The neocortex have 6 layers and allocortex have only 3 layers. The 6 layers of Neocortex: Orientation of layers: Outer: Towards meaninges Inner: Towards white matter Idea about the layers: Molecular or plexiform: Only cell processes Granular layer: Densely packed stellate cells Pyramidal layer: Medium and Large pyramidal cells Multiform…
Tag: Nervous system
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Internal Capsule Simplified
Internal Capsule is a “boomerang” shaped (on horizontal section) and “funnel” shaped, i.e. tapering from superior to inferior (on sagittal section) white matter structure sandwiched between: Medially: Head of Caudate nucleus and Thalamus Laterally: Lenticular nucleus (Globus pallidus and Putamen) Parts of Internal Capsule 1. Anterior limb: Carries fibers to…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Limbic System Simplified
Limbic system is complex both structurally and functionally. It is located on either side of the thalamus, immediately below the cerebrum and consists of both the grey mater and white mater. Let us simplify the structure of limbic system: Hypothalamus is central to the limbic system Limbic cortex: 2 “C”…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Visual Pathway : Supplement Knowledge
Everyone must be aware of the normal visual pathway and their defects. Here, I’ve tried to enlist the topics related to the visual pathway that are “nice to know” but you may have missed it or failed to understand properly. Below is the basic visual pathway: Wilbrand’s knee Anterior…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Retinal Layers Simplified
The ten layers of retina – this microscopic anatomy is frequently asked in examinations and also important from the physiological viewpoint. There are plenty of mnemonics around the web, but we will proceed in a different approach to remember the 10 retinal layers easily. A. Retina is 3 neuron system…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Nuclei of Hypothalamus – Mnemonic
Hypothalamus is composed of several nuclei with different important functions – hence, it is important and confusing at the same time. I have devised a pictorial or visual mnemonic to make things easier for you. Hypothalamus is a Cow Imagine a Crying and Farting Cow when recalling the Hypothalamus. Preoptic:…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Basal Ganglia Pathways Simplified
The combination of excitatory and inhibitory signals in the basal ganglia circuit is pretty confusing. Let’s break the circuit and make them easy to understand. There are 2 pathways in Basal ganglia circuit: Excitatory pathway Inhibitory pathway Let’s declare 2 things first: Dopaminergic nigrostriatal projection increases motor activity. Cholinergic striatal…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Vertebrobasilar Arterial System and Syndromes Simplified
Vertebral Artery I use the analogy of hand to remember the vertebral artery and it’s branches: Origin: Branch of subclavian arteries Course: Ascends through transverse foramina on C6 through C1 and enters posterior fossa through foramen magnum Continue up the ventral surface of medulla Converge at the ponto-medullary junction to form…