1. Neuroanatomy for Psychiatrists
Dr Rohit Shankar
MBBS, MD, MRCPsych, CCT, PGC Cl. Research
Consultant in Adult Developmental Neuropsychiatry

2. Why should we know any Neurology?
Brain Behaviour connection
Man made divide
2000 years of togetherness
Hippocrates ( BC) Humours theory and Triad of mental illness
Plato – divine inspired and physical inspired mental illness
Inter canon of the yellow emperor
Johann Christian Reil 1808
Reintegration – biological underpinnings

3. Golden Rules Adhere to the routine
A good History is more useful than a good examination
Usually well practiced testing would take 20 minutes then come back to any areas of deficits
Don’t ‘Scan’ before you ‘Can’ physically examine
Hoof beats are usually more likely to be from horses as opposed to Zebras, Hemiparesis is more likely from a stroke as opposed to an unwitnessed seizure

4. The Neurological Exam Motor System – Limb strength
spasticity, flaccidity and fasciculation
Abnormal movements – e.g.. Chorea and tremors
Reflexes –
DTRs – biceps, triceps, Quadriceps, Achilles
Pathological reflexes – Babinski, frontal release signs
Sensation –
Position, vibration, stereognosis, Pain
Cerebellar –
Finger – Nose, Heel – Toe, Rapid alternating movements, Gait

5. The Neurological Exam Mental Status –
GCS, orientation, Language, higher intellectual functions (arithmetic)
Cranial Nerves –
I Smell
II Visual acuity, visual field, optic fundi
Ocular motility nerves:
III,IV,VI pupil size and reactivity, extra ocular motion
cerebello-pontine angle nerves:
V corneal reflex and facial sensation
VII upper and lower facial muscle strength, taste
VIII hearing
Others:
IX - XI articulation, palate movement, gag reflex
XII tongue movements

6. THE LAST SUPPER

7. DETAILS LIE IN BEHOLDER’S OBSERVATIONS!
Detail of the Da Vinci's The Last Supper by Giacomo Raffaelli

8. Diagnostic Pathway Be Ritualistic The formulation:
Symptoms, Signs, Localization and Diagnosis
Localization:
Where is the lesion?
CNS, PNS or Muscles
What is the lesion?
Diffuse or Discrete
Diagnosis:
Common conditions arise commonly –
Hoof beats are usually more likely to be from horses as opposed to Zebras
Hemiparesis is more likely from a stroke as opposed to an unwitnessed seizure

9. The Lobes

10. Job Allocation

11. Division of Labour

12. Lobe Function

14. Frontal Lobe Dysfunction
The primary motor cortex
Contra lateral motor control
The medial frontal cortex
Arousal and motivation – Abulic (Apathy & inattention)
The orbital frontal cortex
Modulate Behaviour -Labile, euphoric, facetious, vulgar
The left postero-inferior frontal cortex (Broca's)
Language – expressive Aphasia
The dorsolateral frontal cortex
Working memory & dysexecutive syndrome

16. Parietal Lobe Dysfunction
The primary somatosensory cortex
Integrates somesthetic stimuli for recognition and recall of form, texture, and weight - Contralateral astereognosis
Posterolateral - Postcentral gyrus
visual-spatial relationships and proprioception
Midparietal lobe (dominant)
calculation, writing, left-right orientation, and finger recognition - Gerstmann's syndrome
The nondominant parietal lobe
Contralateral environmental awareness, drawing – Anosognosia, Hemiasomatognosia, spatial Apraxia

17. Temporal Lobe Dysfunction
Auditory perception, receptive components of language, visual memory, declarative (factual) memory, and emotion
Right temporal lobe lesions - interpret nonverbal auditory stimuli (e.g. music)
Left temporal lobe lesions interfere greatly with the recognition, memory, and formation of language
medial limbic - emotional parts & TLE

18. Occipital Lobe Dysfunction
Primary visual cortex and visual association areas
Anton Babinski Syndrome
Occipital Seizures – C/L Visual Hallucination
Prosopagnosia - Face blindness

19. Conscious pain, temperature, crude touch & pressure
Lateral and an anterior tract
Thalamus (all conscious sensations) projection to areas of the cerebral cortex

20. This tract carries unconscious proprioception (muscle sense) to the cerebellum which is responsible for muscle coordination They innervate the cerebellum on the same side

21. Corticospinal tract cerebral cortex – Localised voluntary motor control Two branches, the lateral and the anterior The lateral crosses in the medulla at the ‘pyramids’ The anterior does not cross Common signs: DTR abnormalities, Motor Paresis, Babinski

22. The Basal Ganglia Located Sub cortically
Modulates the Corticospinal tract
Regulates muscle tone, motor activity and generates postural reflex
Confined to the brain, no role on LMNs or Spinal Cord
Caudate Nucleus, Corpus Striatum, Lentiform Nucleus (Globus Pallidus + Putamen), Subthalamic Nuclei, Substantia Nigra

23. IC (white matter) runs between the CN and the LN = Corpus Striatum
Artery of Stroke
Pure damage to Basal Ganglia = No corticospinal symptoms, No neuropsychological dysfunction, No cognitive Dysfunction, contra lateral
Result of biochemical not usually structural, B/L, slow progress
Cerebrum + BG = inv Mov + cognitive &/or psychiatric Sx

24. Basal Ganglia and Limbic System

25. Hippocampal Formation & Amygdala
Dentate gyrus + the hippocampus proper + Subiculum
Memory, spatial navigation and attention
Amygdala
Via hypothalamus activates the ANS
Activation of Neurotransmitters
Emotional Learning – Conditioning
Memory modulation
Kluver Bucy Syndrome – Docility: diminished fear responses, dietary changes, Hyperorality, Hypersexuality, Visual Agnosia, Hypermetamorphosis: irresistible impulse to notice and react to everything, memory loss

26. Papez Circuit

27. Function of the Limbic System
Affective functions
Playful moods
Emotions and feelings, like wrath, fright, passion, love, hate, joy and sadness
self preservation

28. Dopamine Pathways HT
VTA

29. Serotonin Pathways

30. Serotonin and Depression
Serotonin transmission - Caudal raphe nuclei and Rostal raphe nuclei is reduced in depression
Increasing the levels of serotonin in these pathways, by reducing serotonin reuptake = treatment

31. Serotonin in Schizophrenia
Dorsal raphe nuclei - Substantia Nigra
Rostral raphe nuclei - cerebral cortex, limbic regions and basal ganglia
The up-regulation of Serotonin pathways leads to the hypofunction dopamine pathways = negative symptoms
The serotonergic nuclei in the brainstem that give rise to descending serotonergic axons remain unaffected in schizophrenia

32. Serotonin and Depression

33. Serotonin and Schizophrenia

34. Brain Stem Brain Stem: Midbrain, Pons, Medulla
Contains CNs, CS Tract and other ‘long’ Tracts
Positive evidence of localization and negative evidence of cerebral injury
Example – Diplopic but no effect on visual acuity or fields
Brain stem injures -Massive infarcts, Overdoses etc
Simultaneous damage of BS and Cerebrum RARE exceptions: MS, tumours etc

35. Cerebellum Controls the coordination of movements/limbs – Ipsilateral
Muscle Hypotonia and Pendular DTRs
No obvious cognitive role
Intentional Tremor
Gait Ataxia, Scanning speech, tandem gait failure
Cognitive Impairment?
Alcohol – Thiamine, AIDS, toxins, Vitamin E, Phenytoin

36. Psychiatry and Neurology
Psychogenic Paresis and Hoover’s Sign
La Belle Indifference MS
Sleep Disorders
Parkinsonism, Huntington, Wilson’s disease
Frontal Lobe issues, Dementia
Seizures of Non epileptic origin and NEADs, Sensory seizures

37. CASE STUDY 1
An elderly man has left ptosis and a dilated and unreactive left pupil with external deviation of the left eye, right hemiparesis, right sided hyperactive DTRs and positive Babinski, no aphasia or hemianopia where is the lesion?
Cerebrum
Cerebellum
Pons
Midbrain
Medulla
None of the above

38. CASE STUDY 2
A 20 year old woman reports having lost all vision in her right eye and right hemi-sensory loss. Pupil and DTRs are normal. She does not press down with her left leg while attempting to lift her right leg. where is the lesion?
Cerebrum
Cerebellum
Pons
Midbrain
Medulla
None of the above

39. CASE STUDY 3
50 yr old man with mild dementia has absent reflexes, loss of position and vibration sense and ataxia. Which areas are affected?
The CNS
The CNS and the PNS
The Cerebrum and the posterior columns
The ANS

40. CASE STUDY 4
After having suffered from increasing severe depression for 3 years the psychiatrist finds the 55 year old woman to have right sided optic atrophy and left sided papilledema. Where is the lesion?
Occipital Lobe
Frontal Lobe
Parietal Lobe
Temporal Lobe
None of the above

41. QUESTION
Where is the primary damage in Wilson's disease, Huntington's Chorea and Choreiform Cerebral Palsy?
Extra pyramidal system
Pyramidal system
Entire CNS
Cerebellar outflow tracts
None of the above

42. SOME CORRECTIONS
EMI -2