Ascending Tracts of goll and burdach (fasciculus gracilis and fasciculus cutnaeous )

They are also called fasciculus gracilis and fasciculus cunateous 

 SENSATIONS 

• fine touch 
• propioception 
• vibration 
• pressure

PATHWAY

• First-order neuron -
• arises from receptors 

• enters spinal cord through posterior root 

• cell body resides in dorsal root ganglia

• it ascends on the same side to end in the nucleus gracilis and nucleus cutaneous present in the medulla

•  fibres closer to the midline are from the lower parts of the body 

• the lateral fibres are from the upper part of the body 

• Second-order neuron 

• arises from the nucleus gracilis and nucleus cutaneous
• they cross to the opposite side
• ends in the ventral posterolateral nucleus of the thalamus




• Third-order neuron 
• arises from the thalamic nucleus 
• ends in the sensory cortex (areas 3, 1 and 2)

RELAY 

• they have two relays 
• medulla 
• thalamus 

        

IN SHORT 

1. receptor
2. dorsal root ganglia
3. ascending fibres 
4. fasciculus gracilis and fasciculus cutaneous
5. ventral posterolateral nucleus o thalamus 
6. cerebral cortex

FUNCTIONS 

i. Fine (epicritic) tactile sensation

ii. Tactile localization 

iii. two-point discrimination

iv. Conscious kinesthetic sensation 

v. Stereognosis It is also

a synthetic sense produced by a combination of

touch and pressure sensations.

EFFECT OF LESION 

•  Loss of fine tactile sensation; however, crude touch sensation is normal
• Loss of tactile localization
• Loss of two point discrimination
•  Loss of sensation of vibration
• Astereognosis (inability to recognize known objects by touch while closing the eyes)
• Lack of ability to differentiate the weight of different objects
•  Loss of proprioception (inability to appreciate the position and movement of different parts of the body) 
• Sensory ataxia or posterior column ataxia