Why human brain is more intelligent

• Why humans are more intelligent than any other animals on Planet?
• Its 2 important factors - 

1) Larger brain weight to body ratio

2) Immense growth of Association area of human brain

Weight of human brain is 1400g while that of ape is 100g

• Size doesnt matter here.Size of other animals like whale,elephant is more than human brain but they are less intelligent than us.Its weight to body ratio matters

Dissecting highlights on brain :

Brain>>Cerebral hemispheres,brain stem,cerebellum>>gray matter are cell body and white matter are myelinated axons>>nerve fibre bundles>>nerve fibres>>neuron

Association area :(Gray matter)

• It is 6 layered neocortical gray matter 
• Present on lateral surface of cerebral cortex
• Around allocortical and juxtacortcal concentric rings near hilum
• 3 types -

1)Frontal association area : in front of premotor area

2)Parietotemporoccipital area : between somaesthetic area and visual cortex and portion extending to temporal lobe

3)Temporal association area : from lower portion of temporal lobe to limbic cortex

White matter of cerebrum :

• made up of 3 types of fibres-

1)Ariculate/association fibres -

• connects 2 areas in same hemisphere

• 2 subtypes :

a)short association fibres - connects adjacent gyri

b) long association fibres - connects distant areas in same hemisphere

e.g.
• superior longitudinal fasciculus : b/w frontal and temporo-occipital area

• Inferior longitudinal fasciculus : b/w temporal and occipital area

•Cingulate :

•Uncinate fasciculus : b/w anterior pole of temporal lobe and motor speech area

2) Projection fibres - connects CNS to brain stem and spinal cord

3) Commisural fibres - connects 2 areas on different hemisphere

• corpus callosum : connects 2 hemisphere

• parahippocampal : connects hippocampus

• pretectal 

BRAIN FUEL :

• Glucose is primary fuel

• But when glucose is not available brain adapts to use ketones as energy source

• Brain has no energy reserves
(♡ so stupid he is although being called intelligent centre? ♡ No! He doesnt keep reserves to reduce unnecessary load/weight in skull and to unoccupy already limited space in skull)