This document discusses consciousness, cognition, and memory. It begins with definitions of consciousness, noting that it allows perception of the environment and response. Consciousness requires arousal and awareness. It then discusses grades of consciousness from fully conscious to comatose. Examination of consciousness involves tools like the Glasgow Coma Scale. Consciousness requires integration of the cerebral hemispheres and reticular formation. The document also discusses cognition, including distributed functions like attention, memory, and higher cognitive functions, as well as localized functions including language, calculation, praxis, and visuospatial skills.

1. CONSCIOUSNESS, COGNITION & MEMORY
Dr.Mohamed Elshafei
DR.LINK147@YAHOO.COM

2. CONSCIOUSNESS
 Definitions
 Grades
 Examination
 Anatomy
 Assessment

3. • Consciousness : it`s the status that allow the
person to perceive and understand the
environment and respond to what`s perceived .
• It requires :
Arousal
Awareness
Definitions

4. Arousal :
• How will subject
able to interact with
the environment
• e.g whether they are
awake or sleeping
Awareness :
• the depth and content
of aroused state
Attention :
• depend on awareness
• it emplies concen-
tration and persist-
ance.

5. Fully consciouss
Confused Drowsy
Delirious
Stuperous
Comatosed
Grades

6. Coma
• (from the Greek κώμα [ko
̞ ma], meaning deep sleep).
• It is a state of unconsciousness lasting more than 6
hours, in which a person cannot be awakened, fails to
respond normally to painful stimuli, light or sound,
lacks a normal sleep-wake cycle and does not initiate
voluntary actions.
• This is not reliable and the better description is by
using Glasgow Coma Score (not as anumber but
better E4V5M6)

7. 1- Glasgow Coma Score (GCS)
2- Full Outline of Unesponsiveness (FOUR)
score
3- Richmond Agitation Sedation Scale (RASS)
Examination

8. 1- Glasgow Coma Score (GCS)

9. 2- Full Outline of Unesponsiveness
(FOUR) score

10. 3- Richmond Agitation Sedation Scale (RASS)

11. - Consciousness requires integration of 2 systems :
1- Cerebral hemispheres
2- Reticular formation of midbrain
- So, counsciouss level affected in :
1- Bilateral corical lesion causing brain displacement
and impair the function of RF
2- Damage of RF in Midbrain
RAS
Anatomy

12. -To differentiate between cortical and brainstem
causes of unconsciousness

DO : brainstem reflexes :
1- Pupillary response  midbrain
2- Corneal reflex  pontomedullary junction
3- Gag reflex  lower brainstem
4- Spontaneous respiratory movement  integrity of
medullary respiratory centers
Assessment

15. A: The ascending RF project to the thalamus, hypothalamus and basal forebrain
B : Orexin neuron project to the ascending RF and directly to the cortex

16. RAS

17. BEHAVIOR
The manner in which a person acts.
It includes :
• Mood:
- Depressed , euphoric, anxious, labile.
• Thought:
- Organization(muddled, mild delirium),
- Content (delusion, illusion, hallucinations)
• Degree of psychomotor activity:
- Hyperalert (restless),
- Hypoalert (motionless)
It`s apart of psychiatric exam.
Cognition is prefered in neurological exam.

18. Cognition
The process of knowing
1- Distributed :
• require extensive
anatomical network .
• impairment of them
need more work up for
localization
2- Localized :
• utilize more localized
brain area.
• impairment of them
may be of localizing
value

20. Cognitive Functions
Distributed Localized
Attention
Higher order
intellectual function
Memory
Dominant Non-dominant
Language
Calculation
Praxis
Spatially
directed
attention
Constructio-
nal abilities
Complex visuo-
perceptual skills

21. Distributed Cognitive Functions
Definition : it implies concentration and persistance.
Anatomy : Neocortex (esp. prefrontal), thalamus,
Brainstem ----> linked by RAS
Examination : Bedside tests
1- Orientation
2- Digit span
3- Months of year backward
4- Subtraction (serial sevens…)
1- Attention

24. Impaired attention : inability to focus and
concentrate on a topic with impersistance,
distractability, and often
disorientation e.g
acute confusional state
Causes : it`s caused by
any lesion affecting the distrubuted system or
metabolic disturbance affecting RAS

25. 1- Attention

26.  Acute confusion in elderly  consider underlying infection,
if not ; look for drug intake
 Acute confusion in young pt.  consider neurological cause
 Acute confusion state can present with either agitation and
tremeloussness or with lethergy
 Causes of Wernicke`s encephalopathy :
- Chronic alcoholism
- Repeated vomiting
- Poor nutritional intake
 Memory disturbance in acute confusional state is d.t
impaired attention ;
# STM is affected d.t inability of pt to register new stimuli
d.t distractability.
# LTM is not affected but the proplem is to access it in the
presence of impaired attention

27. Distributed Cognitive Functions
 It involves :-
- Conceptual thinking
- Adaptation and set shifting
- Planning and proplem solving
- Personality, motivation and social behaviour
 Anatomy : it`s presented mainly in frontal
lobe
2- Higher Cognitive Functions

28.  Examination : Bedside tests
1- Fluency
2- Abstraction (proverb meaning)
3- Motor sequening (alternating hand movement)
 Impairment of this function : in frontal lobe damage
lead to Frontal Behaviour.
 Frontal lobe syndrome : subdivided into
# Orbitofrontal damage : result in personality and
behavioural changes
# Dorsolateral damage : result in defect in excecutive
function

30. Distributed Cognitive Function
3- Memory

31. Localized Cognitive Functions
 Anatomy : dominant hemisphere
 Comprehension >> presented in dominant
temporal lobe( posterior third of yhe
superior temporal gyrus)
 Expression >> presented in Broca`s area(
posterior third of inferior frontal gyrus )
 Pathology : Aphasia
 Assessment : Fluency >> Repetition >>
Comprehension >> Naming >> Reading
>> Writing.
Dominant (1- Language)

32.  Definition : acquired disorder in formulation of language
 Types : See Table ..
 Testing :
Fluency >> Repetition
>> Comprehension >> Naming
>> Reading >> Writing.
 Causes :
1- Brain injury or stroke.
2- neurodegeneration
 Presentation :
1- difficulity using words and sentences (expressive)
2- difficulity to understand others (receptive)
3- difficulity with both (global)
Aphasia

35. Diagram to illustrate the anatomy of articulation

37. Syndrome Repetition Compreh-
ension
Fluency Naming Reading Writing Hemi-
paresis
Lesion
Localization
TCM + + - - ± - common Frontal
convexity
TCS + - + - - - infrequent Parietal
convexity
Anomic + + + - ± - infrequent Angular and
supramarginal
gyri
Broca`s - + - - ± - common Frontal
operculum
Wernicke`s - - + - - - infrequent Posterior
superior
temporal lobe
Conduction - + + ± ± - infrequent Angular and
supramarginal
gyri
(inferior
parietal lobule)
Global - - - - - - common Frontal,
Parietal, and
Temporal
operculum

39. Abnormalities
Encountered in Aphasic
Speech :
- Reduced fluency
- Reduced prosody
- Paraphasia
- Paragrammatism
- Agrammatism
- Recurrent utterance

40. Localized Cognitive Functions
 Anatomy : represented in
angular gyrus of dominant hemisphere
 Pathology :
• Inability to write or understand numbers.
• Usually associated with aphasia
** When occuring with inability to write , rt-lt disorientation
, and finger agnosia >>> Gerstmann`s syndrome
Dominant (2- calculation)

41. Localized Cognitive Functions
 Definition : it`s ability to perform and control
skilled or complex motor actions
 Pathology : Apraxia
 Anatomy :
1- Anterior (frontal) apraxia:
limb-kinetic type
2- Posterior (parietal) apraxia:
ideomotor or ideational types
Dominant (3- Praxis)

42.  Definition : Impaired motor activity not
explained by Weakness, Incoordination,
Abnormal tone, Bradykinesia, Movement disorder,
Dementia, Aphasia, or Poor cooperation
 Types : See Table ..
 Testing :
1- Pantomime >> show me how you would…..
2- Imitation >> watch how i….then you do it
3- Use of an actual object >> Here is a….show me how
you would use it
Apraxia

43. Apraxia may affect only selected movement
Gait apraxia
Orobuccal apraxia
Eyelid apraxia
•Dressing apraxia
•constructional apraxia
(now considered as visuospatial disorder not true apraxia )

45. Type Idea Individual
component
Whole
act
Lesion description
Ideomotor
+ + -
- Unilateral Lesion
of inferior parietal
lobule or premotor
area of frontal lobe
(Brodmann area
6&8) of dominant
hemisphere
- Use body parts
as objects
Ideational
(conceptual)
- + Incorrect - Extensive left
hemispheric lesion
or lesion of corpus
callosum
- Interfere with
daily activity
- Usually
associated with
aphasia
Limb-kinetic
(melokinetic)
+ - - - Unilateral lesion of
supplementary
motor area of
frontal lobe of
dominant
hemisphere
- Decomposition
of movement
- Diffecult to
differentiate from
pure motor
deficit

47. Localized Cognitive Functions
1- Spatially directed attention
2- Complex visuo-perceptual skills
3- Constructional abilities
 Anatomy : Association cortex of non-dominant
hemisphere and may be thalamus, basal ganglia, or cingulate gyrus.
 Pathology :
1- Neglect
2- Agnosia
3- Constructional apraxia
Non-dominant (Rt. hemisphere function)

48.  Definition : Failure to orient toward, respond
to, or report novel or meaningful stimuli.in
absence of sensory or motor deficit
 Anatomy : angular gyrus and
parahippocampal gyrus mostly in
right hemisphere
 Neglect may be :
- Obvious >> e.g patient not dressing one side
of the body
- Subtle >> need simple tests for examination
Neglect

49.  Clinically :
• Extrapersonal environment : e.g visual neglect
• Personal space : e.g personal neglect or
asomatognosia
• Neglect of contralateral hemispace : called
unilateral spatial neglect, hemiattention or
hemineglect.
• Double simultaneous stimulation : extinction
• Motor neglect : as hemiakinesia, hypokinesia
or motor impersistance.
• Alloesthesia or allokinesia may be afeature

50.  Testing :
1) Cancellation test e.g stars, letters
2) Figure copying e.g Rey-Osterreith figure
3) Line bisection, numbering a clock face
4) Drawing from memory e.g
drawing double headed daisy

52.  Definition : failure of recognition not explained by impaired
primary sensation or cognitive impairment.
 Anatomy : defect at the level of association cortex and
occasionally thalamic pathology.
 It may be :
- Apperceptive : defect of complex perceptual processes
- Associative : normal perception stripped of its meaning
Agnosia

53. Clinical types :
1- Tactile agnosia
(Astereognosis): Nothing
touched can be recognized
4- simultanagnosia : inability to
recognize the meaning of
whole scene or object even
though its individual
components are recognized
2- Visual agnosia : Nothing seen
can be recognized ::
- Visual object agnosia > inability
to recognize seen objects
- Prosopagnosia > inability to
recognize seen facies
5- Topographagnosia : difficulty
reading maps or find one`s
way about
3- Auditory agnosia : Nothing
heard can be recognized
6- Anosognosia : inability to
recognize a neurological deficit
e.g hemiplegia , memory , aphasia
….
** With the passage of time agnostic deficit merge into
anterograde amnesia ( failure to learn new informations).

55.  Ability to copy shape requires vision,
perception, and visuo-motor output
 So, it`s not true apraxia >> it`s visuospatial
disorder
 Anatomy : right parietal dysfunction
 Patient with right side lesion tend to produce
drawings with grossly altered spatial
arrangements while patient with left sided
lesions make oversimplified drawings.
Constructional apraxia

56. Evaluation Of cognition
** Cognitive History Taking
** Physical Examination
** Bedside Testing
Patient interview
Informant interview

57.  Ask about the presenting complaint (for insight) and how it affect
the daily activity
 Memory :
- Patient may use poor memory for many complaints like >>
X Forgetting his keys > lack of attention & concentration
X Forgetting names > Anomia (mostly in keep with semantic
memory impairment)
X Forgetting appointments > true episodic memory deficit
- So, Ask about Anterograde memory (ability to retain new
informations), Retrograde memory (ability to retrieve knowledge
about previous holidays), Semnatic memory (facts).
 Language :
- Ask about difficulty to express himself , difficulty in
reading,writing,dressing,constructing objects
Cognitive History taking
(Patient interview)

58.  The informant can provide further history that the patient cannot
 Ask about the presenting complaint and how it affects daily
activity
 Ask about Onset, Course and Duration
X Sudden Onset >> Vascular
X Acute Onset >> inflammatory
X Gradual progressive >> Neurodegenerative and tumors
 Past history of neurological or psychiatric disease, head trauma,
drug or alcohol intake
 Family history of similar condition, psychiatric disease
 Social history for patient occupation to estimate premorbid IQ
Cognitive History taking
(Informant interview)

59.  Detailed examination not routinely necessary
 Look for :
X Visual Field Deficit
X Eye Movement ; Both Saccades and Pursuit
X Specific Signs of frontal diseases e.g Pout reflex,
Grasp reflex, Pulmomental reflex (primitive reflexes)
X Involuntary Movements in HD
X Gait analysis in PD and NPH
Physical Examination

61. 1- Montreal Cognitive Assessment (MoCA)
(30 points) >> 10 minutes
2- Mini-Mental Score Examination (MMSE)
(30 points) >> 10 minutes
3- Adden Brooke`s Cognitive Exam. (ABCE)
(100 points) >> 20 minutes
BedSide Testing

75. MEMORY

76. MEMORY
Definition : it`s the process of recording,
retention and retrieval of knowledge
Types :
1- Declarative ( Explicit )
2- Non-declarative ( Implicit )
Definitions and Types

78. Definition : the everyday sense of memory and
is responsible for the learning and
remembrance of new events, facts, and
materials.
It is the form of memory people use to
recollect facts and events consciously and
intentionally and is therefore also referred to as
explicit memory.
Declarative memory

79. Types :
- Episodic >> remembrance of personal
experiences that took place at a particular
place and time e.g
( Remembering what happened in the previous
holiday)
- Semantic >> knowledge of generic
information, such as the meaning of a word e.g
( Knowing the capital of france )

80. Definition : the many forms of memory that are
not retrieved explicitly or intentionally but
reflexively or incidentally e.g remembering
how to swim or ride a bicycle
 These forms of memory guide current
behavior on the basis of past experiences
unrelated to any conscious awareness of those
experiences and therefore are referred to as
implicit memory.
Non-declarative memory

81. It includes :
1- skill learning : increased accuracy, speed, or skill
acquired for a given task during multiple training
sessions in the absence of conscious awareness so
referred as Procedural memory
2- conditioning : repeated pairing of an
unconditioned stimulus, such as a tone, with an
unconditioned response, such as salivation at the sight
of food, leads to a conditioned response (salivation)
when the tone is presented in the absence of the
evoking stimulus (food)
3- Repetition priming : facilitated processing of a
stimulus, such as a word or picture, due to prior
exposure to that stimulus.

82.  Short term memory (working or immediate memoty )
: it`s the system which retain informations for seconds .
Depend more on attention
 Long term memory : it`s system that retain
informations for minutes or more. It includes:
- Episodic memory
- Semantic memory
- Non-declarative memory
 Many physicians misunderstood STM as memory of days or
hours and LTM as memory for years.

84. MEMORY
1- Short term memory :
 Frontal lobe language area for verbal material
 non-dominant hemisphere for visual material
2- Episodic memory :
 Limbic system  Different parts have different roles
- Hippocampas  Laying down new memories and consolidation of
newly acquired ones.
- Thalamus  Laying down new memories and retrieval of old ones.
3- Semantic memory :
 Dominant temporal neocortex
4- Implicit memory :
 Rely on basal ganglia and cerebellum
Anatomy

86. SO,..
 Hippocampal pathology >>
 Anterograde amnesia (Difficulty encoding new ongoing
memories)
 Temporally limited retrograde amnesia (Impaired
consolidation of these very recently acquired before injury)
 Thalamic pathology >>
 Anterograde amnesia
 Temporally extensive retrograde amnesia
( pt has difficulty in recally events which occurs years or
decades before the onset of the pathology )

87. MEMORY
Disorders
Pure
(only memory)
Mixed
(+ other cogitive functions)
Episodic +
Semantic
Semantic Episodic
Neurodegenerative
disease e.g
ALZhiemer
** Damage of temporal neocortex e.g
- Temporal variant of FTD
- HSE - stroke
Transient Persistent
Delirium Dementia
Transient Persistent
-TGA - TEA
- Drugs
- Psychogenic
Hippocampal Diencephalic
- HSE
- Early ALZh.
- Hypoxia
- Korsakoff $
- Bilateral thalamic infarction
- 3rd Ventricle tumours