hello everyone my name is annie reyes
and for this summer dr casey hewitt and i will be your moderators we're pleased
that you could join us for this week lecture in our first seven a week near
known your anatomy meaning series that brings you lectures from experts in the field
covering different anatomy topics each week this series was created by trainees and early
career neuropsychologists to provide free high quality didactic opportunities we would
like to recognize our non-anatomy planning group for their hard work pulling this mini series
off we would also like to thank our sponsors for their financial support for this series before
we start there are disclaimers for the series this training is not meant to replace formal education
in neuropsychology and the views of the speakers are their own questions can be submitted via
the q a box on the lower left of your screen and a recording of today's lecture will
be provided on our website later this week questions will be asked at the end and not during
the lecture today's q a is led by dr casey hewitt and that is my pleasure to introduce dr
catherine price for today's lecture titled frontal lobes anatomy and function dr price
is an associate professor in the department of clinical and health psychology with a joint
appointment in the department of anesthesiology at the university of florida in gainesville she's
a licensed psychologist for board specialty in clinical neuropsychology she is a director
of the preoperative cognitive anesthesia network program for alzheimer's disease and
related dementias her primary research aims are to understand the relative contribution of
white matter versus subcortical great matter structural integrity on the cognitive profiles
of subcortical neurogenetic diseases second her aim is to apply this knowledge towards more
collaborative and longitudinal research examining the predictive value of cognitive profiles
why in great matter structural integrity on one to this disease cognitive decline as well
as vulnerability to accelerated cognitive change after elective medical intervention such as
major elective surgery and it's a pleasure to have dr price giving us a lecture on
executive functions thank you dr price great thank you so very much for this wonderful
introduction and for the invitation i'm really honored i've heard so many wonderful things
i haven't been able to watch this on my own so i am so glad to be able to be a part of it
and now you have a fan i'll be watching all the time so all right so i'm going to do
is i'm going to share my slides here okay can you see the screen okay do you just see the
major screen you don't see the yeah it looks perfect thank you it looks fine okay good all
right so what i'm going to talk about today we're going to talk about executive function um and we
typically talk about executive function we think about the frontal lobes so one thing you're going
to learn is that executive function is not just the frontal lobes but one thing we are going to
ask is i'm going to ask that you at least know the regions of the frontal lobe because this is going
to help you when you are trying to understand executive function and as you're assessing
individuals who may have executive dysfunction so here we go today's discussion i'm
going to orient you to some anatomy we're going to talk about the basic
roles associated with the frontal lobe and then we're going to try a couple of cases for
name that lesion for clinical evaluation okay so first let's talk about anatomical boundaries i'm
going to talk to you about the prefrontal cortex the three major functional areas and we're going
to talk about basal ganglia connections that's the first part all right so first off here now we have
to remember the lateral and the medial side of the brain so we're thinking about um the cortex area
here and here are the main areas i want you to remember you have your motor strip your pre-motor
area and then you have your prefrontal cortex here so this is the lateral side but then there's also
a medial side to the frontal lobe that many of us forget and so i'm glad that we're here to have a
remember to remember that in practice so you have your motor area the pre-motor because you have to
remember the cortex folds in and then you have the medial with your anterior cingulate and then you
have your orbital frontal region so this whole area here hopefully you can see my mouse is the
prefrontal cortex so now i'm going to give you some quiz a quiz um what is this area here that we
talked about so hopefully you're remembering that this is a part of the pre-motor regent okay and
this region is related to responding to stimuli um random stimuli for example this region can be
partially involved in eye movement particularly through electrical impulses and the pre-motor
region here is really important for preparing information from your primary motor cortex and
other functions of the brain it's going to send signals to different areas of your body all
right and it's divided into different parts you have your dorsal you have a ventral part of your
pre-motor cortex you don't need to know all that i just want to make sure that you know that this
area is there it's a very essential part of your your motor function in your frontal lobe and so
we're going to come back to that in a little bit okay so pre-motor cortex now the next
one pretty large we talked about the we talked about this area a minute ago do you
remember what the name of this area is okay well this is the prefrontal cortex all right and in the
prefrontal cortex you this is a very complicated area multiple regions um here as you can see
in this next image this shows you it's a little bit blurry but this is actually not in the human
brain you can see here this is in a monkey brain and there are different areas here that are cyto
architecturally distinct based on cellular layers as well as different functional regions that
you'll know from broadening on broadman's area so you're going to know the prefrontal cortex is
complicated because it actually includes multiple regions you have your orbital frontal region and
that orbital frontal region is here you can see right here it's this is from the side this is from
your ventral view and this is from your mesial view all right um so you're going to want to pay
attention to this region we're going to talk about this region as well it's part of the prefrontal
cortex that's the orbital frontal specific area of the prefrontal cortex and then here's another
area of the prefrontal cortex you need to remember and what area would this be so i want you to think
about that particularly if you're a student or a trainee uh to remember what structure this could
be because remember we talked about you have the singular cortex you've got this is on your
mesial area so this would be your medial prefrontal cortex in the middle of the brain
slicing right in the half and you're looking on either side okay and the inside of the hemisphere
so this is where the cortex is folding in you might have remembered from when you studied the
homunculus from your sensory and the motor system you can tell a lot you have to think about the
homunculus running across right right through um providing you with your boundaries of what areas
and what type of the body is being stimulated within different areas we're going to talk about
that in a second later on in the in the talk i'm going to show you a slide that actually will give
you some nice lesion detection okay so what about um this last area this is really fascinating for
one reason well multiple reasons but let me back up these regions here the orbital frontal are very
cyto architecturally cellular this distinctly uh unique there are different areas here area
frogmen 10 and 11 that are associated here um that i want you to remember um overlap with
a lot of key sensories or over to frontal etc and then here when we get back to the dorsolateral
prefrontal region this has a number of different areas here that are not primarily based on
your cytoarchitectural or cellular layers this is your dorsolateral prefrontal cortex and
even though it has this nice blue blob on top here right this light this area of the cortex
is functionally defined whereas the other two are defined by cellular layers and you can
actually see distinctly distinct differences in the cortex in the frontal cortex
associated with those regions of interest but for the dorsolateral prefrontal cortex which
is this structure here is functionally defined which makes it really unique it's actually
very interesting and challenging to study the dorsolateral prefrontal cortex because it's
it's individualized based on that on that person so it's been identified with functional resting
state or functional studies task based oriented studies and you'll see that the dorsolateral
prefrontal cortex is actually different for everybody other things that are interesting
is that it's really challenging um to uh do a to segment that area using different types of
software if you've ever tried to use free surfer versus other tools you'll see that it'll actually
extract different areas and different sizes of the dorsolateral prefrontal cortex so there's lots
of challenges and interesting elements within these different regions of the brain you can
see how complex the prefrontal regions are all right so those are that's just the basic
very basic elements of some of the key regions as neuropsychologists we assess within the frontal
lobe okay now i'm going to come back to those regions but i also want you to realize that those
structures those cortical structures are connected to important subcortical structures and also
specific white matter circuits all right and this is you're going to understand this in a
minute so hopefully this is a bit of a review all right so there are five components of the basal
ganglia as well as the thalamus that you need to remember when you're thinking of the frontal
lobes all right and the reason why is because the frontal lobe is connected to these structures
these five components all right you've got the caudate nuclei the putamen the globus pallidus the
subthalamic nucleus and the substantia [ __ ] okay now the caudate and putamen combine to make the
striatum the putamen and the globus pallidus form the lenticular lentiform nucleus but it
looks just like a lens and then the caudate putamen of the globus powders make the corpus
striatum so here's a nice uh depiction of this and you have to think about more of a vertical
you have to think about the vertical aspect of the brain right and the connections between
each of these regions here is another depiction of this relative to the frontal lobe i like to say
here this is your coronal slice like you're taking a slice here and you're looking in this slice
you're looking this is axial slice so you're taking a slice here and you're looking down all
right so here now you can see that you have your caudate nucleus and the putamen here forming
your striatum all right these two areas here then you have your the ventral lateral nucleus of
the thalamus here and you have your subthalamic nucleus your globus pallidus and substantia
[ __ ] now key among here you have your um you have gada gaba you have glutamine you have
major neurotransmitters but you also have quite a bit of impact from your dopamine acetylcholine
and your serotonergic neurotransmitters and what's happening is that these are providing an input and
pathway for activation within the frontal lobe and vice versa and they're going through these white
matter fibers here so you can see this connection going from the from these structures these
gray matter structures these nuclei the cells here all the way to the external areas of the
cortex through these white matter fibers that are crossing one another right sending information
back and forth so we have to appreciate this loop and through work of alexander on the long and
strict which you can breed and you know this very well of where you are in emory all of
their wonderful circuits that were published approximately what now 50 years ago that's really
sad um there's been so much work since then but what we still know based on this classic work
is that there are three neuroanatomical loops and two motors okay and you can there there's been
debate as to whether there are other ones but i really want you to remember if you are going to
be a neuropsychologist involved in neuropsychology involved in neurology you have to remember there
are three neurobehavioral circuits all right and the basic pathway is the same this is really
important because what what happens behaviorally is that you can have a lesion in the cortical
area for example a broadband area 10 or 11 and you could present with a certain pattern if you have
gut lesion in the striatum you could show the same pattern you could have a lesion here you might
show the same pattern so you have to see there's duplication among this among this loop okay
so i'm just checking the chat to make sure okay that i'm not missing something okay so
for the orbital frontal cortex we're going to start from in a hierarchy we're going to start
at the start of the orbit of frontal region all right and you have to think of there's
connection for everybody right back up and back up one side i want you to remember
there's a connection from the cortical to the striatum to the pelvis to the thalamic
regions and all right going back sorry that arrow should be the other way but um one thing
that differentiates the different regions of the brain is where in the striatum the cortex
is connecting okay so pay attention to that so if you look here at the orbital frontal
cortex it goes from the cortical basal um uh broaden areas 10 and 11 to the striatum
it's going to the lateral eventual medial caudate when you start to see ventral regions you start
to realize okay ventral is actually this is really interesting ventral is getting information that is
relaying information more about olympic responses the vagus nerve is there pain responses are
in the cottage okay uh in that area um and then also ventral star adam so if we think
about orbital frontal when you're going to learn about the orbital frontal is that
the orbital frontal region is involved in your a lot of your olympic responses so this makes
sense that it's going to this cortical to the striatal then going to the palatal with the globus
pallidus internal and substantia [ __ ] cars um particulata and then the thalamus okay and
then back so uh-oh if we i have to take this off so if you think about this what happens is
when this is involved in our personality our mood and then you're going to hear a term called
utilization behavior that i'm going to show you so this is just showing you how this this
loop is involved in different types of uh frontal functions typically what we associate with
personality okay so that's just a little taste of what we're going to talk about now the next area
that i want you to think about because remember we're focusing on the prefrontal cortex all right
so the next year i want you to think of is the mesiora the medial region of the frontal
lobe where i showed you earlier okay so this area we're still in the pre-motor area but
this is now mesial and now it's connecting to the ventral portion of the striatum again but you also
have involvement um with the putamen and you have the nucleus accumbens um and then it's going to
the paladin and then it's going to the thalamus so here what you often see here is you see a
disruption in motivation you see disruption and attention you can see some apathy you can see
slowness and i'm going to show you a little bit more we're going to talk about this more this
is just a taste of what we're going to talk about then the next one the next day remember
how i talked about this was a functional area of the frontal lobe this is the dorsolateral
region of the the cortex of the frontal lobe this one you again have you have this area
classically we consider area 46 involved and it goes to the dorsal lateral caudate head
now remember i showed you earlier how the orbital frontal circuit and the mesial went to the
ventral striatum this one's going to the dorsal area of them sorry dorsal area of the striatum
and specifically the dorsal portion of the caudate what we've learned through research is that the
caudate is also segmented in numerous different areas and where the projection systems are coming
in can tell us a lot so what we know is that the caudate the dorsal portion of caudate actually is
really important in more of the cognitive aspects of function whereas eventual like i said is more
involved in more of the visceral pain fatigue nausea those aspects so you want to think about
where the input and the output systems are within the structures okay hold on one second we
take this one away too all right so now we're back so typically when we think about
damage to the dorsolateral prefrontal cortex we're thinking about that's the area involved in
executive dysfunctions what we typically call um damage to this area but i want you to think a
little bit more critically about this and i want you to think about really what is executive
dysfunction is executive dysfunction really aligned only to the dorsolateral prefrontal region
so we're going to talk about that too in a few minutes reason why it's typically associated with
executive dysfunction is because individuals who have damage to the dorsolateral region typically
those are individuals who are having difficulty searching for different types of information
they might have make source memory errors they have difficulty with working memory maintaining
clear output you're going to see some hyperkinetic behaviors i'm going to give you some examples
of it may be more stimulus bound um and it's just like things jump out and they want to grab
them so i'm going to show you a bit of that too all right so the next slide now so
that was just basic basic basic anatomy with regard to frontal lobe um areas and their
connections to the basal ganglia and the circuits or the three parallel circuits and the one thing
i do want you to remember though the takeaway message from that is that those cortical regions
are connecting to specific areas and specific um structures within that basal ganglia network
and within specific areas of the thalamus and that there's that lovely beautiful parallel
circuit and that you can have a lesion in any area of those circuits that can produce a very similar
behavior all right so we may think that a behavior is portable but it actually might turn out that
it's a lesion within the thalamus all right in a specific area of the thalamus some wonderful
work by bruce crossin who was at emory he was at uf too he showed that with language over and
over so if you need to if you're interested in that i encourage you to read some of his
books and some of his work specifically about um the subcortical uh structures and language
it's a really great great textbook um a lot of his research so now let's talk about
the functional goals okay of the frontal lobe i'm going to talk about the framework its role
in motor output and we're going to just talk about basic definitions and then i'm going to go
back over again the functions of those prefrontal regions and what happens if you have a damage okay
and then we're going to try two clinical cases oops oops let me back up i hit the end button when
i didn't mean to hit the end button so here we are there thank you okay so here we go this slide
is one of my favorites this is about frontal lobe and this is this conceptual framework now
i want you to we're going to change the word function from frontal lobe function i want you to
think of the frontal lobe as a mediator all right what does mediator mean mediator is a person
who's in between two types of opposing forces and trying to help create something or some agreement
between two types of forces is basically what the frontal lobe is doing all right it's a mediator
so look at this figure this is a lovely figure um and this shows you let's check them from
the bottom this is your environment the frontal lobe is the mediator between the environment and
the rest of the body basically okay and it's in you have to remember that half your
brain is sensory the other half is motor you're this in your frontal lobe is your biggest
low right it really is huge so what's happening here is you have to humans which is actually
really interesting humans um have one of the largest um frontal lobes okay um and what do we
do what is one of the biggest things that we do humans we create we are um known for creating we
have created uh buildings right everything you have we created we created tools right so and we
have thumbs so we've actually we have used things to change our entire world and i'm able to talk
to you wherever you are through the power of zoom right and that was created by humans that's
because we take the environment and we change it right so that's exactly what the frontal
lobes haven't allowed us to do so we have the environment information comes in to our primary
sensory areas then our hessial's gyrus think about it our occipital regions our sensory tactilely
our frontal lobes take that primary information and they it goes from primary sensory whatever
that area is here goes to our unimodal association cortex to figure out what it is right then
it goes to okay now let's figure out on multiple information about that object then our
prefrontal lobe takes that information and knows what to do with it and then we make a decision
somehow that we're going to use this object in some certain way or we hear something
and so we're going to respond this way and then we create from that standpoint we make a
rule that oh now i want to do x or now we want to do y and so then we produce it so that's what the
frontal lobes have done they take the information the sentry in and they create it and reproduce
right so now you have to consider it that as a mediator so there's no direct syntactic input
right or output from the external environment it comes through the sensory and it comes
through the olympic system our emotions also and then we produce an output and that's
the motor behavior and it's linked exclusively through the cortex and subcortical
regions so it is really is a mediator okay um and it's a dispersed neural network such that
you have to think about the fact that um it's not only just a frontal to the subcortical structures
that i showed you but the frontal to the parietal regions all right and i didn't even show you those
networks but you can see it here the pictures you have your longitudinal particularly that are
going back and forth between your frontal parietal and you know now that working memory is frontal
and parietal right so we no longer really think of it just as a frontal lobe so as you go through you
have to apply the frontal lobe function then to cognition behavior and you have to remember that
your higher order thinking right is fused to this whole entire biological drive of what you see in
the environment right so when you think about how a person is um engaging on the environment if
they're able to you have to kind of think of the best way to tell you um it's not it's your
responsiveness to the environment how well you how a person is experiencing the environment and
then their ability to take that information and create something from the environment and change
their output or respond appropriately so it fuses higher order thinking fuses the biological
drive with an external behavior okay all right and then you have to think that
the frontal lobe is also helping to regulate that behavior what is it appropriate is it not to
change the environment in a certain way so there's always this give and take right between your what
you see your internal drives and what you produce um and so the result is a really nicely
you know hopefully a goal-directed behavior where a person is able to balance
those effective things that are coming through not only the
orbit of frontal region sorry someone had to say something no something is
coming information is coming through all the different areas of the brain but then there's
also the orbital frontal region you have to think about the mesial region you're going to
see this a little bit more as we talk about it and then there's the planning component so
all different areas of the prefrontal lobes are engaged together as with the whole
brain i hope this is making sense okay so in general the main message here is that the
executive function is a function rather than a brain region so don't think when you're doing your
assessments or you're working with individuals that if there is executive dysfunction that it's
primarily in the frontal lobes where the lesions located okay the frontal lobe is a contribute is
contributing but it's part of a wider network of brain involvement okay so now we're going to
go back and we're going to use this i want you to look at this picture over here to the left
we have the the figure and i want you to think about the regions that we talked about from this
from the um when we talked about the anatomical pathways to help you understand the behaviors
that you see with individuals or with behaviors typically associated with the prefrontal
cortex and specifically the orbital frontal or prefrontal cortex so here when we think
about the orbital prefrontal cortex what we found through different um stimulation uh studies
through lesion studies through animal studies case studies we found that individuals when there
is a damaged or we found that the orbital frontal cortex is really important for uh understanding
and being able to engage on the environment uh with regard to their internal drives
being being able to use your internal information and your internal drives to enact
on the entire on the external environment so there's planning with regard to your intrinsic
factors there's also a reward and emotional value of stimuli which is highly connected to your
amygdala and the connections between the orbital frontal cortex to the amygdala the orbital frontal
cortex is really important for your ability to moderate your drives and appetites it's involved
in social behavior and it we really think of it with regard to our personality and you
probably remember some very famous cases about individuals who might have had a lesion
to an area of the orbit of frontal cortex and have had drastic changes in personality
and i bet you can name one off the top of your head which would be phineas gage and
so you could think of that that individual and if you do then you might remember that when
you have damage to the orbital frontal cortex that's when you start to see
some of these behaviors so clinically you're going to look for these
behaviors here first you might look for reduced decision-making ability or being overly
impulsive okay um you might see poor social skills so uh whistle suits which is a inappropriate
chocularity or laughing right um maybe euphoria inappropriate sexual advances poor impulse
control or sense of self you might see some disinhibition acting impulsively grabbing
things there's been some classic stories of individuals putting out glasses and people uh
the patient or the individual who's being assessed might pick up the glasses and even though that
individual has their own pair of glasses on they put their the other glasses that are on
the table right on top of their own glasses all different types of observations i'm
going to give you an example in a minute then you might see emotional ability you might see
that sometimes they're happy sometimes they're sad aggressiveness reduce self-awareness so
that's typically what we associate with personality changes now how would you assess
orbit of frontal function what do you do and that's a really good question and i wish
i could have it as a group discussion but in general you know there's some wonderful papers
out there and one i would love you to look at is as a some there are some classic papers um from
lermy that were published on case observations actually observation is probably the
best thing you could do as a clinician for observing and understanding orbital frontal
behavior so you're watching an individual you're a behaviorist okay so in um larry's papers this
is one and this is called utilization behavior and so he has some wonderful papers where
he had three different cases that who had different areas of brain damage and he does a
lovely review of all the areas of the brain that were damaged in the separate papers but in one
paper he summarizes the patients um that he saw and it wouldn't be irb approved today but actually
what he did is he put out different situations he brought in this wonderful woman here and he set
up different stations for her so for example he took her into the kitchen and there were dishes
there that were dirty in the sink and he just let her be and watched her and she went over there
proceeded to go ahead and clean the dishes and put the dishes away right um in another example he
had brought her into i think um into the bedroom and there had been some needles out there or
sewing kit and she had gone ahead and she had begun to she just picked it up and started sewing
and fixing and another more drastic approach she actually had a syringe out and uh she told him
she filled up the syringe with the fluid there and said told him that she would give him the shot so
that was a very clear one uh very interesting case reports now he has a two other cases that he talks
about but it's these are very extreme cases of utilization behavior but they did have uh damage
within the orbital frontal regions of the brain as well as the dorsal so observation is clearly
one way in which you can assess orbital frontal function other ones is you can use tools such as
the iowa gambling task where you can really pull on that internal drive response you can see
how a person responds uh to external stimuli based on it can they actually make a decision
that is going to be useful for them how with regard to do they change their environment
and their choose so i would suggest that you look at the iowa gaming task or other tools if you
want to assess orbital frontal behave behavior but also the best approach is
using your own observation skills okay so what about the medial frontal
or the sing or the singular region all right so this structure is involved like
we said again in your initiation and your action and your emotional expression okay
so here when we think about this structure um this is an area of the brain where you're
getting you have this is where you know back here when we're talking about the orbital
frontal regions there is a reduced capacity to use internal stimuli to guide behavior
based on an external stimulus okay here we're talking about the medial or mesial region
this is when there's a lack of internal drive all right and this is more of an endogenous versus
an exogenous when we see endogenous it means internally driven exogenous is more externally
so um this is the ability to initiate and sustain your interest or your movement all right very
clear connections to the basal ganglia structure and we often see in this structure truly
engaged in a number of different disorders and i'm sure you can think of some on your
own that might have that you can classically think of would be associated with disruption
to this structure air or the whole pathway so these individuals would not engage as
much on their environment you could put out eyeglasses for them they wouldn't pick them up
all right you could try to get them to engaged um to move to a certain area of the room they're
not interested even watching television they may not be interested or maybe they sit and watch
television all day and they don't do anything so individuals with this structure they typically
are damaged to the structure or anywhere along that circuit that i mentioned before they might
show uh signs of akinesia which means a is loss right when you have the a preface loss of
movement all right or loss of inability for movement of speech of um any physical
movement at all uh they may have a bilia apathy action so limited emotional expression
limited social activity and one of the classic classic diseases that we typically associate
with medial frontal involvement or disruption in that in circuit here this circuit here
we typically think of would be parkinson's disease if you haven't thought of it yet okay
some measures that you could use to assess medial frontal functions you can look at apathy
measurements which is different from depression you could use different scales you
could use your behavioral observations and also caregiver reports uh reduced initiation
for goal directed behavior impaired activities of daily living just not cleaning taking
care of themselves you can see this type of behavior in individuals who are remarkably
depressed okay all right so now let's contrast those two regions to the dorsolateral prefrontal
region right so the dorsolateral prefrontal region as we know is a very large region okay
we talked about the different areas of the dorsolateral prefrontal region and this
area is involved in the planning component being able to use external information as well as
combining internal to navigate and manipulate the environment now this is where you are processing
information online actively so working memory is involved spatial maintaining information in your
mind multiple types of information mind whether it be spatial verbal internal modulation as well
as external modulation engagement of both the internal and external drives
that are there so this is very very complex possibly why it has such a very large
area that we think of in the prefrontal cortex it also like i says i said has connections to the
subcortical structures but also to the parietal regions very much involved in your sensory
awareness and your awareness of your whole uh space okay um we typically think of it with
regard to working memory so we think about um an individual you know doing two things at
the same time we think about disinhibition of being able to inhibit immediate responses think
about attentional control here are some examples so for example if i ask somebody i want
you to draw two a three two three two three two three two three and i kept pushing
that person right and here's their output a two a three a two a three and they keep going but
then they lose set they begin to lose their focus lose their attention they may get distracted due
to internal or external reasons and here you see a perseveration here okay so this is an example
it's actually a alex it's a test um based off uh alexander luria um some of his work and so
that is an example of a loss of set that would be associated with dorsolateral prefrontal
disruption another one is you've probably seen is the stroop effect so for example where you have
to see different colors and you name the colors and then you read the word but then you have
to name the color ink and not read the word so you're having to inhibit all right and so
this is the stroke effect this has been linked to also the dorsolateral prefrontal cortex all
right and the circuitry area another example we did remember i talked to you about being able
to the ability to be able to stop behaviors um uh recognize when there is any type of modulation
or disruption in a person's output and being able to modulate their own output that would be linked
to dorsolateral prefrontal region disruption here are some examples this is also from luria
this is called hyperkinetic behavior you can see this here these are some examples from
his books um so here's repeating the circles you can see perseverations here this is
hyperkinetic behavior and you'll see this on different types of drawings that you might
be doing with your participant or your patients other areas associated or disruptions associated
with dorsolateral prefrontal cortex it would be planning an organization one of my favorite tests
is a clock drawing test and here you can see that this is a test where you would say you
have them do a command and a copy condition and the instructions are i want you to draw the
face of the clock put in all the numbers and set the hands to 10 after 11. so if i'd had this you
probably would have seen i've had this in real time you would have seen the person probably draw
a clock a circle sorry circle um they may have put in the numbers but here you can see the numbers
are a bit disorganized just a bit um it's over here is where they have the 12 and the 11 10 and
then the one is on top of the two and then you can see that there is some difficulty with the place
in the hands and they're connecting the hands with a line going across with the different numbers
so the planning and organization is not there at least from the command and the production of
that clock themselves without an external stimulus you give them an external stimulus like a copy
you can see that they improve they still have some errors but they did improve so there was
a response to an external stimulus so this is internally driven and this is externally
driven and you can see that there is still a little bit of an error here with the external
driven and this individual actually did have a type of disorder involving the region
of the dorsolateral prefrontal cortex but providing a comparison between
internally driven and externally mediated or external um stimulus for modeling can
give you a really nice insight as to whether or not as to the type of behavior a person is
or a type of impairment a person might have and where in the brain it can be all right so
individuals who have dorsolateral frontal damage they you might see perseveration you might see
reduced word fluency loss of output you might see difficulties with working memory like we
mentioned disinhibition using hyperkinetic behavior or poor planning so there are a number
of things that you could see with dorsolateral regions damage all right so clinical presentations
i'm just going to give you a couple of examples in a minute but first let me just
remind you you know that the human uh in humans the prefrontal cortex occupies about 35
of the neocortex just like i had told you before it's huge for us right um but it is the newest
area of the vortex and it's the latest to grow uh last to grow first to be lost um and you
know we have to remember that it's one of the it's still growing through your teen years and so
these are things to consider um and it's different with regard to other animals so it's our largest
lobe and it's like i said a mediator now when we think about damage to those disorders not only do
we have to think about the age of the individual etc but we have to think about all right um what
areas and what structures are involved is it the cortex could it be the subcortical could it be
neurotransmitter based only could it be white matter structures etc and so there are a number
of case number of disorders uh that you might see difficulties with the frontal
lobes frontal temporal dementia you can see traumatic brain injury frontal lobe
epilepsy attention deficit disorder schizophrenia parkinson's disease you could see stroke and
this is a this is from the bloominfeld text with neuroanatomy through clinical cases and i'm
sure you remember the anterior cerebral artery the middle and the posterior artery have different um
regions that they occupy and provide for fusion to so you could have a damage to these and
it could just uh differentially disrupt the frontal lobes from here so you have to
think that the frontal lobes really are quite wonderful they provide us with an incredible um source of behavior but really complex for
us um let me give you a couple of examples here so this is a an individual who's 64 years
old he was referred for a neuropsychological evaluation by his neurologist so his presenting
symptoms included increased use of pornography increased spending of money multiple affairs no
longer working due to difficulties he was brought in for a neuropsychological eval like i said by
his neurologist because they they really wanted to rule out what could be some of the difficulties
what could be some of the differential diagnoses they had um i actually saw him he was eating
i had to go see him um at a at a clinic and he had brought in food and was repeatedly
eating uh pulling out things out of his bag when we did the assessment he had an impairment
in working memory recent memory he was having difficulty with set shifting disorganized uh
disinhibited he was having some difficulty with word retrieval um now he had progressed a bit
i guess you would say i'm probably giving you a little bit of an idea of what kind of ex what
kind of disorder he is um but he um uh really was doing fine attentionally and processing
speed wise he was walking his gait was fine and he was denying any symptoms of
anxiety or depression so for him he actually was diagnosed with what's called
a frontotemporal dementia behavioral variant based on his primary symptoms which included the
orbit of frontal classic behaviors and he also was having just a progression of the disease so that
it involved more of a cognitive symptoms involving now involvement of the dorsolateral prefrontal
cortex as well as some of his temporal regions so just due to time i'm going to skip
to the next one this is mr m he's a 58 year old man who had come in now he was really
interesting he was observed in the waiting room he was hunched over and he's sad he had
limited expression during discussions he had um adequate grooming but was slow slow to
initiate slow to move somewhat lethargic now here on some testing here's his
processing speed measures this is just a t score i'm sorry that they're not all z scores um
but this is a t score remember high is good hit this i saw him actually twice these aren't the
real dates this is um just put in automatically but here's the average average is up here at 50.
here are his scores on trails a stroop test troop color test and you can see that um he's pretty
um this is before and this was the second um time i saw him i guess a year later yes so here is
he's going a little bit up and down but in general you can see he has a trend towards reducing in his
inhibitory functions all right and just processing speed just slightly here's his attention in
working memory digit span forwards forward span backward span and letter number sequencing um
and you can see they're pretty they're maintaining um slightly lower over the year but still
within low average to average although backwards fan and working memory certainly
are reduced at that time point particularly both across both ears and here's in his inhibitory
and problem solving same pattern now when we get to his depression anxiety and apathy you can
see here here's his anxiety higher is bad right and his back depression inventory and
geriatric depression scale really high across each of the time points that he's been followed and you
can see that here uh moderate to severe depression for him so he was actually diagnosed with um he's
just been maintained as intractable depression and so his area would that you would associate
with frontal function would be more on the mesial whereas the first case that i showed you would be
more orbital frontal all right so overall today this was just a brief discussion of the basic
frontal regions of the of the brain how they connect subcortically to remember that the frontal
lobe is a mediator it's in uh it's its goal is to help us to regulate our internal drives with the
environment and to help us produce and act on the environment all right i also went over two basic
clinical cases now the one thing i really want you to do is just to keep reading read on the frontal
lobes there are so many wonderful books out there on the frontal lobes i just encourage you to
do that and like i said just remember it's a mediator for behavioral profiles and i want to
thank you so much for letting me be here today thank you dr price we really appreciate
the talk that he gave us today so informative i think something too is we've
had so many q and a's in today for our lecture i would like to say there's so many on here so we'll
start off with some of the fun ones you ended with case presentations which i think is great in
all of training so for this one they wanted to thank you for providing the case examples
but then when working with people with frontal lobe dysfunction and formal frontal disorders do
they realize something is wrong for example when drawing a clock are they able to see the clock is
drawn incorrectly oh that's a great question so sometimes many times individuals are not able
to provide you with feedback that what they notice is any that anything is wrong um and
so that's a really interesting observation it's a really great question in in
your clinical work what do you do do you point it out to them that it is
incorrect or do you ask them to compare no typically not that's a great question so you
are taking that information in and you move on to the next task at that point so for example i'd
say well do you see that this is can you tell me do you think this is a an accurate drawing of the
clock and you wait to see what they say then you would give a copy condition see how they do on
the copy or you move on to the next task to get more updates today together exactly i think it
speaks to not just do our tests give us so much information but also behavioral observations that
can be very important for the feedback session thank you i agree so i think another question we
have here is can you speak more to the connections between the cerebellum and the frontal lobe oh
that's a great question oh my gosh the cerebellum choose a frontal lobe so there's cerebellum has
been so underappreciated with regard to executive function and behavioral output um so we have
to remember processing speed elements are also involved with cerebellar we know that there are
celeb cerebellar regions involved in planning um so you know you do have to think about that
but also from a neurotransmitter standpoint um you have to remember that that
significant amount of dopamine impulse and then also you have um regions
associated with acetylcholine production so um there's some wonderful work i'm sure as you know
um being done on the cerebellum with regard to executive function um it's just an area that you
have to be aware of and you have to appreciate uh i'm trying to think anybody else can chime in with
regard to structure is just something you have to you have to be aware of and read the literature
and know that that is it's a whole brain system understood i think that's the whole point too
this lecture is trying to understand it's a whole brain system and it's hard to break
it down sometimes we really appreciate you trying to talk to us i felt like for me
personally i thought you were personally giving me a lecture today and i wanted
to chime in sometimes but with this too you speak to that it may be difficult to
learn about all the different structures what are some of the best resources that you
give students to start learning all of this information ah one of the best resources okay so
a reading lease resource or a reading resource or sure um okay above dr price yeah i'm trying to
think um so one of some of the best resources i would encourage you to read colbin wishaw text
is awesome uh also of course the lesac text those are um perfect but i really always go
back to coleman wish off those texts are it's just perfect and they have numerous iterations
now i'm not i don't have the most recent version but i encourage everyone i i always go back to
the one that my first one it's just fabulous yeah i think it's great too using those resources
we talked a little bit about feedback before so some people had some feedback questions with this
if somebody does have a frontal lobe disorder how do you explain it to them in a feedback session
oh that's a great question well um very carefully and i love feedback sessions typically i what i
do when i'm discussing things i try to make it more simple for me i do a lot of drawings i
like to make it i try to talk about the brain in a very simple way so for example one of
my approaches is i talk about the brain as an apple so i'll say you know how we have
an apple apple is a can visualize an apple and i'll talk to them about okay so the apple
has an outside you have your skin of the apple and then you you know if you cut the apple in half
then you have you have the core you also see the white and you have the seeds and so the outside
of the apple the skin is just like the cortex and then you have the the core of the apple if
you can visualize cutting it in half that is your uh those are your ventricles right so that's
your your the core then you have the seeds those are your subcortical nuclei and then you have the
whites we'll actually will draw that out for them and then we can have a discussion about what
the white does the white is those are white matter fibers and those are connecting the
seeds to the skin and sending information back and forth and then we talk about it we draw
and then i talk about the different areas of the brain and the behaviors and kind of link it back
to the drawing you have to be very concrete um and uh give information in a very kind um
careful manner and then but make it so it has value and so that they understand how that impacts
their life and link it back to what they're also indicating what their complaints are so it has
to be a give and take between you the information that you have as well as with the um the patient
themselves or the client it's a great way of looking at it it has to be very interactive
and it's very interactive do that definitely patient quality of life yeah provide something
for them yes i'm gonna i'm gonna have to steal the apple description yeah please do drawing
skills for that one definitely appreciate your time dr price we love the information that
you gave us today and i would like to do a shout out for next week as well so next monday
august 23rd we will have mary pat mcandrews from university of toronto presenting on learning the
memory so we look forward to everybody joining us next week thank you again dr president thanks
so much take care everyone bye-bye stay well you