BIOL 1F25 Lecture Notes - Plantar Reflex
Document Summary
Action potentials in pre-synaptic cell produce action potentials in post-synaptic cell (or. Action potentials in pre-synaptic cell inhibit (slow or stop) the action potentials in the post- synaptic cell. >inhibitory transmitter: gaba; up to 20% of cells in cortex may contain gaba. Signaling within one brain cell: electrical (e. g. action potentials) Nerve cells are signaling units for behavioral responses. Tapping below patella, pulls on tendon and stretches muscle. Knee jerk reflex: monosynaptic circuit (1 synapse); sensory/mns directly connected. Most spinal reflexes are polysynaptic (more than 1 synapse) Reflex networks can also be modified by brain. Stroke foot; normal response is downward response (curling in of toes) Babinski response: upward fanning of toes; seen in infants (up to 2 years) Infant reflex; hidden as we age (inhibited by cortex); can be unmasked by brain trauma, some diseases of ns or excessive alcohol.