molecular mechanisms of behavior formation

Molecular Mechanisms of Behavior Formation

Ed ZiffSkirball Molecular Neuroscience Program

Departmen of Biochemistry

How does the Brain Respond to Information from the Senses to Generate Behavior?

Sight

Hearing

Touch

Taste

Smell

Pain

Balance

SENSES

BEHAVIOUR

Speaking

Walking

Planning

Heart rate

Playing pianoNervousSystem

(memory)

NervousSystem

(memory)

Synapses connect neurons to form circuits

Receptor

Synapse

Direction of signal

Synapses: Sites of Neuron Communication

Vesicle

Synapses connect neurons to form circuits

Synapse

Direction of signal

Neurotransmitter is released

Receptor

Vesicle

Synapses connect neurons to form circuits

Synapse

Direction of signal

Receptors are activated

Receptor

Vesicle

Synapses connect neurons to form circuits

Synapse

Direction of signal

Neuron fires

Receptor

Vesicle

Neuron “Fires”

Synapses connect neurons to form circuits

Synapse

Direction of signal

Receptor

Vesicle

Fire!

Adding Receptors Strengthens Synapses

How do rewards create behavior?

Train rat in cage to drink sucrose

Rat seeks sucrosewhen placed back in

cage

Nucleus accumbens gathers information

SuSu

Collaboration with Dr. Ken Carr, Psychiatry Department

Drinking sucrose

SensoryCortex

VTA

PFC

N Acc

Seeing cageRat

brain

Nucleus accumbens controls prefrontal cortex and behavior

SuSu

Collaboration with Dr. Ken Carr, Psychiatry Department

SensoryCortex

VTA

PFC

N AccRat seeks sucrose

when placed again

in cage

Ratbrain

Seeing cage

Rewards Strengthen Specific Synapses

SuSu

Sucrose

Synapses in nucleus accumbens strengthenWeak Strong

SensoryCortex

VTA

PFC

N Acc

Ratbrain

Collaboration with Dr. Ken Carr, Psychiatry Department

Rat sees cage

Rat seeks sucrose

when placed again in cage

Addictive Behavior Formation•Natural rewards, such as sucrose, strengthen synapses in the nucleus accumbens, a part of the brain’s reward system.•These changes contribute to sucrose-seeking behavior•Similar changes take place during cocaine addiction.•These findings are relevant to the mechanisms of compulsive eating behavior and the epidemic of obesity.

Supported by the NYU Langone Medical Center Center of Excellence on Addiction and the NIH