The contralateral organization of the forebrain (Latin: contra‚ against; latus‚ side; lateral‚ sided) is the property that the hemispheres of the cerebrum and the thalamus
represent mainly the contralateral side of the body. Consequently, the
left side of the forebrain mostly represents the right side of the body,
and the right side of the brain primarily represents the left side of
the body. The contralateral organization involves both executive and
sensory functions (e.g., a left-sided brain lesion may cause a right-sided hemiplegia). The contralateral organization is only present in vertebrates.
According to the current theory, the forebrain is twisted about the long axis of the body, so that not only the left and right sides, but also dorsal and ventral sides, are interchanged.
Anatomy
Some afferent decussations.Pyramidal decussations.
Two of the cranial nerves show chiasmas: (1) the chiasm of the optic tract (i.e., cranial nerve II), which originates from the eyes and inserts on the optic tectum of the midbrain; and (2) the trochlear nerve
(i.e., cranial nerve IV), which originates in the ventral midbrain and
innervates one of the six muscles that rotate the eye (i.e., the superior oblique muscle).
Although
the forebrain of all vertebrates shows a contralateral organization,
this contralaterality is by no means complete. Some of these exceptions
are worth mentioning:
Olfaction (i.e., smelling sense) is a noteworthy exception. Each olfactory lobe connects to the ipsilateral centers of the frontal cerebrum.
In chondrichthyans (e.g., sharks and skates), the thalamus does not retrieve a branch from the optic tract but only from the contralateral optic tectum, so that the optic path decussates twice, and the forebrain represents the ipsilateral eye.
Most afferent and efferent
connections of the forebrain have bilateral components, especially
outside the primary sensory and motor regions. As a result, a hemiplegia
that is acquired at very young age can sometimes be completely
compensated over time.
According to current understanding, the contralateral organization is due to an axial twist (explained below). A number of other explanations have been published, the most popular of which is the visual map theory (explained below). A short review of existing hypotheses is given by reference. A popular-science video explains these theories in brief.
The Visual Map Theory and the Axial Twist Theory have been formulated in detail and can be regarded as scientific theories, and are explained in detail below.
Other hypotheses tend to explain specific aspects of the
phenomenon. One proposes that crossing generally provides better
geometrical mapping. According to another view, the crossing is a coincidence that has been conserved by parcellation. A third hypothesis proposes that the crossing results directly from optical inversion on the retina of the eye.
An old notion, first worked out by Jacques Loeb, is that the contralateral organisation might have an advantage for motor control,
but simulations by Valentino Braitenberg have shown that both ipsi- and contralateral connections are of major importance for control.
Further studies have asked if there is a topological
or functional advantage of the decussations.
Visual map theory by Cajal
Cajal's
schema of the visual map theory. O=Optic chiasm; C=Visual (and motor)
cortex; M, S=Decussating pathways; R, G: Sensory nerves, motor ganglia.
Social and behavior change communication
From Wikipedia, the free encyclopedia
SBCC by health practitionerSBCC on the Development-Entertainment spectrum.
Social and behavior change communication (SBCC), often also only "BCC" or "Communication for Development (C4D)" is an interactive process of any intervention with individuals, group or community (as integrated with an overall program) to develop communication
strategies to promote positive behaviors which are appropriate to their
settings and thereby solving the world's most pressing health problems.
This in turn provides a supportive environment which will enable people
to initiate, sustain and maintain positive and desirable behavior outcomes.[1]
SBCC is the strategic use of communication to promote positive health outcomes, based on proven theories and models of behavior change.
SBCC employs a systematic process beginning with formative research and
behavior analysis, followed by communication planning, implementation,
and monitoring and evaluation. Audiences are carefully segmented,
messages and materials are pre-tested, and mass media (which include
radio, television, billboards, print material, internet), interpersonal
channels (such as client-provider interaction, group presentations) and
community mobilisation are used to achieve defined behavioral
objectives.[2]
Providing
people with information and teaching them how they should behave does
not lead to desirable change in their response/behavior. However, when
there is a supportive environment with information and communication
(teaching) then there is a desirable change in the behavior of the
target group. Thus, SBCC is proved to be an instructional intervention
which has a close interface with education and communication. It is a
strategic and group oriented form of communication to perceive a desired
change in behavior of target group.[3]
However, it is not as easy as it sounds, as there is no
one-size-fits all strategy for any intervention. Interventions are
context specific. Therefore, there is a need for proper information
management and sharing. It is advised to document and report the
interventions that worked somewhere, for example, the kind of messages,
the medium and the audience.[4]
Steps
SBCC is the comprehensive process in which one passes through the stages:
Define SBCC strategy & monitoring and evaluation plan
Develop communication products
Pretest
Implement and monitor
Evaluate
Analyze feedback and revise
Enabling factors
Behavior
change is influenced by motivation from others (external influence) as
well as from within oneself (internal influence). Internal influence
plays a significant role in creating more enjoyment of a behavior
change, instilling a sense of ownership of the new behavior, which in
turn instills a sense of ownership of the changed behavior.[6]
When designing SBCC strategies, enabling factors that affect the
outcome must be considered. The following are some of the factors:[5]
Effective communication
Enabling environment, which include policies, human rights community values and norms
User-friendly, accessible services and commodities
Theories
SBCC
has several levels at which it can be implemented. Each level includes
several theories. Each level (and each theory) employs specific
communication channels.
The SBCC Summit 2018 in Bali, Indonesia, focusing on social and behavior change communication and featuring Entertainment-Education.Over
1,200 attendees came to the 2018 SBCC Summit, where
Entertainment-Education was a main topic among Social and Behavior
Chance Communications professionals.
Strategies
SBCC
is different from the ordinary instructional method of communication
and is target specific. A society consists of many sub-groups. The
strategy for SBCC will vary from group to group. The following points
are important while considering the SBCC strategy.[7]
Vulnerability/risk factor of the target group
The vulnerability/risk factor of the group which is to be addressed
The conflict and obstacles in the way to desired change in behavior
Type of message and communication media which can best be used to reach the target group
Type of resources available and assessment of existing knowledge of
the target group about the issue which is going to be dealt with
There can be several more points in this list. A successful SBCC
requires much research and meticulous planning about the knowledge
content of the subject and behavior/attitude pattern of the target
group.
Implications
SBCC
has proven effective in several health areas, such as increasing the
use of family planning methods, reducing the spread of malaria and other
infectious diseases, and improving newborn and maternal health.
SBCC is an effective tool for dealing with many community and
group related problems. BCC has been adapted as an effective strategy
for community mobilization, health and environmental education and various public outreach programs.
Enhanced knowledge about the behavior change process has facilitated the
design of communications programs to reduce the risk of HIV
transmission and AIDS. A wide variety of health promotion strategies use
communication as either an educational or norm-forming strategy. In
addition, specific strategies must be designed for high-risk groups such
as women, young people, injecting drug abusers, homosexuals and HIV
positive groups.
Role in HIV/AIDS
SBCC
consists of effective communication which is central to the success of
interventions to reduce the risk of HIV infection. It plays a role to:
Increase knowledge
Stimulate community dialogue
Promote essential attitude change
Advocate for policy changes
Create a demand for information and services
Reduce stigma and discrimination
Promote services for prevention and care
The visual map theory was published by the famous neuroscientist and pioneer Santiago Ramón y Cajal (1898). According to this theory, the function of the
optic chiasm is to repair the retinal field image on the visual cortex.
The pupil in the vertebrates’ eyes inverts the image on the retina, so
that the visual periphery projects to the medial side of the retina. By
the chiasmatic crossing, the visual periphery is again on the outside,
if one assumes that the retinal map is faithfully maintained throughout
the optic tract.
The theory has a number of weaknesses. For example, the visual tracts spiral their way from the thalamic LGN to the visual cortex. (See figure; this path is known as the optic radiation.)
As a result, the retinal map shows the visual periphery on the medial
side. However, the central objective of the theory was to obtain a
precise, faithful visual map with the medial field projecting to the
medial sides of the visual cortex.
Two twist hypotheses have been proposed independently: the axial twist by de Marc Lussanet and Jan Osse and the somatic twist by Marcel Kinsbourne. Both of them propose that the rostral
part of the head, including the forebrain, is in fact effectively
completely turned around. As a consequence, the left and right in the
brain are reversed, but also
Social and behavior change communication
From Wikipedia, the free encyclopedia
SBCC by health practitionerSBCC on the Development-Entertainment spectrum.
Social and behavior change communication (SBCC), often also only "BCC" or "Communication for Development (C4D)" is an interactive process of any intervention with individuals, group or community (as integrated with an overall program) to develop communication
strategies to promote positive behaviors which are appropriate to their
settings and thereby solving the world's most pressing health problems.
This in turn provides a supportive environment which will enable people
to initiate, sustain and maintain positive and desirable behavior outcomes.[1]
SBCC is the strategic use of communication to promote positive health outcomes, based on proven theories and models of behavior change.
SBCC employs a systematic process beginning with formative research and
behavior analysis, followed by communication planning, implementation,
and monitoring and evaluation. Audiences are carefully segmented,
messages and materials are pre-tested, and mass media (which include
radio, television, billboards, print material, internet), interpersonal
channels (such as client-provider interaction, group presentations) and
community mobilisation are used to achieve defined behavioral
objectives.
Providing
people with information and teaching them how they should behave does
not lead to desirable change in their response/behavior. However, when
there is a supportive environment with information and communication
(teaching) then there is a desirable change in the behavior of the
target group. Thus, SBCC is proved to be an instructional intervention
which has a close interface with education and communication. It is a
strategic and group oriented form of communication to perceive a desired
change in behavior of target group.
However, it is not as easy as it sounds, as there is no
one-size-fits all strategy for any intervention. Interventions are
context specific. Therefore, there is a need for proper information
management and sharing. It is advised to document and report the
interventions that worked somewhere, for example, the kind of messages,
the medium and the audience.
Steps
SBCC is the comprehensive process in which one passes through the stages:
Define SBCC strategy & monitoring and evaluation plan
Develop communication products
Pretest
Implement and monitor
Evaluate
Analyze feedback and revise
Enabling factors
Behavior
change is influenced by motivation from others (external influence) as
well as from within oneself (internal influence). Internal influence
plays a significant role in creating more enjoyment of a behavior
change, instilling a sense of ownership of the new behavior, which in
turn instills a sense of ownership of the changed behavior.
When designing SBCC strategies, enabling factors that affect the
outcome must be considered. The following are some of the factors:
Effective communication
Enabling environment, which include policies, human rights community values and norms
User-friendly, accessible services and commodities
Theories
SBCC
has several levels at which it can be implemented. Each level includes
several theories. Each level (and each theory) employs specific
communication channels.
The SBCC Summit 2018 in Bali, Indonesia, focusing on social and behavior change communication and featuring Entertainment-Education.Over
1,200 attendees came to the 2018 SBCC Summit, where
Entertainment-Education was a main topic among Social and Behavior
Chance Communications professionals.
Strategies
SBCC
is different from the ordinary instructional method of communication
and is target specific. A society consists of many sub-groups. The
strategy for SBCC will vary from group to group. The following points
are important while considering the SBCC strategy.
Vulnerability/risk factor of the target group
The vulnerability/risk factor of the group which is to be addressed
The conflict and obstacles in the way to desired change in behavior
Type of message and communication media which can best be used to reach the target group
Type of resources available and assessment of existing knowledge of
the target group about the issue which is going to be dealt with
There can be several more points in this list. A successful SBCC
requires much research and meticulous planning about the knowledge
content of the subject and behavior/attitude pattern of the target
group.[1]
SBCC
has proven effective in several health areas, such as increasing the
use of family planning methods, reducing the spread of malaria and other
infectious diseases, and improving newborn and maternal health.
SBCC is an effective tool for dealing with many community and
group related problems. BCC has been adapted as an effective strategy
for community mobilization, health and environmental education and various public outreach programs.
Enhanced knowledge about the behavior change process has facilitated the
design of communications programs to reduce the risk of HIV
transmission and AIDS. A wide variety of health promotion strategies use
communication as either an educational or norm-forming strategy. In
addition, specific strategies must be designed for high-risk groups such
as women, young people, injecting drug abusers, homosexuals and HIV
positive groups.
Role in HIV/AIDS
SBCC
consists of effective communication which is central to the success of
interventions to reduce the risk of HIV infection. It plays a role to:
Increase knowledge
Stimulate community dialogue
Promote essential attitude change
Advocate for policy changes
Create a demand for information and services
Reduce stigma and discrimination
Promote services for prevention and care
Whereas the somatic twist hypothesis focuses purely on the morphological
phenomenon of the inversions of the forebrain, the axial twist theory
also addresses the development and the evolution. Also, the axial twist
theory is at present the only theory that has produced predictions that have been tested independently.
Axial twist theory
lSchema
of the developmental twist, according to the axial twist hypothesis. A,
B: The early embryo turns onto its left side; B, C: Symmetry is
retained by a further left turn in the anterior head region and a
compensating right turn in the rest of the body. D, E: Growth of the
optic tract leading to the optic chiasm. Colors refer to early embryo:
Red=right side, blue=left side, black=dorsal, white=ventral.
The axial twist theory was designed to explain how the pattern of contralateral organization, decussations and chiasms develops, and why this pattern is so evolutionarily stable,
having no known exceptions throughout the 500 million years of
vertebrate evolution. According to the theory, the contralateral
organization develops as follows: The early embryo is turned onto its
left side, such that its left is turned to the yolk and its right is
turned away from the yolk. This asymmetric orientation is compensated by
asymmetric growth, to regain superficial bilateral symmetry. The
anterior head region turns to the left, as shown in the schema. The
forebrain is not a superficial structure, but it is so intimately
associated with superficial body structures that it turns along with the
anterior head. These structures will later form the eyes, nostrils and
mouth.
The body behind the head compensates the asymmetric body
orientation in the opposite direction, by turning to the right. (See
schema.) Due to these oppositely directed compensations of the anterior
head and the rest of the body, the animal becomes twisted.
The optic tract grows from the retina to the optic tectum.
Because dorsal and ventral are inverted in the anterior head region, the
tracts grow at first toward the ventral side, to meet in the midline to
form a chiasma. Since the optic tectum lies on the dorsal midbrain,
each tract then continues dorsally to the contralateral optic tectum.
The heart and bowels are internal organs with no strong
integration in external body structures, so there is no evolutionary
pressure to make them turn in a similar way. Rather, these organs retain
their original asymmetric orientation in the body.
The axial twist hypothesis predicts that small asymmetries of the
face and brain—as well as those found in the opposite direction in the
trunk—remain into adulthood, and this has been confirmed scientifically.
Comparing inversion, somatic twist and axial twist
According to the dorsoventral inversion hypothesis, an ancestral deuterostome turned on its back. As a result, vertebrates have a dorsal nervous system, whereas protostomes
have a ventral one. According to the somatic twist hypothesis, not the
entire animal turned on its back but just the somatic part—i.e.,
everything behind the eyes, mouth and nostrils, including the forebrain.
The somatic twist hypothesis was proposed as an improvement to
the inversion hypothesis, and thus has a much wider explanatory power
than its predecessor, but is also more complicated. It not only explains
the inversion of the body but additionally the contralateral forebrain.
It does not explain, however, how the twist might develop in the
vertebrate embryo, nor does it address the possible evolution.
The axial twist theory was defined independently of the
other two. In addition to providing rationale for the inverted body and
the contralateral forebrain, it explains why the heart and bowels are
asymmetric. Moreover, it is the only one of the three theories that is
supported by evidence from embryological growth, and it is the only
theory that has been tested independently.
Evolution
A remarkable property of the contralateral organization is that it is present in every vertebrate. Even the most distant clades—agnathans—possess an optic chiasm, and even the skull impressions of early vertebrates from the Ordovician show the presence of an optic chiasm: this idea was worked out by Kinsbourne.
There is molecular evidence for the inversion hypothesis in almost all groups of deuterostomes.
It is not known, however, what exactly was the selective pressure that
caused the inversion. Twisting and asymmetric development are well known
from other deuterostomes—such as Hemichordata, Echinodermata, Cephalochordata and Tunicata. Turning toward the side or upside-down also occurs frequently in these clades (e.g. sea stars which turn their mouth downwards after the larva has briefly settled with the mouth turned up, or the adult lancelet which buries obliquely with its mouth turned up, or many fish which tend to turn around when feeding from the water surface).
Developmental malformations
In holoprosencephaly,
the hemispheres of the cerebrum or part of it are not aligned on the
left and right side but only on the frontal and occipital sides of the
skull, and the head usually remains very small. According to the axial
twist hypothesis, this represents an extreme case of Yakovlevian torque, and
may occur when the cerebrum does not turn during early embryology.
Cephalopagus or janiceps twins are conjoined twins
who are born with two faces, one on either side of the head. These
twins have two brains and two spinal cords, but these are located on the
left and the right side of the body.
According to the axial twist hypothesis, the two nervous systems could
not turn due to the complex configuration of the body and therefore
remained on either side.
The
human brain is divided into two hemispheres–left and right. Scientists
continue to explore how some cognitive functions tend to be dominated by
one side or the other; that is, how they are lateralized.
Right cerebral hemisphere
Left cerebral hemisphere
The lateralization of brain function (or hemispheric dominance latralisation) is the tendency for some neural functions or cognitive processes to be specialized to one side of the brain or the other. The median longitudinal fissure separates the human brain into two distinct cerebral hemispheres, connected by the corpus callosum.
Although the macrostructure of the two hemispheres appears to be almost
identical, different composition of neuronal networks allows for
specialized function that is different in each hemisphere.
Lateralization of brain structures is based on general trends
expressed in healthy patients; however, there are numerous
counterexamples to each generalization. Each human's brain develops
differently, leading to unique lateralization in individuals. This is
different from specialization, as lateralization refers only to the
function of one structure divided between two hemispheres.
Specialization is much easier to observe as a trend, since it has a
stronger anthropological history.
The best example of an established lateralization is that of Broca's and Wernicke's areas, where both are often found exclusively on the left hemisphere. Function lateralization, such as semantics, intonation, accentuation, and prosody, has since been called into question and largely been found to have a neuronal basis in both hemispheres. Another example is that each hemisphere in the brain tends to represent one side of the body. In the cerebellum, this is the same body side, but in the forebrain this is predominantly the contralateral side.
Lateralized functions
Language
Language
functions such as grammar, vocabulary and literal meaning are typically
lateralized to the left hemisphere, especially in right-handed
individuals.
While language production is left-lateralized in up to 90% of
right-handers, it is more bilateral, or even right-lateralized, in
approximately 50% of left-handers.
This photo shows the left and right specialties of the brain.
Broca's area and Wernicke's area, associated with the production of speech and comprehension of speech, respectively, are located in the left cerebral hemisphere for about 95% of right-handers but about 70% of left-handers. Social interactions, demonstrating fierce emotions, and mathematical information are all provided by the right hemisphere.
Sensory processing
The
processing of basic sensory information is lateralized by being divided
into left and right sides of the body or the space around the body.
In vision, about half the neurons of the optic nerve from each eye cross to project to the opposite hemisphere, and about half do not cross to project to the hemisphere on the same side. This means that the left side of the visual field is processed largely by the visual cortex of the right hemisphere and vice versa for the right side of the visual field.
Because of this functional division of the left and right sides
of the body and of the space that surrounds it, the processing of
information in the sensory cortices is essentially identical. That is,
the processing of visual and auditory stimuli, spatial manipulation, facial perception, and artistic ability are represented bilaterally. Numerical estimation, comparison and online calculation depend on bilateral parietal regions
while exact calculation and fact retrieval are associated with left
parietal regions, perhaps due to their ties to linguistic processing.
Value systems
Rather
than just being a series of places where different brain modules occur,
there are running similarities in the kind of function seen in each
side, for instance how right-side impairment of drawing ability making
patients draw the parts of the subject matter with wholly incoherent
relationships, or where the kind of left-side damage seen in language
impairment not damaging the patient's ability to catch the significance
of intonation in speech. This has led British psychiatrist Iain McGilchrist to view the two hemispheres as having different value systems,
where the left hemisphere tends to reduce complex matters such as
ethics to rules and measures, and the right hemisphere is disposed to
the holistic and metaphorical.
Clinical significance
Depression is linked with a hyperactive right hemisphere, with evidence of selective involvement in "processing negative emotions,
pessimistic thoughts and unconstructive thinking styles", as well as
vigilance, arousal and self-reflection, and a relatively hypoactive left
hemisphere, "specifically involved in processing pleasurable
experiences" and "relatively more involved in decision-making
processes".
Additionally, "left hemisphere lesions result in an omissive response
bias or error pattern whereas right hemisphere lesions result in a
commissive response bias or error pattern." The delusional misidentification syndromes, reduplicative paramnesia and Capgras delusion are also often the result of right hemisphere lesions.
Lateral view of the Brain
Hemisphere damage
Damage
to either the right or left hemisphere, and its resulting deficits
provide insight into the function of the damaged area. There is truth to
the idea that some brain functions reside more on one side of the brain
than the other. We know this in part from what is lost when a stroke
affects a particular part of the brain. Left hemisphere damage has many
effects on language production and perception. Damage or lesions to the
right hemisphere can result in a lack of emotional prosody or intonation when speaking.
The left hemisphere is often involved with dealing of detail oriented
and perception while the right hemisphere is involved with mostly
overview and an overall concept of things.
Right hemisphere damage also has grave effects on understanding
discourse. People with damage to the right hemisphere have a reduced
ability to generate inferences, comprehend and produce main concepts,
and a reduced ability to manage alternative meanings. Furthermore,
people with right hemisphere damage often exhibit discourse that is
abrupt and perfunctory or verbose and excessive. They can also have
pragmatic deficits in situations of turn taking, topic maintenance and
shared knowledge.
Although both sides of the hemisphere has different responsibilities
and tasks, they both complete each other and create a bigger picture.
Lateral brain damage can also affect visual perceptual spatial
resolution. People with left hemisphere damage may have impaired
perception of high resolution, or detailed, aspects of an image. People
with right hemisphere damage may have impaired perception of low
resolution, or big picture, aspects of an image.
Plasticity
If
a specific region of the brain, or even an entire hemisphere, is
injured or destroyed, its functions can sometimes be assumed by a
neighboring region in the same hemisphere or the corresponding region in
the other hemisphere, depending upon the area damaged and the patient's
age.
When injury interferes with pathways from one area to another,
alternative (indirect) connections may develop to communicate
information with detached areas, despite the inefficiencies.
Broca's aphasia
Broca's aphasia is a specific type of expressive aphasia and is so named due to the aphasia that results from damage or lesions to the Broca's area
of the brain, that exists most commonly in the left inferior frontal
hemisphere. Thus, the aphasia that develops from the lack of functioning
of the Broca's area is an expressive and non-fluent aphasia. It is
called 'non-fluent' due to the issues that arise because Broca's area is
critical for language pronunciation and production. The area controls
some motor aspects of speech production and articulation of thoughts to
words and as such lesions to the area result in specific non-fluent
aphasia.
Wernicke's aphasia
Wernicke's aphasia is the result of damage to the area of the brain that is commonly in the left hemisphere above the Sylvian fissure. Damage to this area causes primarily a deficit in language comprehension. While the ability to speak fluently with normal melodic intonation is spared, the language produced by a person with Wernicke's aphasia is riddled with semantic
errors and may sound nonsensical to the listener. Wernicke's aphasia is
characterized by phonemic paraphasias, neologism or jargon. Another
characteristic of a person with Wernicke's aphasia is that they are
unconcerned by the mistakes that they are making.
Society and culture
Possible misapplication
Oversimplification of hemisphericity
The concept of "right-brained" or "left-brained" individuals is
considered a widespread myth which oversimplifies the true nature of the
brain's cerebral hemispheres (for a recent counter position, though,
see below). Proof leading to the "mythbuster" of the left-/right-brained
concept is increasing as more and more studies are brought to light.
Harvard Health Publishing includes a study from the University of Utah
in 2013, that exhibited brain scans revealing similarity on both sides
of the brain, personality and environmental factors aside.
Although certain functions show a degree of lateralization in the
brain—with language predominantly processed in the left hemisphere, and
spatial and nonverbal reasoning in the right—these functions are not
exclusively tied to one hemisphere.
Terence Hines
states that the research on brain lateralization is valid as a research
program, though commercial promoters have applied it to promote
subjects and products far outside the implications of the research. For example, the implications of the research have no bearing on psychological interventions such as eye movement desensitization and reprocessing (EMDR) and neurolinguistic programming, brain-training equipment, or management training.
Counter position
The debate as to being “right-brained” or “left-brained” has recently been reopened anew.
This re-opening is based on relatively recent neuroscience which has
refined the underlying primary functions of the two sides of the
neocortex. In particular, Elkhonon Goldberg's
“novelty-routinization” theory posits that the neocortex's right and
left hemispheres primarily process cognitively novel and cognitively
routine tasks, respectively.
(Thus, this theory fits with [novel] aspects of visual-spatial
processing predominantly occurring in the right hemisphere, as they tend
to be relatively novel; similarly, [familiar] aspects of language tend
to being predominantly processed in the left hemisphere, as they indeed
tend to be cognitively routine to us. New/novel aspects of language,
though, will fittingly be processed in the right-brain, just as familiar aspects of visual-spatial processing will be processed in the left-brain. [This explains why these functions are not exclusively tied to one hemisphere.])
As such, right-brained people favor the cognitively novel
tasks/information whereas left-brained people favor the cognitively
routine tasks/information. Or, in other words, right-brained people tend
to prefer new and novel experiences whereas left-brained people favor
familiar experiences. (Thus, this theory is the deeper understanding of
many of pop psychology's “oversimplifications” of lateralization. For
example, it explains why the right hemisphere has been considered
creative, as creativity tends to involve new and novel
information/tasks, whereas the left hemisphere has been considered
analytical, as analysis tends to be the re-processing of already
familiar information.)
This is not to say, though, that the tendencies of the left
hemisphere cannot be performed well by a right-brained person and vice
versa. For instance, right-brained people can exhibit strong analytical
skills and attention to detail (generally cognitively routine,
left-brained tasks), sometimes even surpassing their left-brained
counterparts, but their overall tendency is more so to instead be
synthesizing and to attend to the big picture (generally cognitively
new, right-hemisphere-tending tasks). (Such nuances are one reason this
thinking has been labeled a myth.)
Based on Goldberg's theory, the following table provides newly identified preferences of left- and right-brained people.
Preference Category
Left-brained People
Right-brained People
Experience Type
Familiar and Existing
New and Novel
Learning/Action Pattern
Learn, then Do
Do, then Learn
Improve or Create?
Improve
Create
Review or Discover?
Review
Discover
Depth or Breadth?
Depth
Breadth
Analyze or Action?
Analyze
Action
It is vital, though, to remember that these are only tendencies. At
times we may contradict our tendency to be left- or right-brained, but
often we can come to identify the underlying reason.
Furthermore, although less likely, some of us may be more bilobal, but
in general it seems most of demonstrate tendencies related to one side
or the other—in other words, most of us prefer either new and novel
experiences most of the time or we prefer familiar and known experiences
most of the time.
This is not to say, though, that we do not use the whole brain.
Life and personal growth require the use and development of both the
right and left hemispheres, as it requires the processing of novel,
unfamiliar situations as well as familiar, routine ones. Without this
ability, we would struggle to survive and thrive. Interestingly, as we
get older, we tend to become more set in our ways, which fits with many
older adults and seniors having struggles to stay up on technology and
other new and novel experiences.
The
oversimplification of lateralization in pop psychology. This belief was
widely held even in the scientific community for some years.
Some popularizations oversimplify the science about lateralization,
by presenting the functional differences between hemispheres as being
more absolute than is actually the case.Interestingly, research has shown quite opposite function of brain
lateralisation, i.e. left hemisphere creatively and chaotically links
between concepts and right hemisphere tends to adhere to specific date
and time, although generally adhering to the pattern of left-brain as
linguistic interpretation and right brain as spatio-temporal.
In the 19th century and to a lesser extent the 20th, it was thought
that each side of the brain was associated with a specific gender: the
left corresponding with masculinity and the right with femininity and
each half could function independently.
The right side of the brain was seen as the inferior and thought to be
prominent in women, savages, children, criminals, and the insane. A
prime example of this in fictional literature can be seen in Robert Louis Stevenson's Strange Case of Dr. Jekyll and Mr. Hyde.
History
Broca
One of the first indications of brain function lateralization resulted from the research of French physician Pierre Paul Broca, in 1861. His research involved the male patient nicknamed "Tan", who had a speech deficit (aphasia); "tan" was one of the few words he could articulate, hence his nickname. In Tan's autopsy, Broca determined he had a syphilitic lesion in the left cerebral hemisphere. This left frontal lobe brain area (Broca's area)
is an important speech production region. The motor aspects of speech
production deficits caused by damage to Broca's area are known as expressive aphasia. In clinical assessment of this type of aphasia, patients have difficulty producing speech.
Wernicke
German physician Karl Wernicke
continued in the vein of Broca's research by studying language deficits
unlike expressive aphasia. Wernicke noted that not every deficit was in
speech production; some were linguistic. He found that damage to the
left posterior, superior temporalgyrus (Wernicke's area) caused language comprehension deficits rather than speech production deficits, a syndrome known as receptive aphasia.
Imaging
These
seminal works on hemispheric specialization were done on patients or
postmortem brains, raising questions about the potential impact of
pathology on the research findings. New methods permit the in vivo comparison of the hemispheres in healthy subjects. Particularly, magnetic resonance imaging (MRI) and positron emission tomography (PET) are important because of their high spatial resolution and ability to image subcortical brain structures.
Movement and sensation
In the 1940s, neurosurgeon Wilder Penfield and his neurologist colleague Herbert Jasper developed a technique of brain mapping to help reduce side effects caused by surgery to treat epilepsy. They stimulated motor and somatosensory cortices
of the brain with small electrical currents to activate discrete brain
regions. They found that stimulation of one hemisphere's motor cortex
produces muscle contraction on the opposite side of the body. Furthermore, the functional map of the motor and sensory cortices is fairly consistent from person to person; Penfield and Jasper's famous pictures of the motor and sensory homunculi were the result.
Research by Michael Gazzaniga and Roger Wolcott Sperry in the 1960s on split-brain patients led to an even greater understanding of functional laterality. Split-brain patients are patients who have undergone corpus callosotomy (usually as a treatment for severe epilepsy), a severing of a large part of the corpus callosum.
The corpus callosum connects the two hemispheres of the brain and
allows them to communicate. When these connections are cut, the two
halves of the brain have a reduced capacity to communicate with each
other. This led to many interesting behavioral
phenomena that allowed Gazzaniga and Sperry to study the contributions
of each hemisphere to various cognitive and perceptual processes. One of
their main findings was that the right hemisphere was capable of
rudimentary language processing, but often has no lexical or grammatical
abilities. Eran Zaidel also studied such patients and found some evidence for the right hemisphere having at least some syntactic ability.
Language is primarily localized in the left hemisphere. While the
left hemisphere has proven to be more optimized for language, the right
hemisphere has the capacity with emotions, such as sarcasm, that can
express prosody in sentences when speaking. According to Sheppard and
Hillis, "The right hemisphere is critical for perceiving sarcasm (Davis
et al., 2016), integrating context required for understanding metaphor,
inference, and humour, as well as recognizing and expressing affective
or emotional prosody—changes in pitch, rhythm, rate, and loudness that
convey emotions".
One of the experiments carried out by Gazzaniga involved a split-brain
male patient sitting in front of a computer screen while having words
and images presented on either side of the screen, and the visual
stimuli would go to either the right or left visual field, and thus the
left or right brain, respectively. It was observed that if the patient
was presented with an image to his left visual field (right brain), he
would report not seeing anything. If he was able to feel around for
certain objects, he could accurately pick out the correct object,
despite not having the ability to verbalize what he saw.
Additional images
Ventricles of brain and basal ganglia. Superior view. Horizontal section. Deep dissection
Ventricles of brain and basal ganglia. Superior view. Horizontal section. Deep dissection
In marketing, a product is an object, or system, or service made available for consumer use as of the consumer demand; it is anything that can be offered to a market to satisfy the desire or need of a customer. In retailing, products are often referred to as merchandise, and in manufacturing, products are bought as raw materials and then sold as finished goods. A service is also regarded as a type of product.
In project management, products are the formal definition of the project deliverables that make up or contribute to delivering the objectives of the project.
A related concept is that of a sub-product, a secondary but useful result of a production process.
Dangerous products, particularly physical ones, that cause injuries to consumers or bystanders may be subject to product liability.
Product classification
A product can be classified as tangible or intangible.
A tangible product is an actual physical object that can be perceived
by touch such as a building, vehicle, gadget, or clothing. An intangible
product is a product that can only be perceived indirectly such as an
insurance policy. These services can be broadly classified under intangible products, which can be durable or nondurable.
By use
In its online product catalog, retailer Sears, Roebuck and Company divides its products into "departments", then presents products to potential shoppers according to (1) function or (2) brand.
Each product has a Sears item number and a manufacturer's model number.
Sears uses the departments and product groupings with the intention of
helping customers browse products by function or brand within a
traditional department-store structure.
By association
A
product line is "a group of products that are closely related, either
because they function in a similar manner, are sold to the same customer
groups, are marketed through the same types of outlets, or fall within
given price ranges."
Many businesses offer a range of product lines which may be unique to a
single organisation or may be common across the business's industry. In
2002 the US Census compiled revenue figures for the finance and
insurance industry by various product lines such as "accident, health
and medical insurance premiums" and "income from secured consumer
loans". Within the insurance industry, product lines are indicated by the type of risk coverage, such as auto insurance, commercial insurance and life insurance.
National and international product classifications
Various
classification systems for products have been developed for economic
statistical purposes. The NAFTA signatories are working on a system that
classifies products called NAPCS as a companion to the North American Industry Classification System (NAICS). The European Union uses a "Classification of Products by Activity" among other product classifications. The United Nations also classifies products for international economic activity reporting.
The Aspinwall Classification System classifies and rates products based on five variables:
Replacement rate (How frequently is the product repurchased?)
Gross margin (How much profit is obtained from each product?)
Buyer goal adjustment (How flexible are the buyers' purchasing habits with regard to this product?)
Duration of product satisfaction (How long will the product produce benefits for the user?)
Duration of buyer search behavior (How long will consumers shop for the product?)
The National Institute of Governmental Purchasing (NIGP) developed a commodity and services classification system for use by state and local governments, the NIGP Code.
The NIGP Code is used by 33 states within the United States as well as
thousands of cities, counties and political subdivisions. The NIGP
Code is a hierarchical schema consisting of a 3 digit class, 5 digit
class-item, 7 digit class-item-group, and an 11 digit
class-item-group-detail.
Applications of the NIGP Code include vendor registration, inventory
item identification, contract item management, spend analysis, and
strategic sourcing.
Product model
A manufacturer usually provides an identifier for each particular design of product they make, known as a model, model variant, or model number (often abbreviated as MN, M/N or model no., and sometimes as M- or Mk). For example, Dyson Ltd,
a manufacturer of appliances (mainly vacuum cleaners), requires
customers to identify their model in the support section of the website. Brand and model can be used together to identify products in the market. The model number is not necessarily the same as the manufacturer part number (MPN).
Because of the huge amount of similar products in the automotive industry,
there is a special kind of defining a car with options (marks,
attributes) that represent the characteristics features of the vehicle. A
model of a car is defined by some basic options like body, engine,
gearbox, and axles. The variants of a model (often called the trim levels)
are built by some additional options like color, seats, wheels,
mirrors, other trims, entertainment and assistant systems, etc. Options,
that exclude each other (pairwise) build an option family. That means
that you can choose only one option for each family and you have to
choose exactly one option.
In addition, a specific unit of a product is often (and in some contexts must be) identified by a serial number,
which is necessary to distinguish products with the same product
definition. In the case of automotive products, it is called the vehicle identification number (VIN), an internationally standardised format.
Many of these types of product information are regulated to some
degree, such as to some degree prohibiting false or misleading product
information or requiring sellers or manufacturers to specify various
information such as ingredients of food-, pharmaceutical- and
hygiene-products. There also is standardization. Marketing to entice the shopper is often prioritized over accurate, high-quality or extensive and relevant information.
Product information is often a key element in the buyer decision process. Relevant factors include trust in the accuracy of the information and social normative pressure. Easily accessible and up-to-date medicinal product information can contribute to the health literacy.
Online shopping is usually more informationally rich than shopping at
physical stores traveled to and usually has higher comparability and
customizability.
Production information-related developments can be useful for enabling, facilitating, or shifting towards sustainable consumption and support more sustainable products. Environmental life-cycle assessment (LCA) has been widely used for to assess environmental impacts across the life cycle of products. There are LCA datasets that assess all products in some supermarkets in a standardized way.Consumers may seek reliable information to evaluate relevant characteristics of products such as durability and reliability.
Development of 'transparency by design' scenarios have been suggested
to "complement the physical product with layers of digital information",
improving transparency and traceability (T&T). The app CodeCheck gives some smartphone users some capability to scan products for assessed ingredients.
Many labels are considered to be flawed and few have the time to "study
the true environmental impact of every purchase". Full product
transparency is a concept of making the full life-cycle impacts public. An important element that is required for various product information is supply chain transparency, which relates to human rights and supply chain sustainability.
Produce traceability
Produce traceability makes it possible to track produce from its point of origin to a retail location where it is purchased by consumers.
Produce traceability
is an important link in protecting public health since it allows health
agencies to more quickly and accurately identify the source of contaminated fruit or vegetables believed to be the cause of an outbreak of foodborne illness, remove them from the marketplace, and communicate to the supply chain.
Product passports
In the EU, under the renewed Sustainable Product Policy Initiative, the inclusion of a Digital Product Passport has been proposed. A material passport
is a document consisting of all the materials that are included in a
product or construction. It consists of a set of data describing defined
characteristics of materials in products, useful for recovery, recycling, re-use and various evaluations. They may contribute to a more circular economy.
Product information management
Product information management (PIM) is the process of managing all the information required to market and sell products through distribution channels. This product data is created by an internal organization to support a multichannel marketing strategy. A central hub of product data can be used to distribute information to sales channels such as e-commerce websites, print catalogues, marketplaces such as Amazon and Google Shopping, social media platforms like Instagram and electronic data feeds to trading partners. Moreover, the significant role that PIM plays is reducing the abandonment rate by giving better product information.
wide array of products and/or complex product data set
frequently changing product characteristics
increasing number of sales channels
non-uniform information technology infrastructure (plethora of data sources and formats)
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