1. Dr Charulata Sankhla MD DNB
Higher Cortical Functions
Dr Charulata Sankhla MD DNB
P D Hinduja National Hospital
And Medical research Center

2. Higher cortical functions
Consciousness – awake, drowsy, stupor, coma
Orientation - time, person ,place
Cognition – attention, language, praxis, judgment, reasoning, abstract thinking, insight, visuospatial orientation, gnosis, calculation
Affect – mood, behavior
Higher cortical functions assessment involves levelof consciousness whether the pat is otiented in time person and place cognition attention language pr

3. Consciousness
Function of ARAS originating from brainstem, projecting to wide areas of bilateral cerebral networks.
Conscious – awake, aware
Drowsy – sleepy, arousable with verbal or mild physical stimulus but goes again into sleep once stimulus removed
Stupor – unconscious, responds to painful / vigorous mechanical stimulus
Coma – unconscious, not responding to painful stimulus.

4. Orientation To time, place and person
Any disturbance which is diffuse, due to reversible or progressive process
Examples – encephalopathy, drugs, severe dementia with severe memory impairment

5. Attention
Preservation of attention and language is necessary to proceed further with other higher function examinations.
Function of ARAS and bilateral frontal lobe
Tests :
1) digit span – forward - normal 5-7
backward – normal 3
2) spell/ days/ months – backward
3) serial 7s – subtract 7 consecutively 5 times from 100 – also checks calculation
4) vigilance – ask pt to tap when he hears a “A” when a series of letters presented to him

6. Language –Dominant Fronto temporal function
Perisylvian network in left dominant cortex
Aphasia is a acquired dysfunction of language
Spontaneous speech, comprehension, naming, repetition, reading, writing
Spontaneous speech :
Ask pt to describe his illness/ work
See fluency and grammar (motor speech area), prosody(non dominant motor speech area), articulation, paraphasia, neologism
normal fluency words/ min, sentence length >7 words
Reduced fluency in Brocas aphasia, transcortical motor, global aphasia, primary progressive aphasia

7. Comprehension Comprehension : ability to understand spoken language
Posterior superior temporal gyrus (broadman area 22)
1) pointing commands – ask to point at 4 objects or room or body part
2) yes/ no questions – 7 questions
3) complex command – if lion was killed by tiger , then which animal is dead?
Classically impaired in Wernicks aphasia

8. Repetition No if and or buts Sarashwati sishu bal vidyamanadir
Impaired in all aphasias except transcortical motor and transcortical sensory, anomic
Classically severely and only parameter impaired in conduction aphasia

9. Naming Colors Body parts Objects
Part of objects chain of wrist watch, shoe laces, buckle of belt
Very sensitive for any kind of language dysfunction.
anomia can be isolated as anomic aphasia or can be associated with other aphahsic syndroms

10. Reading
Alexia
Letters, numbers, words, paragraph – fluency, articulations and comprehension
Alexia without agraphia – posterior callosal / left deep occipital area involvement – classically in left PCA (P2) infarct, disconnecting visual association from language area
Alexia with agraphia – angular gyrus – gerstmann syndrome

11. Writing Agraphia Writing on narration/ spontaneous
Write letters/ words/ sentence / paragraph

12. Brocas aphasia
Spontaneous speech –telegraphic mute nonfluent produces less words
Naming impaired
Comprehension- intact with mild difficulty
Reading impaired often
Repetition impaired
Writing impaired dysgrammatical
Posterior part of inferior frontal gyrus -upper division of left MCA

13. Wernickes aphasia Spontaneous speech – fluent with paraphasia
Logorrhoea
Naming impaired bizzarre
Comprehension impaired
Repetition impaired
Reading reading aloud but comprehension impaired
Writing well formed with paraphasia
Posterior part of superior temporal gyrus, inferior parietal lobule

14. Conduction aphasia Spontaneous speech- fluent with some hesitancy
Naming - moderately impaired
Comprehension –intact
Repetition severely impaired
Reading cannot read aloud some reading comprehension
Writing deficits
Arcuate fasciculus

15. Differential of nonfluent speech/ condition mimicking nonfluent aphasia
Speech apraxia - : disorder of programmimg of articulation ,in a sequence of phonemes, especially consonants
Features
1) effortful
2) trial and error attempts – and self corrections
3) dysprosody
4) inconsistency in articulation errors- making one error at one time and different or no error next time with same word
5) difficulty in initiating utterance
Substrate : left insula, brocas area

16. Memory – A temporal lobe function
Digit span 7 numbers
Recent memory – recall
hippocampus (limbic system) parahippocampus
Medial temporal lobe
learning and recalling of events/ experiences
Give 4 words , ask after 5,10, 15 minutes. Recalling less than 3 words after 10 minutes is abnormal
Check visual memory in pts with motor aphasia – hide 5 objects and ask location and name of objects after 5 minutes – less than 4 is abnormal
Classically impaired early in Alzheimer's disease, also in bilateral MTS
Immediate memory – registration
Frontal lobe – attention – online holding of information
To be checked similarly as described in attention

17. Semantic memory – concepts / word meanings
Remote memory
personal information- name of grand parents, firstgrade school teacher
Stored in broad networks in bilateral cerebral hemisphere, gets affected in late stages of dementia
Semantic memory – concepts / word meanings
anterior temporal lobe
checked by categorical word fluency – name of animals /flowers in 1 minute – less than 13 is impaired
Classically impaired in Alzheimer's disease and semantic dementia

18. Implicit memory / procedural memory – basal ganglia, cerebellum
Driving from work to home
cycling

19. Parietal lobe Visuospatial (non dominant hemisphere)
---– geographic orientation (neglect)
---- construction (construction apraxia)
---- dressing (dressing apraxia)
Praxis (dominant hemisphere) – ability to perform learned skilled movement correctly
Calculation
Cortical sensations –tactile localisation, 2 point discrimination, sensory extinction, stereognosis, graphesthesia

20. neglect
1) simultaneous bilateral stimulation – visual, tactile, auditory – patient will neglect stimuli presented on left hemispace
Anosognosia – denial of deficit – left hemiplegia , in case of rt hemispheric stroke – different from true agnosia - essentially a form of neglect of left hemifield due to rt parietal involvement.
2) visual target cancellation
line bisection (ask pt to divide line in 2 )
letter cancellation ( tick all letter A from randomly written letters)

21. calculation construction Copy cubes/ triangles/ complex structure
Draw clock – it also tests for visuospatial orientation, planning, sequencing
calculation
Verbal simple, verbal complex, written complex
Rt left orientation

22. Apraxia
Acquired inability to correctly perform learned skilled movements in absence of motor, sensory or cerebellar dysfunction.
Action semantics and concepts – posterior parietal
movement formulas and gesture knowledge - Left inferior parietal lobule
Motor programs - Left supplementary motor area
Ask to pantomime use brush, comb, lock n key
Imitate the gesture – bye bye, come, good luck etc
Gesture knowledge - which gesture is it
Tool knowledge – which tool is it n what its used for
Use of real tool – give pt brush, comb, lock n key , hammer and use it
Causes – left parietal SOL, dementias – AD, corticobasal syndrome

23. Other traditional apraxias , not fitting into definition of true apraxia and have different localizing value
Dressing and construction apraxia – more related to visuospatial and self orientatation – rt parietal area
Oculomotor apraxia
Gait apraxia – bilateral frontal lobe
Speech apraxia
Oral/ buccolingual apraxia

24. Occipital
Hemianopia
Cortical blindness in case of B/L involvement – pupillary (always) and macular (mostly) sparing.
Extension of pathology into adjacent parietal lobes
color agnosia
anton syndrome – denial of blindness in a patient with cortical blindness
balint syndrome – optic ataxia – inability to trace an object with visual guidance.
optic apraxia – inability to voluntarily shift the gaze
+/_ asimultagnosia - inability to notify gross picture ,though able to pick up fine detail – misses forest for trees .
– ask patient to circle A , from random letters of varying size, patient might encircle small sized A and will miss very large sized A

25. Extension of pathology into adjacent temporal lobes
Agnosia – inability to recognize object
Visual , tactile, auditory (sensory input specific )
Prosopognosia – inability to recognize familiar face
- show pictures of familiar and popular personality, animals
Object agnosia – show various objects and ask to identify

26. MMSE Screening test 30 points 5- orientation to time
5- orientation to space
5- attention serial 7 or spell world backwards
3 registration of the 3 items
3 recall
2 naming
3 three stage command
1 for reading
1 for writing 1
1 copying a diagram