Download Physiological bases of mental and physical work

Physiological bases
of mental and
physical work
The first signaling system
 The analysis and synthesis of the direct
stimuli from surroundings first signal system
performs. This includes impressions,
sensations.
 This functional mechanism is common in
human and animals. In the course of his
social development and labor activity second
signal system, which based on using verbal
signals, develop. This system includes
perception of words, reading and speech.
The second signaling system
 The development of the second signaling system was
incredibly broadened and changed by quality of higher
nervous activity of cerebral hemispheres. Words are
signals of other signals. Man uses verbal signals for
everything he perceives through the receptors. Words
are abstraction of reality and allow generalization,
processing of surrounding primary information. This
gives the first general human empiricism and finally
science, the instrument of man's higher orientation in
the environment and its own self.
 So, second signaling system is socially determined.
Outside the society, without association with other
people second signaling system is not developed.
 Wernicke's area is a
part of auditory
associative cortex,
that makes possible
to the person to
interpret the
meanings of words.
This Wernicke's area
is located in dominant
hemisphere, which is
usually the left.
 The process of
speech includes two
principle stages of
mentation: formation
of thoughts to be
expressed and motor
control of vocalization.
Motor control of speech function
 The skilled motor patterns for control of the larynx, lips, mouth,
respiratory system and other accessory muscles of speech
are all initiated from this area. Articulation means movements
of mouth, tongue, larynx, vocal cords, and so forth that are
responsible for the intonations, timing, and rapid changes in
intensities of the sequential sounds. The facial and laryngeal
regions of the motor cortex activate these muscles, and the
cerebellum, basal ganglia, and sensory cortex all help control
the sequences and intensities of muscle contractions.
 Transmitters such as dopamine, noradrenaline, serotonin and
certain neuropeptides transmit their signals by what is referred
to as slow synaptic transmission. The resulting change in the
function of the nerve cell may last from seconds to hours. This
type of signal transmission is responsible for a number of
basal functions in the nervous system and is of importance for
e.g. alertness and mood. Slow synaptic transmission can also
control fast synaptic transmission, which in turn enables e.g.
speech, movements and sensory perception.
Nerve substrate of speech
 There are two aspects of communication: sensory,
involving reading, hearing of speech, and second,
the motor aspect, involving vocalization and its
control.
 The formation of thoughts is the function of
associative areas in the brain. Wernicke's area in the
posterior part of the superior temporal gyrus is most
important for this ability. Broca's speech area lies in
prefrontal and premotor facial region in the left
hemisphere.
 The skilled motor patterns for control of the larynx,
lips, mouth, respiratory system and other accessory
muscles of speech are all initiated from this area.
Development of signaling
systems in children
 The ability of a full-term baby to develop temporary
connections of the first signaling system arises in a few
days after the birth. In the first six months of life speech
sounds mean little to a child. They are simply stimuli to
the auditory analyzer like any other sounds.
 The first signs of development of the second signaling
system appear during the second half of the first year
of life. If a person or an object is named and shown to
a child many times, reaction to this name develops.
 Later after leaning a few words, a child begins to name
objects itself. Finally, at a later time he uses a stock of
words to communicate with other people.
Language development
 The process by which children acquire their first
language in early childhood.
 Human infants are acutely attuned to the human voice,
and prefer it above all other sounds. In fact, they prefer
the higher pitch ranges characteristic of female voices.
They are also attentive to the human face, particularly
the eyes, which they stare at even more if the face is
talking.
 These preferences are present at birth, and some
research indicates that babies even listen to their
mother’s voice during the last few months of
pregnancy.
 Babies who were read to by their mothers while in the
womb showed the ability to pick out her voice from
among other female voices.
Functions of speech
 Main functions of speech are communicative, regulatory,
programming and gives general notion about surroundings.
Communicative function permits exchange of information between
people. Such a function is also present in animals, which use for
this aim vocalization of different intensity to warn about danger or
express positive and negative emotions. People use verbal signals
for everything he perceives through the receptors. Words are
abstraction of reality and allow generalization, processing of
surrounding primary information.
 Verbal instructions may direct human activity, give suggestion
about proper mode of behavior. This is programming function of
speech. Programming function of speech involves emotional
component also, which may influence to emotional status of a
person.
 As limbic system, which controls emotions, has direct connection
with autonomic nervous system, so speech through emotions may
influence to functions of visceral organs. Physician may use this
effect for psychotherapy. It is necessary remember about
jatrogenic disorders also.
Attention as psychical
function
 Attention is selectiveness of psychical
processes or any kind of mental activity, which
helps in getting and processing the information.
There are sensory, motor, intellectual and
emotional forms of attention, depending to kind
of activity of a person.
 There are voluntary and involuntary levels of
attention. Involuntary attention is present from
the birth of man. Voluntary attention develops
in life course, due to mental activity, formation
of speech function and studying languages.
Physiological mechanisms
of attention
 Involuntary attention is controlled by lower
portion of brain stem and midbrain, where
centers of roof reflexes are locates. Voluntary
attention appears as a result of higher cortical
activity in visual, auditory, motor areas and so
on.
 Lesion of these cortical areas leads to such
disturbances in processing special sensory
information as ignore of stimuli of different
modality. Intellectual attention appears
because of function of prefrontal associative
cortical area. The limbic system of the brain is
responsible for emotional attention.
Thinking process as psychical function
 The prefrontal association area is essential to carrying out
thought processes in the mind. This presumably results from
some of the same capabilities of the prefrontal cortex that
allow it to plan motor activities.
 The prefrontal association area is frequently described as
important for elaboration of thoughts to store on a short-term
basis “working memories” that are used to analyze each new
thought while it is entering the braine. The somatic, visual,
and auditory association areas all meet one another in the
posterior part of the superior temporal lobe. This area is
especially highly developed in the dominant side of the brain
– the left side in almost all right-handed people.
 It plays the greatest single role of any part of cerebral cortex
in the higher comprehensive levels of brain function that we
call intelligence. This zone is also called general
interpretative area, the gnostic area, the knowing area,
tertiary association area. It is best known as Wernike’s area
in honor of the neurologist who first describes it.
Brain activity recorded with PET in
examenee, watching the rotating
letters
FORGETTING
 Ineffective initial encoding, usually occurs because of ineffective
attention in the acquisition phase
 DECAY: forgetting occurs because memory fades with time.
 INTERFERENCE: forgetting occurs because of competition from
other information
 Retroactive Interference: new information interferes with what
has already been learned
 Proactive Interference: old information interferes with what is
being learned
 RETRIEVAL FAILURE: sometimes we can not remember
something which at another time we can remember it; perhaps
this is because of the context cues or retrieval cues present at the
time
 motivated forgetting: we may tend to forget things that we do not
wish to remember (Freud) (Repressed Memories )
 BRAIN INJURY:
 ANTEROGRADE AMNESIA (injury prevents new memories
from occurring):
 RETROGRADE AMNESIA: (injury prevents old memories from
occurring)
Thinking an Reasoning
 Thinking includes a wide range of mental activities. It is the language
of our mind, and it can be presented in different ways or modes.
These include: Propositional Thought, Imaginal thought, and the
Motoric thought.
 (I) PROPOSITIONAL THINKING:
 1) Three important aspects of proposition thinking can be studied:
its Content, its Organization, and its way of Communication.
 2)Content : refers to how we form or build blocks of thought and how
we use them to classify objects.
 -This is done through the development of CONCEPT FORMATION.
 -A concept is a set of properties that we associate with classes of
objects. It is the basis of categorizing items to their shared properties,
e.g. classes of antibiotics, or antipsychotic. It also helps us to predict
information that is not accessible to us, e.g. a cat, a lion etc.
PROPOSITIONAL
THINKING
 3) Organization of thought refers to the ways and types of
reasoning we use. In reasoning our sequence of thoughts often
take the form of an argument, in which one proposition correspond
to a Conclusion, and the remaining correspond to the premises.
 There is two type of reasoning: Deductive, and inductive
reasoning.
 Deductive reasoning are the strongest types of logical
reasoning. It means that it is impossible for the conclusion of an
argument to be false if its premises are true. Here we go from the
general to the specific; we deduce a particular consequence
from set of general rules, we Infer the conclusion from the
premises.
 Inductive reasoning represents the reversed process of
reasoning; here we try to induce a general rule from particular
premises. Here it is improbable that the conclusion is false if the
premises are true.
Communicating our
Thoughts
Communicating our
Thoughts is achieved
through language.

Next level is that of WORDS
and parts of words that carries
meanings a MORPHEME.
 Languages are organized
as a hierarchy of structures.

Morphemes are words, suffix
or prefix that are added to
words.
 The highest level is
SENTENCE UNITS,
including phrases that can
be related to units of
proposition. The phrases of
a sentence are built of
words, or parts of words
that have meaning,

The lowest level contains
SPEECH SOUNDS.

A phoneme is a category of
speech sounds. Every
language has its own set of
phonemes and rules that
combining them into words.

4)
Understanding and
Expressing LANGUAGE
 A language also has syntactic rules for combining words
into phrases and phrases into sentences.
 Producing language is a process of translating
propositional thoughts into the phrases and morphemes
of the sentence, and then translating this into phonemes.
 PHRASES-------- MORPHEMES------- PHONEMES
 Understanding a sentence requires not only analyzing
phonemes, morphemes, and phrases, but also using the
context and understanding the intention of the speaker.
In understanding language the process is reversed. That
is, we use phonemes to construct morphemes, and then
phrases
 TYPES OF APHASIA
OTHER TYPES OF
THINKING
 IMAGINAL THOUGHTS:
 1) Not all types of our
thoughts are presented in
proposition. Some are
presented in visual images.
Such images contains the
kinds of details found in
visual perception
 2) Imagery can be like
perception because it is
mediated by the same part
of the brain. Thus, brain
damage that results in
certain perceptual
problems, e.g., visual
neglect, also results in
comparable problems in
imagery.
 THOUGHT INACTION:
PROBLEM SOL VING:
 1) Problem solving
involves decomposing a
goal into subgoals that are
easier to obtain.
 2) We use different
strategies to solve daily
problems That why experts
are superior to novice in
problem solving.
 The IDEAL problem solver
refer to effective strategy
and planning for problem
solving.
Aphasia
Aphasia means loss of speech .
There are several types of aphasia :
 1) Broca's Aphasia
 2) Wernik's Aphasia
 3) Anomic Aphasia
 4) Conducting Aphasia
 5) Global Aphasia
 6) Transcortical Sensory Aphasia
 7) Transcortical Motor Aphasia
Broca's Aphasia
 Broca's area is usually found in the Frontal
Lobe
 In 90% of the people , it is found in the Lt
hemisphere
 It is the most common type of Aphasia
 The patient understands what he hears but he
can NOT speak !
 He speaks very few words , very difficult
Broca's Aphasia
(NON-FLUENT Aphasia )
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The patient is minimizing the adverbs & adjectives
It is really difficult to produce the words in such patients
He is laboring to produce only few words !
The patient doesn't talk much , he is almost silent
He will omit a lot of syntaxes .. The grammar is
simplified
 The language is meaningful but it is hard to generate
the words
 The words are produced very slow & with a lot of effort
 If you ask him a question he will answer you , He will
follow your comments because he can understand
what you say
Wernik's Aphasia
(FLUENT Aphasia)

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Wernik's area is usually found in the Temporal Lobe
In 90% of the people , it is found in the Lt hemisphere
The patient speaks a lot but his sentences has NO meaning
If you listen to him , He speaks very fluent sentences , he speaks
all the time ..
His sound is normal , He uses correct grammar roles but if you
concentrate on what he is saying you would found meaningless
speech..
Ex : The door is too salty , The book is extremely fast !
The patients are very confident , very elated & euphoric , they
think that they are fine !
If you ask him to follow your comments , he will not be able to do it
because he can NOT understand what you say ( Lack of
comprehension)
Anomic Aphasia
(Angular Gyrus Lesion)
 Anomic person can Not supply the proper word or the
name of an object or any thing he talks about
 Anomic person can Not find the proper word or the
name of an object he talks about so he keeps on
describing that object without mentioning its name
 Ex : If you give him a picture of a computer for
example he would say :
 Yes I have this , I have it on my office , above my disc ,
I use it every day , it is like this & that …
 Yet , he can NOT say that this is a computer !!
 Anomic person is Alixic !
 Anomic person can understand & read !
Conduction Aphasia
(Arcuate Fasiculus Lesion)
 Damage of the connection fibers between the Werniks
area & Broca's area ..
 These patients will have problem in repetition .. They
can Not repeat after you although they understand
what you say ( bcz Werniks area is Normal ) ..
 They can follow your comments ..
 Thy have problem in conjugation of the words ..
 Ex : If you give him a picture of a chair for example he
would say :
 Tair … Flair … Sair …
 He can Not say the proper word or the name of the
object he sees ..