Body part: Rostral- forward-towards face. Caudal- like a tail, back. Dorsal- Back up, like a dolphin. Ventral- Belly down. Location: Anterior- front. Posterior- back. Lateral- sides. Medial- middle. Brian sections: Coronal- down the middle, ear to ear. Horizontal- front to back. Sagittal- middle. Central
Nervous system: Bone- skull Meninges- cartilage that protects brain. Cerebral spinal fluid- cushions brain. Blood brain barrier brings blood but doesn’t touch neurons. Gray Matter- gray brown color from blood vessels and neuronal cell bodies. White matter- White color from axons covered in an
insulating layer of glial cells. Neurons- communicate with other neurons- fire or don’t fire. Dendrites: receive info. Terminal button: end of axon where info sends. Synapse- empty space between neurons axon and dendrite. Neurotransmitters- gets sent across synapse. Cell membrane- keep
everything in ie. Skin. Cell membrane: acts as a gate keeper. Intercellular (inside cell) extracellular (outside cell). Regulates movement of substances. Regulates concentration of salts and other chemicals. Phospholipid bilayer- Head- contains phospholipids, polar, hydrophilic. Tail- lipid molecules, no
polarity, hydrophobic. Impermeable, only nonpolar molecules like oxygen and carbon dioxide can pass through phospholipid bilayer. Ions: Charged particles, positive or negative. Cannot freely enter the cell due to polar surface, blocked, bound, repelled. substances cross membrane? Embedded
proteins act as a gate to provide influx and efflux to substances. Channels- create certain sized hole. Gates: can change shape to sometimes allow certain ions under certain conditions. Passive ions flow in and out depending sometimes its closed. Pumps: active form of transportation, shape changing,
push certain ions out, pull some in. Parts of the brain- basic functions Hindbrain: Cerebellum (balance) • Reticular formation (alert) • Pons (breathing, sleep, etc) • Medulla (breathing, sleeping, etc) Midbrain: Tectum (visual and auditory input) Tegmentum • Substantia nigra Diencephalon:
Hypothalamus (motivation) Epithalamus/pineal gland (hormones) Thalamus (sensory relay) Forebrain- Three main structures – Basal Ganglia (movement) • Putamen • Globus Pallidus • Caudate Nucleus – Limbic System • Amygdala (emotion) • Hippocampus (memory) • Cingulate Cortex (error
detection) Neocortex/cerebral cortex – Has expanded the most during evolutionary process – Comprises 80% of the human brain, unique to mammals. – 2.7 square feet, thickness of 1.5–3.0 millimeters – Six layers – Two cerebral hemispheres – Four lobes: Frontal Lobe- Motor functions. Parietal lobe
– Body senses. Temporal lobe – Auditory functions Occipital lobe – Visual functions. The synapse: Presynaptic membrane- membrane on the axon terminal. Synaptic cleft: space between the axon terminal and dendritic spine. Postsynaptic membrane: Membrane on dendritic spine. Synaptic vesicles
and storage granules: located inside the axon terminal, contain the neurotransmitter. POTENTIALS: Negative potential: Outside is more positive than inside. Resting potential: Baseline, neuron isn’t firing. -70MV, more positive outside and negative inside. Determined by concentration. Action
potential: when a large, graded potential that causes depolarization occurs. Membrane must reach threshold at -50 mv. Hyperpolarization: More negative, potassium leaves, chloride enters. Over polarized, dips down on graph. Depolarization: less negative, sodium is let in, makes a hill on graph.
Concentration gradient: chemical. Electrical gradient: voltage. Ions are repelled by like ions (battery) cations (positive charge) Potassium (K+) Sodium (Na+) Calcium (Cass++) Anion: negative. Chloride (Ch-) Random ions (A-) . A-Ions and K+ ions, random ions, and potassium ions, have a higher
concentration inside of axon. CL- and Na+ ions, Chloride and Sodium ions, more concentrated outside the axon Relative refractory: Cell is more negative than threshold, more difficult to get it to threshold because its so negative. Myelination: Transmission needs to be fast (activity) Myelin sheath-
insulation around axon. Nodes of Ranvier: uninsulated regions between the myelinated segments. Voltage sensitive ion channels. Steps in neurotransmission: 1. Synthesis- neurotransmitter is created, stored in synaptic vesicles. 2. Release- triggered by AP- lets ca+ into axon. Transmitters is let out for
swim across synaptic cleft- exocytosis. 3. Receptor action- release of one vesicle- one quantum. Transmitter interacts with target cell receptor, hyperpolarizes, depolarizes. 4. Inactivation- diffusion, degradation, reuptake, or glial cells dispose of. Type 1: excitatory. Type 2: inhibitory. To be a
neurotransmitter: 1. Chemical must be synthesized in or be present in the neuron. 2. Chemical must be released when the neuron is active and produce a response in some target 3. The same response must be obtained when the chemical is experimentally placed on the target. 4. A mechanism for
deactivating the chemical must exist. Small molecule neurotransmitters: small organic molecules. Synthesized and packaged in axon terminals. Derived form the food we eat. Quick acting, rate limiting factor. Amines- dopamine, norepinephrine. Epinephrine, serotonin. Amino acids: glutamate,
gamma aminobutyric acid (Gaba) glycine. Peptide transmitters: Neuropeptides- multifunctional chains of amino acids made by the cells DNA. Peptide transmitters: serves as hormones, activate in response to stress, encourage mother child bonding, facilitate learning, regulate eating and drinking,
respond to pleasure and pain. Transmitter gases: synthesized as needed by the cell. Can be produced in many regions of the cell. Diffuse away from the cell after production. Nitric oxide (NO) Controls muscles in intestinal walls. Dilates blood vessels in the brain and genital organs. Viagra- acts by
enhancing action of NO. Types of drugs: Group 1: sedatives & antianxiety: Alcohol and barbiturates (GABA) Benzodiazepines (GABA) Group 2: antipsychotics: First generation butyrophenones and phenothiazines. Second generation antipsychotics ( blocks serotonin receptor) Group 3: antidepressants:
Monoamine oxidase inhibitors (block serotonin breakdown) Selective serotonin reuptake inhibitors (blocks serotonin reuptake) Group 4: Opiod analgesics: Synthetic opioids- heroin, affect mu receptors (morphine/codeine) endorphins are produced by your body and act on mu receptors. Nalorphine
and naloxone (Narcan, nalone) are competitive inhibitors. Group 5: Psychotropics: block DA reuptake (cocaine and amphetamines) Group 6: Psychedelics and hallucinogens: acetylcholine psychedelics (nicotine) Glutamate psychedelics: ketamine. Norepinephrine psychedelics (mescaline) Anandamide
psychedelics: Tetrahydrocannabinol. Serotonin psychedelics (LSD/MDMA). ). Activating systems: Cholinergic system: Normal waking behavior and memory. Dopaminergic system- nigrostriatal pathway- movement. Mesolimbic pathway- pleasure. Noradrenergic system- learning and emotions.
Serotonergic system: waking pattern, learning, emotion. HPA axis: Hypothalamic pituitary adrenal axis- fast and slow systems using epinephrine (fast) and cortisol (Slow) Reduce energy and protein stores. Growth hormone + reproductive processes inhibited. Immune system and digestion
suppressed. Hippocampus detects cortisol and tells hypothalamus to turn it off but can be damaged by chronic stress. Hormones: Produced in hypothalamus -> pituitary gland -> endocrine glands -> blood stream. Steroid hormones: sex/gonadal hormones. Stress hormone- glucocorticoid (slow
system) Act on adrenal gland. Peptide hormones- homeostasis. Agonists: Drugs that increase the effectiveness of neurotransmission. Antagonists- drugs that decrease the effectiveness of neurotransmission. Addiction and dependence: Substance abuse -> substance dependence. Withdrawal
symptoms- because of the physical changes in the brain. Ex: alcohol withdrawal and Gaba. Drug use hypothesis: Dependence hypothesis: Hedonic hypothesis: Insensitive sensitization theory. Genetic component.
2 Vision: Light is converted into chemical energy in the photoreceptors, and this is converted into action potentials. Photoreceptors- a type of sensory receptors. Located in the retina. (the very back of the eyeball) Rods- sensitive to dim light, night vision. Located in the peripheral retina.
Cones- Sensitive to bright light, day vision, and color vision. Densely packed in the fovea- center of the retina. Light goes through the eye, to the retina, stimulates photoreceptors- rods and cones, then communicates via bipolar cells and ganglion cells, sending action potential towards the front of the
eyeball. Then goes to the optic nerve- axons on a bunch of cells that carry info out of the eyeball. Crossing the optic chiasm- optic nerves leave the eye causing a blind spot. Information from the right visual field of the right eye and the left visual field of the left eye crosses the optic chiasm. Visual
fields are processed in different hemispheres. Audition: Aire pressure waves are converted into mechanical energy, which activates the auditory receptor cells, producing action potentials. Auditory receptors- detect the frequency, amplitude, and complexity of air pressure waves.. Sound waves enter
the ear, go to the outer ear, to the middle ear, where we have the cochlea that contains receptors that transduce info from soundwaves into mechanical waves that turn into action potentials. Idle ear- eardrum and ossicles. Hair cells in the cochlea on the basilar membrane, get stimulated by changes
in air pressure, create action potentials that go from the auditory nerve to midbrain and thalamus, to the auditory cortex, part of the temporal lobe. The frequency of the sound is transduced by the basilar membrane. It’s thick at the base, tuned for high frequency. Thin and wide at the apex, tuned
for low frequencies. Tonotopic representation, where the hair cells are stimulated, tells us about the tone being picked up on. Olfactory: Chemical molecules in the air and food fit into receptors and activate action potentials. Somatosensory: activates mechanoreceptors that generate action
potentials. Tissue damage releases a neurotransmitter that activates pain fibers and produces action potentials. 4 major categories: nociception- slow unpleasantness, pain, itching heat. Hapsis- Fast fine touch or pressure. Proprioception- body location/movement. Balance- vestibular system. Two
pathways: Ventral: nociception. Pain response. The slower system, use interneurons. Dorsal: hapsis and proprioception: fast system Both end up in the primary somatosensory cortex. Somatosensory cortex: Homunculus- diff parts of your body are represented to differing degrees in the
somatosensory cortex. Sensory to touch, lots of receptors, over-represented in somatosensory cortex. Vestibular system: part of the somatosensory system. Located in the inner ear. Allows us to perceive our own motion and to maintain balance Gustatory- diff types of receptors that respond to
salty, sour, sweet, bitter, anomy. Affected by age, condition, and genetics. Axons of olfactory receptor relay synapse in the olfactory bulb. Bulbs’ major output is the lateral olfactory tract, it passes ipsilaterally to the pyriform cortex, the amygdala, and the entorhinal cortex. Smells and
memories/emotions = so close to the limbic system Visual pathways: Basic pathways and areas involved: Geniculostriate pathway- basic vision pathway. From the eye, through the optic tract, the lateral geniculate nucleus (thalamus), sent to the striate cortex of the occipital lobe, moves through the
occipital lobe to be processed in other areas. The conscious vision that we are aware of. Secondary visual pathway: Tectopulvinar pathway: brain stem to the thalamus, unconscious. visual information goes from the eye, through the optic tract, to the superior colliculus (midbrain), to the posterior
part of the thalamus, the pulvinar, then to other visual cortical areas. Not aware of, fish and animals rely on this pathway. If we have damage to the first pathway, but we still have this pathway, then we have blindsight. Ability to react to visual stimuli without being conscious of it. Sensory receptor
neurons communicate to the cortex via several connecting interneurons. Relays allow sensory systems to produce relevant actions. Identify change- rapidly vs slowly adapting. Identify the presence of a stimulus. Identify self vs other- exteroceptive: outside vs interoceptive-inside.Density determines
sensitivity. Touching a stove: Pain receptors in the spinal cord trigger reflexes that produce withdrawal movements. Pain pathways in the periaqueductal gray matter (PAG) trigger behavioral activation, emotional responses, and longer-lasting pain. Cortex identifies the felt pain, its external cause, and
possible remedies. Also, helps us adapt our experience. Sensation= objective. Perception= subjective. . Chapter 9: Motor Systems Basic pathways and areas involved: send efferent information from most posterior part of the frontal lobe M1, which tell muscles to contract. Citicoline is released, tells
muscle fibers to contact. 1: Primary motor cortex: bark over the brain. A strip of cortex that is important for voluntary movement. The only region that can evoke movement. Basal Ganglia: Modulating movement. Volume control, making sure movement is appropriate for the circumstance. The
subcortical structure must cut the brain open to see. Projections from substantia nigra (midbrain) Dopaminergic system- Niagara striatal is important for controlling movement Disorders include Huntington-hyperkinetic disorders, Tourette’s-hyperkinetic disorders, Parkinson’s-hypokinetic disorder.
Cerebellum: Balance gets information from proprioception- where we are in space. Important for motor learning, timing, and accuracy. Classical conditioning happens here. Adaptation too; our brain adapts and compensates. Spinal cord: Important for voluntary movement. Travel from the brain
down the spinal cord to activate muscles. Pyramid cells in the cortex project to the brainstem and spine. Natural movements: prewired movement, we do a lot. Graziano’s research: preprogrammed shortcut to enact certain movement. Each representation of the body is responsible for a somewhat
different movement. We can represent specific natural movements in our cortex. Instead of each movement being pieced together, we have shortcuts. Whole body movements (more complex) represented in the premotor cortex; more discrete (less complex) movements in the motor cortex. Mirror
neurons: goal-oriented movement. generally located in the left hemisphere, in the premotor cortex. Active when you watch someone else move. \Have a role in self-action, perception of action, self-awareness, and awareness of the intention and actions of others. Important for gestures and verbal
language. Fewer mirror neurons- struggle with empathy. Autism disorders are where we see diff mirror neurons. the suspense is goal-oriented.
3 Long-term potentiation: change in an action potential that lasts. cells that fire together, wire together. Persistent strengthening of synaptic connections between neurons in response to activity. Memories create physical changes in the brain. Change in presynaptic cell- changes in calcium
channels and in the postsynaptic cell- more receptors for the neurotransmitters, or more dendrites - happens because of calcium channels. An action potential reaches the terminal, calcium channels open and signal for the neurotransmitter to be released. Also with plasticity, change in the brain in
response to experience or learning. Explicit: Episodic memory: autobiographical experience, has a place in time. Contributes to autonoetic awareness. G>O> case study -> KC couldn’t remember past personal experiences or imagine the future. Explicit: Conscious Explicit: Semantic memory:
facts/knowledge. Nonautobiographical knowledge. Intact in HM and other patients with ventral prefrontal and medial temporal lobe damage. Implicit memory: unconsciousness. skills, habits, priming, conditioning. Memory of learned skills or reactions that are unconscious. Emotional; conscious and
unconscious. attraction, avoidance, fear. Involves the amygdala. Both implicit and explicit aspects of memory. Short term/working memory: things like rehearsal. Sensory ex: habituation, motor, cognitive. Frontal lobe – dorsolateral prefrontal cortex 3 theories of memory: System consolidation
theory: role of the hippocampus is to consolidate memories, making them permanent, hold them for a time, and send them to be stored elsewhere in the brain. Accounts for the preservation of old memories. Multiple trace theory: memory rarely consists of a single trace or neural substrate, when
we have brain damage, we don’t lose all memory is stored and dispersed across the brain. Reconsolidation: each time a memory is used, it is reconsolidated. A memory enters a liable phase when its recalled and is then restored as a new memory. Results in many different traces for the same event.
Temporal/Rhinal cortex- around hippocampus in medial temporal lobe. Hippocampus- medial structure, not cortex. Subcortical. Surrounded by cortex- perirhinal. Rhinal cortex that surrounds the hippocampus. Damage to the hippocampus produces impairment when the task includes context.
Damage to the rhinal cortex produces severe anterograde/retrograde impairments on object recognition tests. Seahorse shape. Important for creating new memories =. Ventral: “Vut” Uncinate fasciculus: white matter tract, myelinated axons of a neuron. connecting frontal and temporal lobe.
Important for memory, communication is important for memory formation and retrieval. Amnesias- retrograde- old, previous to an accident, unable to have old memories. Anterograde- unable to form new memories, maintain old memories. infantile- can’t form early episodic memories, like
childhood memories. – because we don’t have language before then? Maybe because of synaptic pruning? Fugue: dissociative. Don’t know what happened for a brief period of time: blackout drunk. Laterality: Right temporal cortex: Deficits in face recognition, spatial position, maze learning. Left
temporal cortex: Deficits in word lists, nonspatial association, recurring digits test. Right prefrontal cortex: retrieval. Left prefrontal cortex: encoding. Language: Continuity: developments in language, language has continuously evolved. Discontinuity: it’s a big jump from nonhuman ancestors to
human language speech. Only humans can do it. Ape: learned complex language communication skills. Can learn human-like language even though they don’t have vocal cords using the core skills. Parrot: does have vocal cords and tongue, can create compound words. The parrot was trained to do
complex problem solving and create new sentences and answer new problems that he had never been exposed to. FOXP2 gene- discontinuity hypothesis: genetic allele that is associated with changes in articulation- how we move our mouth and lips to make speech sounds. Gene that was mutated
people have severe speech Impediments. Discovered because the family in the UK had a genetic family-wide pattern of severe speech. found a mutation in their FOXP2 gene. The genetic mutations at the level of the genome, the nucleus, leads to differences in the brain area, there is dispersed
activity all over the cortex for people with mutation. For people who don’t have the mutation, their activation during speech task is in the frontal lobe called Broca’s area- associated with the production of speech – left hemisphere. Core skills- Categorization/schemas: must be able to have broad
Nervous system: Bone- skull Meninges- cartilage that protects brain. Cerebral spinal fluid- cushions brain. Blood brain barrier brings blood but doesn’t touch neurons. Gray Matter- gray brown color from blood vessels and neuronal cell bodies. White matter- White color from axons covered in an
insulating layer of glial cells. Neurons- communicate with other neurons- fire or don’t fire. Dendrites: receive info. Terminal button: end of axon where info sends. Synapse- empty space between neurons axon and dendrite. Neurotransmitters- gets sent across synapse. Cell membrane- keep
everything in ie. Skin. Cell membrane: acts as a gate keeper. Intercellular (inside cell) extracellular (outside cell). Regulates movement of substances. Regulates concentration of salts and other chemicals. Phospholipid bilayer- Head- contains phospholipids, polar, hydrophilic. Tail- lipid molecules, no
polarity, hydrophobic. Impermeable, only nonpolar molecules like oxygen and carbon dioxide can pass through phospholipid bilayer. Ions: Charged particles, positive or negative. Cannot freely enter the cell due to polar surface, blocked, bound, repelled. substances cross membrane? Embedded
proteins act as a gate to provide influx and efflux to substances. Channels- create certain sized hole. Gates: can change shape to sometimes allow certain ions under certain conditions. Passive ions flow in and out depending sometimes its closed. Pumps: active form of transportation, shape changing,
push certain ions out, pull some in. Parts of the brain- basic functions Hindbrain: Cerebellum (balance) • Reticular formation (alert) • Pons (breathing, sleep, etc) • Medulla (breathing, sleeping, etc) Midbrain: Tectum (visual and auditory input) Tegmentum • Substantia nigra Diencephalon:
Hypothalamus (motivation) Epithalamus/pineal gland (hormones) Thalamus (sensory relay) Forebrain- Three main structures – Basal Ganglia (movement) • Putamen • Globus Pallidus • Caudate Nucleus – Limbic System • Amygdala (emotion) • Hippocampus (memory) • Cingulate Cortex (error
detection) Neocortex/cerebral cortex – Has expanded the most during evolutionary process – Comprises 80% of the human brain, unique to mammals. – 2.7 square feet, thickness of 1.5–3.0 millimeters – Six layers – Two cerebral hemispheres – Four lobes: Frontal Lobe- Motor functions. Parietal lobe
– Body senses. Temporal lobe – Auditory functions Occipital lobe – Visual functions. The synapse: Presynaptic membrane- membrane on the axon terminal. Synaptic cleft: space between the axon terminal and dendritic spine. Postsynaptic membrane: Membrane on dendritic spine. Synaptic vesicles
and storage granules: located inside the axon terminal, contain the neurotransmitter. POTENTIALS: Negative potential: Outside is more positive than inside. Resting potential: Baseline, neuron isn’t firing. -70MV, more positive outside and negative inside. Determined by concentration. Action
potential: when a large, graded potential that causes depolarization occurs. Membrane must reach threshold at -50 mv. Hyperpolarization: More negative, potassium leaves, chloride enters. Over polarized, dips down on graph. Depolarization: less negative, sodium is let in, makes a hill on graph.
Concentration gradient: chemical. Electrical gradient: voltage. Ions are repelled by like ions (battery) cations (positive charge) Potassium (K+) Sodium (Na+) Calcium (Cass++) Anion: negative. Chloride (Ch-) Random ions (A-) . A-Ions and K+ ions, random ions, and potassium ions, have a higher
concentration inside of axon. CL- and Na+ ions, Chloride and Sodium ions, more concentrated outside the axon Relative refractory: Cell is more negative than threshold, more difficult to get it to threshold because its so negative. Myelination: Transmission needs to be fast (activity) Myelin sheath-
insulation around axon. Nodes of Ranvier: uninsulated regions between the myelinated segments. Voltage sensitive ion channels. Steps in neurotransmission: 1. Synthesis- neurotransmitter is created, stored in synaptic vesicles. 2. Release- triggered by AP- lets ca+ into axon. Transmitters is let out for
swim across synaptic cleft- exocytosis. 3. Receptor action- release of one vesicle- one quantum. Transmitter interacts with target cell receptor, hyperpolarizes, depolarizes. 4. Inactivation- diffusion, degradation, reuptake, or glial cells dispose of. Type 1: excitatory. Type 2: inhibitory. To be a
neurotransmitter: 1. Chemical must be synthesized in or be present in the neuron. 2. Chemical must be released when the neuron is active and produce a response in some target 3. The same response must be obtained when the chemical is experimentally placed on the target. 4. A mechanism for
deactivating the chemical must exist. Small molecule neurotransmitters: small organic molecules. Synthesized and packaged in axon terminals. Derived form the food we eat. Quick acting, rate limiting factor. Amines- dopamine, norepinephrine. Epinephrine, serotonin. Amino acids: glutamate,
gamma aminobutyric acid (Gaba) glycine. Peptide transmitters: Neuropeptides- multifunctional chains of amino acids made by the cells DNA. Peptide transmitters: serves as hormones, activate in response to stress, encourage mother child bonding, facilitate learning, regulate eating and drinking,
respond to pleasure and pain. Transmitter gases: synthesized as needed by the cell. Can be produced in many regions of the cell. Diffuse away from the cell after production. Nitric oxide (NO) Controls muscles in intestinal walls. Dilates blood vessels in the brain and genital organs. Viagra- acts by
enhancing action of NO. Types of drugs: Group 1: sedatives & antianxiety: Alcohol and barbiturates (GABA) Benzodiazepines (GABA) Group 2: antipsychotics: First generation butyrophenones and phenothiazines. Second generation antipsychotics ( blocks serotonin receptor) Group 3: antidepressants:
Monoamine oxidase inhibitors (block serotonin breakdown) Selective serotonin reuptake inhibitors (blocks serotonin reuptake) Group 4: Opiod analgesics: Synthetic opioids- heroin, affect mu receptors (morphine/codeine) endorphins are produced by your body and act on mu receptors. Nalorphine
and naloxone (Narcan, nalone) are competitive inhibitors. Group 5: Psychotropics: block DA reuptake (cocaine and amphetamines) Group 6: Psychedelics and hallucinogens: acetylcholine psychedelics (nicotine) Glutamate psychedelics: ketamine. Norepinephrine psychedelics (mescaline) Anandamide
psychedelics: Tetrahydrocannabinol. Serotonin psychedelics (LSD/MDMA). ). Activating systems: Cholinergic system: Normal waking behavior and memory. Dopaminergic system- nigrostriatal pathway- movement. Mesolimbic pathway- pleasure. Noradrenergic system- learning and emotions.
Serotonergic system: waking pattern, learning, emotion. HPA axis: Hypothalamic pituitary adrenal axis- fast and slow systems using epinephrine (fast) and cortisol (Slow) Reduce energy and protein stores. Growth hormone + reproductive processes inhibited. Immune system and digestion
suppressed. Hippocampus detects cortisol and tells hypothalamus to turn it off but can be damaged by chronic stress. Hormones: Produced in hypothalamus -> pituitary gland -> endocrine glands -> blood stream. Steroid hormones: sex/gonadal hormones. Stress hormone- glucocorticoid (slow
system) Act on adrenal gland. Peptide hormones- homeostasis. Agonists: Drugs that increase the effectiveness of neurotransmission. Antagonists- drugs that decrease the effectiveness of neurotransmission. Addiction and dependence: Substance abuse -> substance dependence. Withdrawal
symptoms- because of the physical changes in the brain. Ex: alcohol withdrawal and Gaba. Drug use hypothesis: Dependence hypothesis: Hedonic hypothesis: Insensitive sensitization theory. Genetic component.
2 Vision: Light is converted into chemical energy in the photoreceptors, and this is converted into action potentials. Photoreceptors- a type of sensory receptors. Located in the retina. (the very back of the eyeball) Rods- sensitive to dim light, night vision. Located in the peripheral retina.
Cones- Sensitive to bright light, day vision, and color vision. Densely packed in the fovea- center of the retina. Light goes through the eye, to the retina, stimulates photoreceptors- rods and cones, then communicates via bipolar cells and ganglion cells, sending action potential towards the front of the
eyeball. Then goes to the optic nerve- axons on a bunch of cells that carry info out of the eyeball. Crossing the optic chiasm- optic nerves leave the eye causing a blind spot. Information from the right visual field of the right eye and the left visual field of the left eye crosses the optic chiasm. Visual
fields are processed in different hemispheres. Audition: Aire pressure waves are converted into mechanical energy, which activates the auditory receptor cells, producing action potentials. Auditory receptors- detect the frequency, amplitude, and complexity of air pressure waves.. Sound waves enter
the ear, go to the outer ear, to the middle ear, where we have the cochlea that contains receptors that transduce info from soundwaves into mechanical waves that turn into action potentials. Idle ear- eardrum and ossicles. Hair cells in the cochlea on the basilar membrane, get stimulated by changes
in air pressure, create action potentials that go from the auditory nerve to midbrain and thalamus, to the auditory cortex, part of the temporal lobe. The frequency of the sound is transduced by the basilar membrane. It’s thick at the base, tuned for high frequency. Thin and wide at the apex, tuned
for low frequencies. Tonotopic representation, where the hair cells are stimulated, tells us about the tone being picked up on. Olfactory: Chemical molecules in the air and food fit into receptors and activate action potentials. Somatosensory: activates mechanoreceptors that generate action
potentials. Tissue damage releases a neurotransmitter that activates pain fibers and produces action potentials. 4 major categories: nociception- slow unpleasantness, pain, itching heat. Hapsis- Fast fine touch or pressure. Proprioception- body location/movement. Balance- vestibular system. Two
pathways: Ventral: nociception. Pain response. The slower system, use interneurons. Dorsal: hapsis and proprioception: fast system Both end up in the primary somatosensory cortex. Somatosensory cortex: Homunculus- diff parts of your body are represented to differing degrees in the
somatosensory cortex. Sensory to touch, lots of receptors, over-represented in somatosensory cortex. Vestibular system: part of the somatosensory system. Located in the inner ear. Allows us to perceive our own motion and to maintain balance Gustatory- diff types of receptors that respond to
salty, sour, sweet, bitter, anomy. Affected by age, condition, and genetics. Axons of olfactory receptor relay synapse in the olfactory bulb. Bulbs’ major output is the lateral olfactory tract, it passes ipsilaterally to the pyriform cortex, the amygdala, and the entorhinal cortex. Smells and
memories/emotions = so close to the limbic system Visual pathways: Basic pathways and areas involved: Geniculostriate pathway- basic vision pathway. From the eye, through the optic tract, the lateral geniculate nucleus (thalamus), sent to the striate cortex of the occipital lobe, moves through the
occipital lobe to be processed in other areas. The conscious vision that we are aware of. Secondary visual pathway: Tectopulvinar pathway: brain stem to the thalamus, unconscious. visual information goes from the eye, through the optic tract, to the superior colliculus (midbrain), to the posterior
part of the thalamus, the pulvinar, then to other visual cortical areas. Not aware of, fish and animals rely on this pathway. If we have damage to the first pathway, but we still have this pathway, then we have blindsight. Ability to react to visual stimuli without being conscious of it. Sensory receptor
neurons communicate to the cortex via several connecting interneurons. Relays allow sensory systems to produce relevant actions. Identify change- rapidly vs slowly adapting. Identify the presence of a stimulus. Identify self vs other- exteroceptive: outside vs interoceptive-inside.Density determines
sensitivity. Touching a stove: Pain receptors in the spinal cord trigger reflexes that produce withdrawal movements. Pain pathways in the periaqueductal gray matter (PAG) trigger behavioral activation, emotional responses, and longer-lasting pain. Cortex identifies the felt pain, its external cause, and
possible remedies. Also, helps us adapt our experience. Sensation= objective. Perception= subjective. . Chapter 9: Motor Systems Basic pathways and areas involved: send efferent information from most posterior part of the frontal lobe M1, which tell muscles to contract. Citicoline is released, tells
muscle fibers to contact. 1: Primary motor cortex: bark over the brain. A strip of cortex that is important for voluntary movement. The only region that can evoke movement. Basal Ganglia: Modulating movement. Volume control, making sure movement is appropriate for the circumstance. The
subcortical structure must cut the brain open to see. Projections from substantia nigra (midbrain) Dopaminergic system- Niagara striatal is important for controlling movement Disorders include Huntington-hyperkinetic disorders, Tourette’s-hyperkinetic disorders, Parkinson’s-hypokinetic disorder.
Cerebellum: Balance gets information from proprioception- where we are in space. Important for motor learning, timing, and accuracy. Classical conditioning happens here. Adaptation too; our brain adapts and compensates. Spinal cord: Important for voluntary movement. Travel from the brain
down the spinal cord to activate muscles. Pyramid cells in the cortex project to the brainstem and spine. Natural movements: prewired movement, we do a lot. Graziano’s research: preprogrammed shortcut to enact certain movement. Each representation of the body is responsible for a somewhat
different movement. We can represent specific natural movements in our cortex. Instead of each movement being pieced together, we have shortcuts. Whole body movements (more complex) represented in the premotor cortex; more discrete (less complex) movements in the motor cortex. Mirror
neurons: goal-oriented movement. generally located in the left hemisphere, in the premotor cortex. Active when you watch someone else move. \Have a role in self-action, perception of action, self-awareness, and awareness of the intention and actions of others. Important for gestures and verbal
language. Fewer mirror neurons- struggle with empathy. Autism disorders are where we see diff mirror neurons. the suspense is goal-oriented.
3 Long-term potentiation: change in an action potential that lasts. cells that fire together, wire together. Persistent strengthening of synaptic connections between neurons in response to activity. Memories create physical changes in the brain. Change in presynaptic cell- changes in calcium
channels and in the postsynaptic cell- more receptors for the neurotransmitters, or more dendrites - happens because of calcium channels. An action potential reaches the terminal, calcium channels open and signal for the neurotransmitter to be released. Also with plasticity, change in the brain in
response to experience or learning. Explicit: Episodic memory: autobiographical experience, has a place in time. Contributes to autonoetic awareness. G>O> case study -> KC couldn’t remember past personal experiences or imagine the future. Explicit: Conscious Explicit: Semantic memory:
facts/knowledge. Nonautobiographical knowledge. Intact in HM and other patients with ventral prefrontal and medial temporal lobe damage. Implicit memory: unconsciousness. skills, habits, priming, conditioning. Memory of learned skills or reactions that are unconscious. Emotional; conscious and
unconscious. attraction, avoidance, fear. Involves the amygdala. Both implicit and explicit aspects of memory. Short term/working memory: things like rehearsal. Sensory ex: habituation, motor, cognitive. Frontal lobe – dorsolateral prefrontal cortex 3 theories of memory: System consolidation
theory: role of the hippocampus is to consolidate memories, making them permanent, hold them for a time, and send them to be stored elsewhere in the brain. Accounts for the preservation of old memories. Multiple trace theory: memory rarely consists of a single trace or neural substrate, when
we have brain damage, we don’t lose all memory is stored and dispersed across the brain. Reconsolidation: each time a memory is used, it is reconsolidated. A memory enters a liable phase when its recalled and is then restored as a new memory. Results in many different traces for the same event.
Temporal/Rhinal cortex- around hippocampus in medial temporal lobe. Hippocampus- medial structure, not cortex. Subcortical. Surrounded by cortex- perirhinal. Rhinal cortex that surrounds the hippocampus. Damage to the hippocampus produces impairment when the task includes context.
Damage to the rhinal cortex produces severe anterograde/retrograde impairments on object recognition tests. Seahorse shape. Important for creating new memories =. Ventral: “Vut” Uncinate fasciculus: white matter tract, myelinated axons of a neuron. connecting frontal and temporal lobe.
Important for memory, communication is important for memory formation and retrieval. Amnesias- retrograde- old, previous to an accident, unable to have old memories. Anterograde- unable to form new memories, maintain old memories. infantile- can’t form early episodic memories, like
childhood memories. – because we don’t have language before then? Maybe because of synaptic pruning? Fugue: dissociative. Don’t know what happened for a brief period of time: blackout drunk. Laterality: Right temporal cortex: Deficits in face recognition, spatial position, maze learning. Left
temporal cortex: Deficits in word lists, nonspatial association, recurring digits test. Right prefrontal cortex: retrieval. Left prefrontal cortex: encoding. Language: Continuity: developments in language, language has continuously evolved. Discontinuity: it’s a big jump from nonhuman ancestors to
human language speech. Only humans can do it. Ape: learned complex language communication skills. Can learn human-like language even though they don’t have vocal cords using the core skills. Parrot: does have vocal cords and tongue, can create compound words. The parrot was trained to do
complex problem solving and create new sentences and answer new problems that he had never been exposed to. FOXP2 gene- discontinuity hypothesis: genetic allele that is associated with changes in articulation- how we move our mouth and lips to make speech sounds. Gene that was mutated
people have severe speech Impediments. Discovered because the family in the UK had a genetic family-wide pattern of severe speech. found a mutation in their FOXP2 gene. The genetic mutations at the level of the genome, the nucleus, leads to differences in the brain area, there is dispersed
activity all over the cortex for people with mutation. For people who don’t have the mutation, their activation during speech task is in the frontal lobe called Broca’s area- associated with the production of speech – left hemisphere. Core skills- Categorization/schemas: must be able to have broad
