Neurobiology of emotion final

sequence of events causing rage in the brain

1) brain (amygdala) alerted by external stimuli

2) bypasses the logic center and goes straight to primitive brain

3) brain triggers adrenaline and testosterone hormones under attack

4) blood pumps faster, increased cardiovascular talk louder and quicker

5) as blood pumps, more hormones produced creating more anger

6) take 20 min to move from the emotional brain to thinking brain again

some crucial structures involved in creating the reactions to fear

- thalamus: directs info to other parts of the brain

- hippocampus: sensory cortex and amygdala, areas of the brain that establish situational and emotional context and officially deem the situation as fearful

- hypothalamus: where the fight-or-flight response is activates. messages are sent to kidneys' adrenal glands which release stress hormones

- frontal and temporal lobes: higher cortical areas where experiences of dread occurs, release chemicals like dopamine that can cause panicked irrational behavior

functional aspects of the amygdala

- the amygdala plays an important role in evaluating emotional stimuli

- the amygdala and orbitofrontal cortex play essential roles in organization of emotional responses and its translation into actions

- the cingulate gyrus is related to motivation

LeDoux defines the amygdala was a

center for emotional evaluation

the amygdala receives

- rapid and crudely processes info from the doors-medial thalamus and the nucleus of the solitary tract

- slower and more processed info from the ventral thalamus and successive stages of cortical processing (sensory pathways)

the amygdala can evaluate ______

stimuli

order of amygdala processing stimuli

stimuli --> amygdala --> response

- conscious mind evaluates if it is a correct response and sends it back to the amygdala if it is

expression of different emotional responses by the amygdala

- pathways from the cerebral cortex offer detailed and accurate representations of the environment

- bc these pathways have multiple neural links they are slow by comparison

- If a person sees a slender curled shape behind a tree its much better to jump back and later recognize its a garden hose than to fail to quickly jump back if it was a snake

emotional stimuli goes to the _______ ______

auditory thalamus

the auditory thalamus sends signals to

- auditory cortex

- auditory association cortex

- lateral nucleus of the amygdala

the auditory association cortex sends signals to

- lateral nucleus

- perirhinal cortex

the prirhinal cortex sends signals to

- entorhinal cortex

- lateral nucleus

the entorhinal cortex send signals to

- hippocampus

the hippocampus sends signals to

- amygdala

- subiculum

the subiculum sends signals to

- amygdala

- entorhinal cortex

the central nucleus of the amygdala sends signals to

- bed of nucleus of the stria terminalis --> stress hormones

- parabrachial --> parasympathetic controrl

- central gray --> emotional behavior

- lateral hypothalamus --> sympathetic activation

- nucleus reticularis pontis caudalis --> reflex potentiation

there are direct connections from the amygdala to

- HPA axis

- cerebellum

- sensory neocortex

- MRL memory system (hippocampus, entorhinal cortex, perirhinal cortex)

- PFC

- striatum

there are indirect connections from other regions to the amygdala

- cerebellum

- PFC

- striatum

there are indirect connections to and from the amygdala and

PFC

activity in threat-related neural network is increased in people with _______ ______

anxiety disorders

neuroplasticity in the maternal brain

- essential in parental warmth

- activation of neuroplasticity is a factor in brain circuits that ultimately regulate maternal affective regulation of outcomes of caregiving

mother's own experience of maternal warmth affect

- mother infant adaptive attachment

- pre-parenthood affective disorders

pre-parenthood affective disorders affect

- mother's own experience of maternal warmth

- postpartum maladaption

mother-infant adaptive attachment affects

- postpartum maladation (and vice-versa)

brain regions involved in plasticity in maternal brain

- DLPFC and VLPFC (executive control)

- dorsal ACC and ventral ACC (fear regulation) hippocampus

- amygdala insula (salience/fear processing)

mother's own experience of maternal warmth is correlated with

DLPFC

pre-parenthood affective disorders are correlated with

VLPFC

maladaptive neuroplasticity

main cause of symptoms in chronic neuropathic pain, spasticity, and some forms of tinnitus

emotions can affect the _____ _____

immune system

- can affect inflammatory processes

the role of the immune system

- BDNF can be increased by physical exercise and administration of more omega 3

- the ratio btw omega 6 and omega 3 can be easily decreased by intake of more omega 3

immune cells in the small intestine affect the function of many parts of the _______ _______

nervous system

the functional anatomy of the inflammatory reflex

- neuronal interconnections btw the NTS, A P, DMN, NA, and higher forebrain regions integrate afferent signaling and efferent vagus nerve-mediated immunoregulatory output

- efferent vagus nerve cholinergic output to the spleen, liver and GI tract regulates immune activation and suppresses pro inflammatory cytosine release

- this efferent cholinergic arm of the inflammatory reflex can be activated in the brain through mAChR-mediated mechanisms triggered by mAChR ligands and AChE inhibitors, like galantamine

microglia are the primary recipients of ______ _______ _______ as they reach the brain

peripheral inflammatory signals

example of damage to the amygdala

kluver-bucy syndrome

Dr. Hayman reported the signs of damage to the amygdala in a patient with isolated symmetric damage to the amygdala and their cortical connections to be...

- psychic blindness, inability to recognize emotional importance of events

- hyper-sexuality

- altered emotional behavior, particularly placidity

- hyperorality and the ingestion of inappropriate objects

- a tendency to react to every visual stimuli

- memory deficits

Dr. Adolphs and colleagues say...

- data showed that bilateral damage to amygdala impairs judgements of the intensity of expression of fear, and of expressions normally judged to be very similar to fear

- damage to the amygdala impairs processing of some facial expressions of emotion

- recognition of fear appears to be the most severely impaired

Adolphs summarized that the human amygdala is indispensable to...

- recognize fear in facial expressions

- recognize multiple emotions in single facial expression

- but it is not required for recognizing personal identity from faces

- so damage restricted to amygdala causes particular recognition impairments and thus forces the notion that the amygdala is involved in emotion

some effects of a release of oxytocin

emotional:

- anxiolysis

- positive mood

social:

- maternal behavior

- pair bonding

- sexual behavior

cognitive:

- social memory

- olfactory memory

neuroendocrine:

- anorexiant effect

- attentuation of HPA axis response to stress

autoergulation:

- auto excitation during birth and suckling

oxytocin may increase... and decrease...

- gain in the amygdala

- sensory precision in the hypothalamic region

dopamine has _______ effects mediated by _____ and ______ receptors

complementary

- D1 (go pathway)

- D2 (no-go pathway)

deficits of oxytocin may lead to a

failure of interoceptive processing

dopamine deficits

compromise proprioceptive processing and the initiation of action

- like in Parkinson's disease

oxytocin and dopamine in the amygdala

in both cases, context sensitive neuromodulatory signaling is listed by descending projections from cortical regions involved in emotional regulation (oxytocin) or action selection (dopamine)

positive social interaction, such as physical contact, is associated with ______ ______ that further promote social approach behavior

oxytocin release

oxytocin reduces ______ and ______ _______ reactivity to social strressors

amygdala and HPA axis

oxytocin and vasopressin (antidiuretic hormone) in bonding

- these neurons and their projections to selected brain regions that are important in social behaviors

- these 2 are released from the pituitary gland into the blood circulation to regulate peripheral functions such as the milk letdown reflex and uterine contractions in females as well as vasoconstriction and water retention in both males and females

oxytocin and vasopressin are also released throughout the brain to regulate a variety of complex social behaviors including....

- social recognition

- mating

- bonding

- parrenting

- social buffering

the role of estradiol in fear extinction and psychopathology

studies have indicated a correlation btw fluctuating estradiol states and vulnerability for fear and anxiety disorders

future directions for exploring the role of estradiol in fear extinction and pathology

where

- where does estradiol modify neural functions?

- where does estradiol act within the fear extinction network to modulate fear extinctions?

how

- how is estradiol influencing fear extinction induced cellular and molecular mechanisms?

- how can these mechanisms be targeted or modulated?

when

- when, during the different phases of the menstrual cycle, is drug treatment most effective?

- when could estradiol be used as an adjunct to clinical intervention and/or treatment?

cumulative incidence of 18 chronic conditions considered separately in women with and without bilateral oophorectomy

- 5 women = mental health conditions

- 7 women = cardiovascular or metabolic conditions

- 6 women = other somatic conditions

possible interpretation of the findings of removal of ovaries

A) genetic variants or behavior environmental risk facts can DIRECTLY lead to accelerated aging (--> multi morbidity and morality) and gynecological conditions (--> bilateral oophorectomy)

B) bilateral oophorectomy (primarily) and genetic variants or behavioral and environmental risk factors (secondly) can DIRECTLY lead to only accelerated aging --> multimorbidity and mortality

C) genetic variants or behavioral enviornmental risk factors DIRECTLY lead to accelerated aging (--> multi morbidity and mortality) and INDIRECTLY lead to gynecological condition (--> bilateral oophorectomy) through accelerated aging

somatic and visceral sensory neurons -->

sensory (afferent) division

sensory (afferent) division -->

PNS

PNS -->

motor (efferent) divisions

motor division -->

somatic and autonomic nervous system

autonomic nervous system -->

sympathetic and parasympathetic division

anatomical differences in sympathetic and parasympathetic divisions

comes from different regions of the CNS

- sympathetic --> from the thoracolumbar region

- parasympathetic --> from the carniosacral region

differing locations of ganglia

- sympathetic --> close to spinal cord in a chain

- parasympathetic --> close to target organs

differing lengths of postganglionic fibers

- sympathetic --> long

- parasympathetic --> short

postganglionic branching

- sympathetic --> lots, so that multiple organs can be mobilized at once

- parasympathetic --> very little branching

hypothalamus-pituitary-adrenal cortex (HPA)

- hypothalamus send corticotropin releasing hormone (CRH)--> anterior pituitary

- anterior pituitary sends adrenocorticotropic hormone (ACTH) --> adrenal cortex

- adrenal cortex releases cortisol (CORT)

and CORT regulates hypothalamus and anterior pituitary through negative feedback inhibition

fear-signaling impulses from the central nucleus of the amygdala activates the _______ _______ ______ and modulates the ______ ______

sympathetic nervous system; HPA axis

hypothalamic-pituitary-adrenal (HPA) axis vs hypothalamic-pituitary-gonadal (HPG) axis

HPA axis is activated by....

stress signals that travel from the paraventricular nucleus (PVN) of the hypothalamus to the pituitary gland and then to the adrenal glands for glucocorticoid release

in the HPG axis....

the hypothalamus produces gonadotropin-releasing hormone, which binds to receptor within the anterior pituitary to release LH and FSH

LH and FSH then stimulate the

gonads to release estrogen and progesterone, as well as a small amount of testosterone, in females

estrogen levels can regulate _____ ______

HPA responses

HPA activity can inhibit ______ _______

estrogen secretion

the reciprocal modulation of gonadal hormone and stress response underlie the _____ _____ and influence of the _____ _____ in fear extinction and anxiety disorders

sex differences; gonadal hormones

cortisol in HPA and estrogen progesterone in HPG inhibit

PVN and anterior pituitary

cortisol also inhibits

ovaries

in the illness response, what affects central representations of protective body functions

- feedback from the body: neuronal, hormonal, immune signals

- illness responses including pain and hyperalgesia (also affected by central representations)

- environment perturbations

central representations of protective body functions affects

- neuroendocrine responses

- autonomic responses

- motor responses

neuroendocrine responses and autonomic responses lead to

adaptation of organ functions, inflammatory reactions, and immune responses

autonomic responses and motor responses lead to

adaptation to environment

activation of survival circuit direct consequences

- sensory systems

- cognitive systems

- modulatory systems

- explicit memory systems

- motivational systems

- hormonal responses

- ANS responses

- innate behavioral responses

- learned instrumental goal directed behavior

there is generalized arousal from the modulatory systems to

- cognitive systems

- explicit memory systems

- motivational system

- survival circuit

- sensory systems

there is body feedback to the entire circuit from

- innate behavioral responses

- ANS responses

- hormonal responses

- learned instrumental goal-directed behavior

emotional stimuli can affect the _____ which can affect the ______

heart; brain

the vagus nerve provides two-way connections btw the _____ and ____ _____ in the body including the _____

brain; many organs; heart

the descending part of the vagus nerve provides _____ _____ of the function of organs in the abdomen, including the heart

parasympathetic control

the ascending parts of the vagus nerve make it possible for organs in the abdomen and chest to influence the _____ _____

emotional brain

the ascending vagus nerve fibers terminate on cells in the _____ _____ _____ and in that way it communicates info from organic in the abdomen to the brain

nucleus tractus solitarius

activity in the ascending part of the vagus nerve reaches the _____ _____ which provides arousal to cortical cells and facilitate neuroplasticity

basal nucleus

other parts of the brain that play a role in creating emotional responses

- bed nucleus of stria terminalis

- periaqueductal gray

- frontal and prefrontal cerebral cortices

- the thalamis

- hippocampus

- hypothalamus

- immune system

- autonomic nervous system

the cerebral cortex

- plays a role in some forms of discrimination of sensory stimuli such as discrimination of objects that may be dangerous

- cerebral cortex does not play a role in fear conditioning

the hippocampus sits on top of the cortical hierarchy and can encode info from all over the brain, binding it together with ______ _____

episodic memory

the basolateral and central nuclei of the amygdala are involved in _____ ______ in a complicated way through interaction btw many dif systems

memory consolidation

stimulation that reaches the basolateral nucleus of the amygdala either from the _______ or the _____ _____ can change synaptic efficacy as an expression of learning

thalamus; cerebral cortex

_______ _______ enhance memory consolidation, but it is remarkable that the same does of _______ that enhances consolidation of memory can impair retrieval of memory

adrenergic substances; glucocorticoids

Dr. McGaugh has shown that learning of emotional events depends on adrenergic substances and that learning is impaired after administering a ___-______ -_____ such as _______

6-adrenergic blocker; propranolol

______ of ______ ______ is also affected by adrenergic substances

retrieval of learned information

the relationship btw effectiveness in retrieval of memory and the concentration of adrenergic substance is an _____ ____ _______ curve

inverted U shaped curve

thus, the effectiveness of retrieval ______ with increased adrenergic concentrations (increased stress) to reach the maximal effect after which _______ in the adrenergic concentration impairs retrieval

increases; increases

emotional stimuli can activate the visceral system through 3 different routes

- using the amygdala

- using orbitofrontal cortex

- using the anterior cingulate cortex and insular cortex

the root of all disease

gut-brain system

the digestive system and the brain communicates in _____ _____

both directions

the cerebellum plays an important role in the _______ of _______ such as _____, related to its connections to the ANS

expression of emotions; fear

inactivation of the cerebella vermis during the consolidation period hampers the ______ of ______ ______ ______

retention of fear memory traces

the cerebella vermis participates in fear learning and memory mechanisms related to the ______ of ______ and _______ responses of emotions

expression of autonomic and motor responses

the cerebellum is activated during

- mental recall of emotional personal episodes

- learning of a conditioned or unconditioned association involving emotions

the insular lobe may be the site of ______ symptoms

unexplained

new understanding of its functions comes from the use of a _______ _______ in ______

diagnostic method in neurosurgery