Dr Swikruti

Welcome to MBBS Memory Maps in Physiology

Let’s create road-maps for concepts. WISDOM IS NOT A PRODUCT OF SCHOOLING BUT OF THE LIFELONG ATTEMPT TO ACQUIRE IT. –Albert Einstein Hey there! Let’s just say that studying can be fun too. Preparing concept map has been my thing always. So, now I am here to share my view and maps on physiology/medical topicsContinue reading “Welcome to MBBS Memory Maps in Physiology”

DESCENDING MOTOR PATHWAYS / DESCENDING TRACTS

Connect the neurons in, cerebral cortex , Midbrain, Pons, Medulla & Cerebellum with motor neurons (LMN) at various levels. Axons of UMN synapse on spinal : Alpha motor neuron,gamma motor neuron, Spinal interneuron, Sensory afferents TRADITIONALLY TRACTS ARE CLASSIFIED AS: RECENT CLASSIFICATION : Hans Kupyres – 1981,85. CORTICOSPINAL TRACT / PYRAMIDAL TRACT Most important andContinue reading “DESCENDING MOTOR PATHWAYS / DESCENDING TRACTS”

POSTURE & ITS REGULATION

MOTOR CORTEX

PRIMARY MOTOR CORTEX Largest of all motor areas Lies in the precentral Gyrus –> Area 4 of Brodmann extending from medial surface to lateral sulcus. low electrical –> Specific & repeatable movement. HOMONCULUS (little man) –> Drawn by Penfield & Rasmussen 1950. Body is upside down legs most medially pharynx lateral most. SIZE OF REPRESENTATIONContinue reading “MOTOR CORTEX”

ORGANISATION OF MOTOR SYSTEM

NEURAL CONTROL OF MOVEMENT Movement is crucial to all organisms. its performed in higher animals by contraction of & relaxation of the muscles. Motor system exists in Brain to translate out thought, sensation, emotion & feeling into MOVEMENT. SENSORY SYSTEM –> transforms physical energy into neural signals MOTOR SYSTEM –> NEURAL signal is converted toContinue reading “ORGANISATION OF MOTOR SYSTEM”

Basal Ganglia

FUNCTIONS OF BASAL GANGLIA PLANNING & PROGRAMMING –> Discharge starts even before commencement of movement. EXECUTION OF MOTOR TIMING, INTENSITY & SEQUENCES –> Basal Ganglia gets input from cortex projects back to cortex (Prefrontal, premotor, Supplementary motor area). These Corticospinal & Corticobulbar neurons influence Proximal & Distal limb. MUSCLE TONE –> Inhibits tone, decreases stretch reflexContinue reading “Basal Ganglia”