Limbic System & Reticular Formation Flashcards
what are the components of the limbic association cortex (behavioral response)
orbitofrontal gyrus
cingulate gyrus
parahippocampal gyrus (entorrhinal and perirhinal cortex)
temporal pole
what part of the limbic system is responsible for memory?
hippocampal formation- hippocampus, subiculum, dentate gyrus
what part of the limbic system is responsible for emotions?
amygdala
what part of the limbic system connects the hippocampus to the hypothalamus?
fornix to the mammillary bodies
what part of the limbic system is responsible for reward?
ventral striatum
what thalamic nuclei are part of the limbic system?
anterior, medial dorsal, and midline nuclei
what hypothalamic nuclei are part of the limbic system?
mammillary, ventromedial nuclei, lateral hypothalamus
what are additional components of the limbic system?
habenula
periaqueductal grey
reticular formation
cingulate gyrus breakdown
subgenual - depression
anterior - physical and emotional pain
middle - motor
posterior - sensory and memory
where does the anterior cingulate gyrus receive input from
medial dorsal nucleus of thalamus
where does the orbitofrontal cortex receive information from
all sensory modalities and reward centers
what is the oribtofrontal cortex used for
emotional decision making
major component of addiction
where is the hippocampal formation located
on the floor of the inferior horn of the lateral ventricle
shaped like a seahorse
what are the three parts of the hippocampal formation
dentate gyrus
hippocampus
subiculum
where is the fornix? what does it do?
dorsal to the hippocampal formation
connects hippocampal formation to mammillary bodies
what occurs in the hippocampal formation? what does damage here cause?
memory consolidation, also deals with the link between stress and emotions
anterograde amnesia
where does the entorhinal cortex gather info from?
limbic association cortices
hippocampal formation input
entorhinal cortex to dentate gyrus
to hippocampus
to subiculum
hippocampal formation output 1
subiculum to entorhinal cortex and amygdala
hippocampal formation output 2
subiculum to fornix to mammillary bodies to anterior nucleus of thalamus to cingulate gyrus
the hippocampus sends axons through the fornix to what
the septal nuclei
amygdala stimulation and damage
stimulation - fear and anxiety
damage - inability to recognize facial expression or emotional content of speech
what are the three nuclei of the amygdala
basolateral, central, cortical
what does the basolateral nucleus of the amygdala do
connect visual and auditory stimulus and emotional responses
do we need to be afraid?
what gives context to fears
connection between basolateral nuclei and hippocampal formation
what is the ventral amygdalofugal pathway
basolateral nucleus of amygdala to medial dorsal nucleus of thalamus
what areas have direct connections with the basolateral nucleus
prefrontal, orbital, cingulate, and anterior temporal
what does the central nuclei do
autonomic responses to sensations
where does the central nuclei receive input from
basolateral, solitary, and parabrachial nuclei
where does the central nuclei of the amygdala project
through the ventral amygdalofugal pathway to parasympathetic nuclei in brainstem and reticular formation
what does the cortical nuclei do
emotional response to scents
where does the cortical nuclei send signals
to the lateral and medial hypothalamus by way of the stria terminalis
where do projections from the ventral tegmental area go to
the ventral striatum and amygdala
where do projections from the ventral striatum go to
anterior and medial dorsal nucleus of thalamus
what does the mesolimbic dopaminergic system normally respond to
feeding and reproduction
has a major response to drugs
what can blocking dopamine in the nucleus accumbens do
can reduce addiction
neuroendocrine control
autonomic control
somatic motor control
what is the reticular formation
an interspersed set of nuclei throughout the brainstem
what are the reticular formation nuclei involved in
several reflexive and autonomic responses necessary for survival
reticular formation groups/nuclei
lateral group (parvocellular nuclei)
medial group (gigantocellular nuclei)
median group (raphe nuclei)
pupillary light reflex
associated with pretectal area
vestibulo-ocular reflex
associated with paramedian pontine reticular formation
corneal reflex
associated with facial nucleus
stapedial reflex
associated with facial nucleus
gag reflex
associated with nucleus ambiguus
baroreceptor reflex
associated with ventrolateral medulla/dorsal vagal nucleus
reticular formation motor control actions
licking (hypoglossal nucleus)
chewing (trigem motor nuc)
sucking (facial nuc)
spontaneous facial expression (facial nuc)
swallowing (nuc ambig and dorsal vagal nuc)
vomiting (ventrolateral medulla)
reticular formation regulates
consciousness
gaze centers
posture
habituation
CN IX-XII reflexes
cardiovascular
digestive
respiratory
nociceptive response
