucleus basalis and septal nuclei of the frontal lobe
Released in the neuromuscular junction of lower motor neurons
Acetylcholine
High concentration of this neurotransmitter in hypothalamus with projections to the cerebral cortex
Histamine
High concentration of this neurotransmitter in the brainstem in the pons, specifically the locus coeruleus
Also located in the autonomic nervous system, but at lower concentrations compared to acetylcholine
Norepinephrine
High concentration of this neurotransmitter in brainstem at the raphe nuclei
serotonin
High concentration of this neurotransmitter in ventral tegmental area and substantia nigra, which project to the striatum
Low concentration of dopamine in the striatum leads to Parkinson’s disease
Associated with experience of pleasure, and contributes to maintenance of addictive behaviors
dopamine
Series of X-rays to that are combined into a composite image to create three dimensional image
Compared to MRI: Lower resolution than MRI, not as good for soft tissue detail, but much faster and better for bony structures
Computerized Axial Tomography (CAT or CT scan)
Radiowaves with magnetic fields to disrupt orientation of atoms. Realignment results in signals used to create MRI three dimensional imaging
Slower than CT scan, but higher resolution and better for soft tissue
Magnetic Resonance Imaging (MRI)
Electrodes placed externally on scalp, non-invasive
Used to measure brain electrical activity
Can give information about seizures or sleep stages
Electroencephalogram (EEG)
Also known as SQUIDS - Superconducting Quantum Inteference Device. Measures brain electrical activity like EEG
Compared to EEG: higher resolution, but requires large machine and special room
Magnetoencephalogram (MEG)
Form of MRI that allows for visualization of which regions of brain are active
Measures relative amounts of oxygenated versus deoxygenated blood in the brain, thus allowing us to determine what brain areas are being used for a given task
Functional MRI (fMRI)
Combined with CT or MRI, allow for visualization of cellular activity
Provide radioactive drug (tracer) and see where the tracer is located after certain period of time
Positron Emission Tomography (PET)
Links the central nervous system and the endocrine system via the pituitary gland
Hypothalamus
The master gland
Anterior produces FSH, LH, ACTH, TSH, Prolactin, Endorphins, GH
Posterior produces ADH, oxytocin
Mnemonic: FLAT PEG for anterior pituitary
Pituitary gland
Regulates body metabolism
Produces T3 and T4
thyroid gland
Four glands located on thyroid
Produces parathyroid hormone
Regulates calcium
Parathyroid glands
Located on top of kidneys
Cortex, or outer component, is responsible for producing aldosterone, cortisol, and androgens
Medulla, or inner component, is responsible for producing epinephrine and norepinephrine
Adrenal glands
In females, the ovaries, and in males, the testes
Stimulated by FSH/LH to release sex hormones (progesterone and estrogen in females, testosterone in males)
gonads
Regulates blood sugar
Acts independent of the pituitary gland
Pancreas
