Mid-afternoon. You had a late lunch at Piada
Street Italian (you both had balsamic salads). Carol is on the opening of
Chapter Fifty-Four of David Baldacci’s The Guilty. You have the windows
down and sunroof open while sitting in the shade in the north central section
of Rose Hill Cemetery on this warm partly cloudy day. – Amorella
1530
hours. It has been a good day so far.
Earlier you Kim and the boys had breakfast
at Scrambler Marie’s near Polaris. Paul was called in to the hospital. You had
a good chat with your daughter and the four of you played a sight discovery
game while waiting some time for breakfast. – Amorella
1534
hours. I didn’t know how to express what you just wrote. It is like my mind
becomes congested, somewhat as the nose does – blockage of words – yet you open
the blockage and the words flow quickly and more importantly simply. For one
reason or another the ‘word blockage’ appears almost mechanical rather than
psychological – though this must be an illusion. (I suppose you can shut the
words off the same way you turn them on.) How do you explain this phenomenon,
Amorella? (1543)
I do not view you bio-chemically, boy, and
you are looking for a mechanical reason. Let’s go to Wikipedia, brain first. – Amorella
** **
Human brain [Wikipedia]
The human brain is the main organ of the human nervous
system. It is located in the head, protected by the skull. It has the same
general structure as the brains of other mammals, but with a more developed
cerebral cortex. Large animals such as whales and elephants have larger brains
in absolute terms, but when measured using the encephalization quotient, which
compensates for body size, the quotient for the human brain is almost twice as
large as that of a bottlenose dolphin, and three times as large as that of a
chimpanzee. Much of the size of the human brain comes from the cerebral cortex,
especially the frontal lobes, which are associated with executive functions such
as self-control, planning, reasoning, and abstract thought. The portion of the
cerebral cortex devoted to vision, the visual cortex, is also greatly enlarged
in humans compared to other animals.
The human cerebral cortex is a thick layer of neural tissue that
covers most of the brain. This layer is folded in a way that increases the
amount of surface that can fit into the volume available. The pattern of folds
is similar across individuals, although there are many small variations. The
cortex is divided into four "lobes", called the frontal lobe,
parietal lobe, temporal lobe, and occipital lobe. (Some classification systems
also include a limbic lobe and treat the insular cortex as a lobe.) Within each
lobe are numerous cortical areas, each associated with a particular function,
including vision, motor control, and language. The left and right sides of the
cortex are broadly similar in shape, and most cortical areas are replicated on
both sides. Some areas, though, show strong lateralization, particularly areas
that are involved in language. In most people, the left hemisphere is
"dominant" for language, with the right hemisphere playing only a
minor role. There are other functions, such as spatiotemporal reasoning, for
which the right hemisphere is usually dominant.
Despite being protected by the thick bones of the skull,
suspended in cerebrospinal fluid, and isolated from the bloodstream by the
blood-brain barrier, the human brain is susceptible to damage and disease. The
most common forms of physical damage are closed head injuries such as a blow to
the head, a stroke, or poisoning by a variety of chemicals, which can act as
neurotoxins, such as ethanol alcohol. Infection of the brain, though serious,
is rare because of the biological barriers, which protect it. The human brain
is also susceptible to degenerative disorders, such as Parkinson’s disease,
multiple sclerosis, and Alzheimer’s disease, mostly as the result of aging. A
number of psychiatric conditions, such as schizophrenia and depression, are
thought to be associated with brain dysfunctions, although the nature of such
brain anomalies is not well understood. The brain can also be the site of brain
tumors and these neoplasms can be benign or malignant.
Scientifically,
the techniques that are used to study the human brain differ in important ways
from those that are used to study the brains of other mammals. On the one hand,
invasive techniques such as inserting electrodes into the brain, or disabling
parts of the brain in order to examine the effect on behavior, are used with
non-human species, but for ethical reasons, are generally not performed with
humans. On the other hand, humans are the only subjects who can respond to
complex verbal instructions. Thus, it is often possible to use non-invasive
techniques such as functional neuroimaging or EEG recording more productively
with humans than with non-humans. Furthermore, some of the most important except
in humans. In many cases, human and non-human studies form essential
complements to each other. Individual brain cells (except where tissue samples
are taken for biopsy for suspected brain tumors) can only be studied in
non-humans; complex cognitive tasks can only be studied in humans. Combining
the two sources of information to yield a complete functional understanding of
the human brain is an ongoing challenge for neuroscience . . . .
Executive functions
Executive functions (also known as cognitive control and supervisory
attentional system) is an umbrella term for the management (regulation,
control) of congnitive processes, including working memory, reasoning, task
flexibility, and problem solving as well as planning and execution.
The executive system is a theorized cognitive system in psychology
that controls and manages other cognitive processes, such as executive
functions. The prefrontal areas of the frontal lobe are necessary but not
solely sufficient for carrying out these functions.
Neuroanatomy
Historically, the executive functions have been seen as
regulated by the prefrontal regions of the frontal lobes, but it is still a
matter of ongoing debate if that really is the case. Even though articles on
prefrontal lobe lesions commonly refer to disturbances of executive functions
and vice versa, a review found indications for the sensitivity but not for the
specificity of executive function measures to frontal lobe functioning. This
means that both frontal and non-frontal brain regions are necessary for intact
executive functions. Probably the frontal lobes need to participate in
basically all of the executive functions, but it is not the only brain
structure involved.
Neuroimaging and lesion studies have identified the functions,
which are most often associated with the particular regions of the prefrontal
cortex.
•
The
dorsolateral prefrontal cortex (DLPFC) is involved with "on-line"
processing of information such as integrating different dimensions of cognition
and behaviour. As such, this area has been found to be associated with verbal
and design fluency, ability to maintain and shift set, planning, response
inhibition, working memory, organisational skills, reasoning, problem solving
and abstract thinking
•
The
anterior cingulate cortex (ACC) is involved in emotional drives, experience and
integration. Associated cognitive functions include inhibition of inappropriate
responses, decisionmaking and motivated behaviours. Lesions in this area can
lead to low drive states such as apathy, abulia or akinetic mutism and may also
result in low drive states for such basic needs as food or drink and possibly
decreased interest in social or vocational activities and sex
•
•
The
orbitofrontal cortex (OFC) plays a key role in impulse control, maintenance of
set, monitoring ongoing behaviour and socially appropriate behaviours. The
orbitofrontal cortex also has roles in representing the value of rewards based
on sensory stimuli and evaluating subjective emotional experiences. Lesions can
cause disinhibition, impulsivity, aggressive outbursts, sexual promiscuity and
antisocial behaviour
•
Furthermore, in their review, Alvarez and Emory state that:
"The frontal lobes have multiple connections to cortical, subcortical and
brain stem sites. The basis of "higher-level" cognitive functions
such as inhibition, flexibility of thinking, problem solving, planning, impulse
control, concept formation, abstract thinking, and creativity often arise from
much simpler, "lower-level" forms of cognition and behavior. Thus,
the concept of executive function must be broad enough to include anatomical
structures that represent a diverse and diffuse portion of the central nervous
system."
Hypothesized role
The executive system is thought to be heavily involved in
handling novel situations outside the domain of some of our 'automatic'
psychological processes that could be explained by the reproduction of learned
schemas or set behaviors. Psychologists Don Norman and Tim Shallice have
outlined five types of situations in which routine activation of behavior would
not be sufficient for optimal performance:
1
Those
that involve planning or decision making
2
Those
that involve error correction or troubleshooting
3
Situations
where responses are not well-rehearsed or contain novel sequences of actions
4
Dangerous
or technically difficult situations
5
Situations
that require the overcoming of a strong habitual response or resisting
temptation
A prepotent response is a response for which immediate
reinforcement (positive or negative) is available or has been previously
associated with that response. The executive functions are often invoked when
it is necessary to override these prepotent responses that might otherwise be
automatically elicited by stimuli in the external environment. For example, on
being presented with a potentially rewarding stimulus, such as a tasty piece of
chocolate cake, a person might have the automatic response to take a bite.
However, where such behavior conflicts with internal plans (such as having
decided not to eat chocolate cake while on a diet), the executive functions
might be engaged to inhibit that response.
Although suppression of these prepotent responses is ordinarily
considered adaptive, problems for the development of the individual and the
culture arise when feelings of right and wrong are overridden by cultural
expectations or when creative impulses are overridden by executive inhibitions.
Historical
perspective
Although research into the executive functions and their neural
basis has increased markedly over recent years, the theoretical framework in
which it is situated is not new. In the 1950s, the British psychologist Donald
Broadbent drew a distinction between "automatic" and
"controlled" processes (a distinction characterized more fully by
Shiffrin and Schneider in 1977), and introduced the notion of selective
attention, to which executive functions are closely allied. In 1975, the US
psychologist Michael Posner used the term "cognitive control" in his
book chapter entitled "Attention and cognitive control".
The work of influential researchers such as Michael Posner, Joaquin
Fuster, Tim Shallice and their colleagues in the 1980s (and later Trevor
Robbins, Bob Knight, Don Stuss, and others) laid much of the groundwork for
recent research into executive functions. For example, Posner proposed that
there is a separate "executive" branch of the attentional system,
which is responsible for focusing attention on selected aspects of the
environment. The British neuropsychologist Tim Shallice similarly suggested
that attention is regulated by a "supervisory system", which can
override automatic responses in favour of scheduling behaviour on the basis of
plans or intentions. Throughout this period, a consensus emerged that this
control system is housed in the most anterior portion of the brain, the prefrontal
cortex (PFC).
Psychologist Alan Baddeley had proposed a similar system as part
of his model of working memory and argued that there must be a component (which
he named the "central executive") that allows information to be
manipulated in short-term memory (for example, when doing mental arithmetic).
Development
When studying executive functions, a developmental framework is
helpful because these abilities mature at different rates over time. Some
abilities peak maturation rate in late childhood or adolescence while others'
progress into early adulthood. The brain continues to mature and develop
connections well into adulthood. A person's executive function abilities are
shaped by both physical changes in the brain and by life experiences, in the
classroom and in the world at large. Furthermore, executive functioning
development corresponds to the neurophysiological developments of the growing
brain; as the processing capacity of the frontal lobes and other interconnected
regions increases, the core executive functions emerge. As these functions are
established, they continue to mature, sometimes in spurts, while other, more
complex functions also develop, underscoring the different directions along
which each component might develop.
Early childhood
Inhibitory control and working memory act as basic executive
functions that make it possible for more complex executive functions like
problem-solving to develop. Inhibitory control and working memory are among the
earliest executive functions to appear, with initial signs observed in infants,
7 to 12-months old. Then in the preschool years, children display a spurt in
performance on tasks of inhibition and working memory, usually between the ages
of 3 to 5 years. Also during this time, cognitive flexibility, goal-directed
behavior, and planning begin to develop. Nevertheless, preschool children do
not have fully mature executive functions and continue to make errors related
to these emerging abilities - often not due to the absence of the abilities,
but rather because they lack the awareness to know when and how to use
particular strategies in particular contexts.
Preadolescence
Preadolescent children continue to exhibit certain growth spurts
in executive functions, suggesting that this development does not necessarily
occur in a linear manner, along with the preliminary maturing of particular
functions as well. During preadolescence, children display major increases in
verbal working memory; goal-directed behavior (with a potential spurt around 12
years of age); response inhibition and selective attention; and strategic
planning and organizational skills. Additionally, between the ages of 8 to 10,
cognitive flexibility in particular begins to match adult levels. However,
similar to patterns in childhood development, executive functioning in
preadolescents is limited because they do not reliably apply these executive
functions across multiple contexts as a result of ongoing development of
inhibitory control.
Adolescence
Many executive functions may begin in childhood and
preadolescence, such as inhibitory control. Yet, it is during adolescence when
the different brain systems become better integrated. At this time, youth
implement executive functions, such as inhibitory control, more efficiently and
effectively and improve throughout this time period. Just as inhibitory control
emerges in childhood and improves over time, planning and goal-directed
behavior also demonstrate an extended time course with ongoing growth over
adolescence. Likewise, functions such as attentional control, with a potential
spurt at age 15, along with working memory, continue developing at this stage.
Adulthood
The major change that occurs in the brain in adulthood is the
constant myelination of neurons in the prefrontal cortex. At age 20-29,
executive functioning skills are at their peak, which allows people of this age
to participate in some of the most challenging mental tasks. These skills begin
to decline in later adulthood. Working memory and spatial span are areas where
decline is most readily noted. Cognitive flexibility, however, has a late onset
of impairment and does not usually start declining until around age 70 in
normally functioning adults. Impaired executive functioning has been found to
be the best predictor of functional decline in the elderly.
Models
Top-down inhibitory
control
Aside from facilitatory or amplificatory mechanisms of control,
many authors have argued for inhibitory mechanisms in the domain of response
control, memory, selective attention, theory of mind, emotion regulation, as
well as social emotions such as empathy. A recent review on this topic argues
that active inhibition is a valid concept in some domains of psychology/cognitive
control.
Working memory model
One influential model is Baddeley’s multicomponent model of
working memory, which is composed of a central executive system that regulates
three other subsystems: the phonological loop, which maintains verbal
information; the visuospatial sketchpad, which maintains visual and spatial
information; and the more recently developed episodic buffer that integrates
short-term and long-term memory, holding and manipulating a limited amount of
information from multiple domains in temporal and spatially sequenced episodes.
Supervisory
attentional system (SAS)
Another conceptual model is the supervisory attentional system
(SAS). In this model, contention scheduling is the process where an individual’s
well-established schemas automatically respond to routine situations while
executive functions are used when faced with novel situations. In these new
situations, attentional control will be a crucial element to help generate new
schema, implement these schema, and then assess their accuracy.
Self-regulatory
model
Primarily derived from work examining behavioral inhibition,
Barkley’s self-regulatory model views executive functions as composed of four
main abilities. One element is working memory that allows individuals to resist
interfering information. A second component is the management of emotional
responses in order to achieve goal-directed behaviors. Thirdly, internalization
of self-directed speech is used to control and sustain rule-governed behavior
and to generate plans for problem-solving. Lastly, information is analyzed and
synthesized into new behavioral responses to meet one’s goals. Changing one’s
behavioral response to meet a new goal or modify an objective is a higher-level
skill that requires a fusion of executive functions including self-regulation,
and accessing prior knowledge and experiences.
Problem-solving
model
Yet another model of executive functions is a problem-solving
framework where executive functions is considered a macroconstruct composed of
subfunctions working in different phases to (a) represent a problem, (b) plan
for a solution by selecting and ordering strategies, (c) maintain the
strategies in short-term memory in order to perform them by certain rules, and
then (d) evaluate the results with error detection and error correction.
Lezak’s conceptual
model
One of the most widespread conceptual models on executive
functions is Lezak’s model. This framework proposes four broad domains of
volition, planning, purposive action, and effective performance as working
together to accomplish global executive functioning needs. While this model may
broadly appeal to clinicians and researchers to help identify and assess
certain executive functioning components, it lacks a distinct theoretical basis
and relatively few attempts at validation.
Miller & Cohen's
(2001) model
In 2001, Earl Miller and Jonathan Cohen published their article
'An integrative theory of prefrontal cortex function' in which they argue that
cognitive control is the primary function of the prefrontal cortex (PFC), and
that control is implemented by increasing the gain of sensory or motor neurons that
are engaged by task- or goal-relevant elements of the external environment. In
a key paragraph, they argue:
We assume that the PFC serves a specific function in cognitive
control: the active maintenance of patterns of activity that represent goals
and the means to achieve them. They provide bias signals throughout much of the
rest of the brain, affecting not only visual processes, but also other sensory
modalities, as well as systems responsible for response execution, memory
retrieval, emotional evaluation, etc. The aggregate effect of these bias
signals is to guide the flow of neural activity along pathways that establish
the proper mappings between inputs, internal states, and outputs needed to
perform a given task.
Miller and Cohen draw explicitly upon an earlier theory of
visual attention that conceptualises perception of visual scenes in terms of
competition among multiple representations - such as colors, individuals, or objects.
Selective visual attention acts to 'bias' this competition in favour of certain
selected features or representations. For example, imagine that you are waiting
at a busy train station for a friend who is wearing a red coat. You are able to
selectively narrow the focus of your attention to search for red objects, in
the hope of identifying your friend. Desimone and Duncan argue that the brain
achieves this by selectively increasing the gain of neurons responsive to the
color red, such that output from these neurons is more likely to reach a
downstream processing stage, and, as a consequence, to guide behaviour. According
to Miller and Cohen, this selective attention mechanism is in fact just a
special case of cognitive control - one in which the biasing occurs in the
sensory domain. According to Miller and Cohen's model, the PFC can exert
control over input (sensory) or output (response) neurons, as well as over
assemblies involved in memory, or emotion. Cognitive control is mediated by
reciprocal PFC connectivity with the sensory and motor cortices, and with the limbic
system. Within their approach, thus, the term 'cognitive control' is applied to
any situation where a biasing signal is used to promote task-appropriate
responding, and control thus becomes a crucial component of a wide range of
psychological constructs such as selective attention, error monitoring,
decision-making, memory inhibition, and response inhibition.
Miyake and Friedman’s
model of executive functions
Miyake and Friedman’s theory of executive functions proposes
that there are three aspects of executive functions: updating, inhibition, and
shifting. A cornerstone of this theoretical framework is the understanding that
individual differences in executive functions reflect both unity (i.e., common
EF skills) and diversity of each component (e.g., shifting-specific). In other
words, aspects of updating, inhibition, and shifting are related, yet each
remains a distinct entity. First, updating is defined as the continuous
monitoring and quick addition or deletion of contents within one’s working
memory. Second, inhibition is one’s capacity to supersede responses that are
prepotent in a given situation. Third, shifting is one’s cognitive flexibility
to switch between different tasks or mental states.
Miyake and Friedman also suggest that the current body of
research in executive functions suggest four general conclusions about these
skills. The first conclusion is the unity and diversity aspects of executive
functions. Second, recent studies suggest that much of one’s EF skills are
inherited genetically, as demonstrated in twin studies. Third, clean measures
of executive functions can differentiate between normal and clinical or
regulatory behaviors, such as ADHD. Last, longitudinal studies demonstrate that
EF skills are relatively stable throughout development.
Banich's (2009) "Cascade of control" model
This model integrates theories from other models, and involves a
sequential cascade of brain regions involved in maintaining attentional sets in
order to arrive at a goal. In sequence, the model assumes the involvement of
the posterior dorsolateral prefrontal cortex (DLPFC), the mid-DLPFC, and the
posterior and anterior dorsal ACC.
The cognitive task used in the article is selecting a response
in the Stroop task, among conflicting color and word responses, specifically a
stimulus where the word "green" is printed in red ink. The posterior
DLPFC creates an appropriate attentional set, or rules for the brain to
accomplish the current goal. For the Stroop task, this involves activating the
areas of the brain involved in color perception, and not those involved in word
comprehension. It counteracts biases and irrelevant information, like the fact
that the semantic perception of the word is more salient to most people than
the color in which it is printed.
Next, the mid-DLPFC selects the representation that will fulfill
the goal. The task-relevant information must be separated from other sources of
information in the task. In the example, this means focusing on the ink color
and not the word.
The posterior dorsal anterior congulate cortex (ACC) is next in
the cascade, and it is responsible for response selection. This is where the
decision is made whether you will say green (the written word and the incorrect
answer) or red (the font color and correct answer).
Following the response, the anterior dorsal ACC is involved in
response evaluation, deciding whether you were correct or incorrect. Activity
in this region increases when the probability of an error is higher.
The activity of any of the areas involved in this model depends
on the efficiency of the areas that came before it. If the DLPFC imposes a lot
of control on the response, the ACC will require less activity.
Recent work using individual differences in cognitive style has
shown exciting support for this model. Researchers had participants complete an
auditory version of the Stroop task, in which either the location or semantic
meaning of a directional word had to be attended to. Participants that either
had a strong bias toward spatial or semantic information (different cognitive
styles) were then recruited to participate in the task. As predicted,
participants that has a strong bias toward spatial information had more
difficulty paying attention to the semantic information and elicited increased
electrophysiological activity from the ACC. A similar activity pattern was also
found for participants that had a strong bias toward verbal information when
they tried to attend to spatial information.
Assessment
Assessment of executive functions involves gathering data from
several sources and synthesizing the information to look for trends and
patterns across time and setting. Apart from formal tests, other measures can
be used, such as standardized checklists, observations, interviews, and work
samples. From these, conclusions may be drawn on the use of executive functions.
There are several different kinds of tests (e.g., performance
based, self-report) that measure executive functions across development. These
assessments can serve a diagnostic purpose for a number of clinical
populations.
Experimental
evidence
The executive system has been traditionally quite hard to
define, mainly due to what psychologist Paul W. Burgess calls a lack of
"process-behaviour correspondence". That is, there is no single
behavior that can in itself be tied to executive function, or indeed executive
dysfunction. For example, it is quite obvious what reading-impaired patients
cannot do, but it is not so obvious what exactly executive-impaired patients
might be incapable of.
This is largely due to the nature of the executive system
itself. It is mainly concerned with the dynamic, "online"
co-ordination of cognitive resources, and, hence, its effect can be observed
only by measuring other cognitive processes. In similar manner, it does not
always fully engage outside of real-world situations. As neurologist Antonio
Damasio has reported, a patient with severe day-to-day executive problems may
still pass paper-and-pencil or lab-based tests of executive function.
Theories of the executive system were largely driven by
observations of patients having suffered frontal lobe damage. They exhibited
disorganized actions and strategies for everyday tasks (a group of behaviors
now known as dysexecutive syndrome) although they seemed to perform normally
when clinical or lab-based tests were used to assess more fundamental cognitive
functions such as memory, learning, language, and reasoning. It was
hypothesized that, to explain this unusual behaviour, there must be an
overarching system that co-ordinates other cognitive resources.
Much of the experimental evidence for the neural structures
involved in executive functions comes from laboratory tasks such as the Stroop
task or the Wisconsin Card Sorting Task (WCST). In the Stroop task, for
example, human subjects are asked to name the color that color words are
printed in when the ink color and word meaning often conflict (for example, the
word "RED" in green ink). Executive functions are needed to perform
this task, as the relatively overlearned and automatic behaviour (word reading)
has to be inhibited in favour of a less practiced task - naming the ink color.
Recent functional neuroimaging studies have shown that two parts of the PFC,
the anterior cingulate cortex (ACC) and the dorsolateral prefrontal cortex (DLPFC),
are thought to be particularly important for performing this task. . . .
Bilingualism and
executive functions
A growing body of research demonstrates that bilinguals show
advantages in executive functions, specifically inhibitory control and task
switching. A possible explanation for this is that speaking two languages
requires controlling one's attention and choosing the correct language to
speak. Across development, bilingual infants, children, and elderly show a
bilingual advantage when it comes to executive functioning. Interestingly,
bimodal bilinguals, or people who speak one language and also know sign
language, do not demonstrate this bilingual advantage in executive functioning
tasks. This may be because one is not required to actively inhibit one language
in order to speak the other.
Bilingual individuals also seem to have an advantage in an area
known as conflict processing, which occurs when there are multiple
representations of one particular response (for example, a word in one language
and its translation in the individual’s other language). Specifically, the
lateral prefrontal cortex has been shown to be involved with conflict
processing. . . .
Nonverbal learning
disorder
A nonverbal learning disorder or nonverbal learning
disability (NLD or NVLD) is a neurological disorder characterized
by significantly higher verbal scores and lower performance scores on an IQ
test. People with NLD often have poor motor and visuo-spatial skills. No clear
numbers are available regarding either the prevalence or incidence of the
nonverbal learning disability syndrome. It does appear, however, that the
incidence of NVLD has been on the rise over the past 10 to 15 years.
NLD involves deficits in perception, coordination, socialsation,
non-verbal problem-solving, and understanding of humour.
Symptoms
Non-verbal
communication
People with this disability may misunderstand non-verbal
communications, or they may understand the communications but be unable to
formulate an appropriate response. This can make establishing and maintaining
social contacts difficult. Eye contact can also be difficult for people with
NLD, either because they are uncomfortable with maintaining it (because
processing its input overtaxes their nonverbal cognitive resources and/or
because they are nervous about its sending or receiving inaccurate messages) or
because they do not remember that others expect it. Similarly, knowing when and
how to use physical contact and recognizing emotions in others and expressing
them for oneself can be problematic.
Verbal communication
People with NLD may be described as talking too much and too
quickly, and they may be early readers, good at grammar, and good spellers.
Verbal communication skills are often strong, and people with NLD often rely on
verbal communication as their main method of gathering information and
maintaining social contact with other people. As a result, they often depend on
verbal reasoning skills to compensate in areas where they have deficits. For
example, they may "talk themselves through" a situation involving a
large number of and/or a wide variety of visuo-spatial and/or numerical data.
People with NLD can become confused and feel overwhelmed when the number and
variety of nonverbal stimuli exceed their processing abilities, especially when
those stimuli must be processed in “real time”.
Numerical and
spatial awareness
Arithmetic and mathematics can be very difficult for people with
NLD. Young children with NLD are often seen as brighter than their peers.
However, as these children enter the upper elementary grades or begin middle
school and they are left to handle more tasks on their own, things can rapidly
begin to deteriorate. They can have problems with finding their way,
remembering assignments. They can struggle with math and misunderstand teachers
and peers. They can be accused of being lazy or uncooperative. An NLD person's
math skills are typically several years behind those of their peers. Teachers
and peers are often confused by this because the NLD person has good language
skills.
Many children with NLD often have difficulty with learning
Geometry and acquiring analytical skills to interpret certain information that
is associated with spatial ability.
Motor
People with NLD often have motor difficulties. This can manifest
in their walking and running, which sometimes appear stiff. They may have
difficulty with activities requiring good balance and feel unsteady when
climbing up or down. They may also be more likely to run into things, due to
judging distances poorly. Fine motor skills can also be poor, causing
difficulty with writing, drawing, and tying shoelaces. Those with NLD are often
labeled as "clumsy" or "stiff" by teachers and peers.
Learning a musical instrument such as the guitar and piano can prove to be
especially challenging for children with NLD. Hand–eye coordination, rhythm,
tempo, and visual processing are often involved with learning such instruments
effectively. Athletic involvement is also negatively impacted by the symptoms
of NLD, as several motor skills are required to play many sports.
Co-morbidity
Nonverbal learning disorder has been observed to co-exist with
other learning problems, such as attention deficit hyperactivity disorder (ADHD)
and autism spectrum disorders.
Nonverbal learning disorder is a common co-existing disorder in
people who have ADHD. This tends to make diagnosis for both conditions rather
challenging as it may become difficult to identify the symptoms of each
disorder separately.
NLD can
also occur with other disorders. As with Autism Spectrum Disorders, NLD exists
on a spectrum, and those affected can experience it in a range of ways. Those
with an NLD diagnosis can experience some or all of the symptoms, and to
varying degrees.
Selected
and edited from Wikipedia
** **
Evening.
You have edited what is important from my perspective on your brain activity.
As you read through this material you recognized examples from what you have
witnessed in your own metal processes. In fact you are positive the material
above, much of it, can be found throughout your decades of note taking. –
Amorella
2203
hours. This has taken a couple hours to read through and assimilate these
concepts in memory (no doubt some false memory) of how my brain operates. And,
I have not yet related this specifically to how Wikipedia suggests the mind
works (perhaps it doesn’t). This is enough for tonight though.
You are very interested in seeing yourself
fully in third person, that is, if you could, you would like to study yourself
as a separate person. Do you agree? – Amorella
2208
hours. I would like to understand myself as a separate entity, probably because
I am more comfortable this way. I suppose, if I had a doppelganger I would not
mind being either A (the physical/spiritual reality) or B (the spirited doppelganger). I don’t
think I would really care either way. – rho
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