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Jaak Panksepp

Publications and source records attributed to Jaak Panksepp.

At least 19 recordsLinked to original sources
PubMed2006

Emotional endophenotypes in evolutionary psychiatry.

Evolutionary psychiatry emerged from the conceptual successes of sociobiology and evolutionary psychology. It will need to avoid the many mistakes that biology-free Evolutionary Psychology has been prey to. It should not ignore the wealth of information that exists between the phenotypic expression of symptoms and the genotypic sources of core brain/mind processes that are disrupted in psychiatric disorders. Syndromal-conceptual thinking has become a barrier to illuminating the biological sources of psychiatric disorders. Endophenoytpic-biomarker approaches now offer robust alternatives for generating linkages between psychiatrically relevant psychological changes and the neurobiological infrastructure of disordered mentation. Here I summarize recent advances in endophenotypic thinking in biological psychiatry, and suggest that various core emotional-affective processes may be among the most important endophenotypes that need to be clarified at both neurobiological and genetic levels of analysis. To this end, I discuss strategies to link basic emotional processes that are commonly imbalanced in psychiatric disorders to neuroanatomical, neurochemical, neurophysiology, and molecular genetic levels of analysis. Conjoint animal behavioral-genetic and gene expression, microarray analyses can clarify a variety of key emotional endophenotypes and thereby provide a coherent infrastructure for psychiatric systematics. To further clarify the neurobiological dimensions of psychiatric disorders, we must also focus on psychosocial and environmental stress vectors that converge to create imbalanced emotional and motivational brain activities of psychiatric significance.

Animals↗
PubMed2006

Self-referential processing in our brain--a meta-analysis of imaging studies on the self.

The question of the self has intrigued philosophers and psychologists for a long time. More recently, distinct concepts of self have also been suggested in neuroscience. However, the exact relationship between these concepts and neural processing across different brain regions remains unclear. This article reviews neuroimaging studies comparing neural correlates during processing of stimuli related to the self with those of non-self-referential stimuli. All studies revealed activation in the medial regions of our brains' cortex during self-related stimuli. The activation in these so-called cortical midline structures (CMS) occurred across all functional domains (e.g., verbal, spatial, emotional, and facial). Cluster and factor analyses indicate functional specialization into ventral, dorsal, and posterior CMS remaining independent of domains. Taken together, our results suggest that self-referential processing is mediated by cortical midline structures. Since the CMS are densely and reciprocally connected to subcortical midline regions, we advocate an integrated cortical-subcortical midline system underlying human self. We conclude that self-referential processing in CMS constitutes the core of our self and is critical for elaborating experiential feelings of self, uniting several distinct concepts evident in current neuroscience.

Attention↗
PubMed2005

Play behavior in rats pretreated with scopolamine: increased play solicitation by the non-injected partner.

Play behavior was assessed in juvenile rat pups following chronic administration of scopolamine (0.5 or 1.0 mg/kg, i.p.) to one partner in each dyad of rats. Scopolamine administration significantly reduced the number of pins and mean pin duration of both playmates in pairs where only one rat was injected with scopolamine (irrespective of dose). However, dorsal contacts were significantly increased in rats exposed to a play partner that had been injected with scopolamine, indicating an increase in play solicitation when the partner was rendered non-responsive with this drug. These effects were stable and consistent over the course of 15 days of repeated testing in the presence of scopolamine. In other words, normal animals did not extinguish play solicitation even after prolonged periods of non-reciprocity. Upon cessation of drug treatment, play behavior returned largely to normal in both animals. Overall locomotor activity levels were significantly reduced in pairs where one rat had been injected with scopolamine. Together, these data suggest that the effects of repeated scopolamine are acute in nature, and that disruption of normal play behavior following chronic scopolamine treatment does not produce long-term impairments in social play behavior beyond acute action of the drug.

Analysis of Variance↗
PubMed2005

Regional brain cholecystokinin changes as a function of rough-and-tumble play behavior in adolescent rats.

Brain cholecystokinin (CCK) levels have been shown to be elevated in animals defeated during adult social aggression. The present experiment evaluated whether similar effects are evident in prolonged bouts of juvenile social-play fighting, which tend to switch from largely positive to some negative affect after approximately 15 min into a half-hour play session, as indexed by a gradual shift from positively valenced 50 kHz ultrasonic vocalizations (USVs) to negatively valenced 20 kHz USVs. Given the role of CCK in both positive and negative emotional events, we examined levels of CCK-8 in tissue homogenates from 14 brain areas in animals 6h after a 30 min play bout compared to no-play control animals tested similarly in isolation for 30 min. As with patterns observed following adult defeat, significantly higher CCK levels were evident after play in the posterior neo-cortex compared to no-play control animals (+26%). Levels of CCK were also elevated in the midbrain (+35%). However, unlike in adult aggression, CCK levels were reduced in the hypothalamus (-40%) and basal forebrain (-24%) as compared to no-play animals. Posterior cortex CCK levels were positively correlated to the duration that each animal was pinned (r = +.50) which suggests that elevated CCK in the posterior cortex may be related to the negative aspects of play. Hypothalamic CCK levels were negatively related to dorsal contacts and pins (r's = -.57), and suggest that the lower CCK levels may reflect the more positive valenced aspects of play. The data indicate that CCK utilization in the brain is dynamically responsive to rough-and-tumble play.

Animals↗
PubMed2005

The neurobiology of positive emotions.

Compared to the study of negative emotions such as fear, the neurobiology of positive emotional processes and the associated positive affect (PA) states has only recently received scientific attention. Biological theories conceptualize PA as being related to (i) signals indicating that bodies are returning to equilibrium among those studying homeostasis, (ii) utility estimation among those favoring neuroeconomic views, and (iii) approach and other instinctual behaviors among those cultivating neuroethological perspectives. Indeed, there are probably several distinct forms of positive affect, but all are closely related to ancient sub-neocortical limbic brain regions we share with other mammals. There is now a convergence of evidence to suggest that various regions of the limbic system, including especially ventral striatal dopamine systems are implemented in an anticipatory (appetitive) positive affective state. Dopamine independent mechanisms utilizing opiate and GABA receptors in the ventral striatum, amygdala and orbital frontal cortex are important in elaborating consummatory PA (i.e. sensory pleasure) states, and various neuropeptides mediate homeostatic satisfactions.

Affect↗
PubMed2005

Breeding for 50-kHz positive affective vocalization in rats.

Adolescent and adult rats exhibit at least two distinct ultrasonic vocalizations that reflect distinct emotional states. Rats exhibit 22-kHz calls during social defeat, drug withdrawal, as well as in anticipation of aversive events. In contrast, 50-kHz calls are exhibited in high rates during play behavior, mating, as well as in anticipation of rewarding events. The neurochemistry of 22-kHz and 50-kHz calls closely matches that of negative and positive emotional systems in humans, respectively. The aim of this study was to replicate and further evaluate selective breeding for 50-kHz vocalization, in preparation for the analysis of the genetic underpinnings of the 50-kHz ultrasonic vocalization (USV). Isolate housed adolescent rats (23-26 days old) received experimenter administered tactile stimulation (dubbed "tickling"), which mimicked the rat rough-and-tumble play behavior. This stimulation has previously been shown to elicit high levels of 50-kHz USVs and to be highly rewarding in isolate-housed animals. Each tickling session consisted of 4 cycles of 15 seconds stimulation followed by 15 seconds no stimulation for a total of 2 min, and was repeated once per day across 4 successive days. Rats were then selected for either High or Low levels of sonographically verified 50-kHz USVs in response to the stimulation, and a randomly selected line served as a control (Random group). Animals emitted both 22-kHz and 50-kHz types of calls. After 5 generations, animals in the High Line exhibited significantly more 50-kHz and fewer 22-kHz USVs than animals in the Low Line. Animals selected for low levels of 50-kHz calls showed marginally more 22-kHz USVs then randomly selected animals but did not differ in the rate of 50-kHz calls. These results extend our previous findings that laboratory rats could be bred for differential rates of sonographically verified 50-kHz USVs.

Affect↗
PubMed2005

Affective consciousness: Core emotional feelings in animals and humans.

The position advanced in this paper is that the bedrock of emotional feelings is contained within the evolved emotional action apparatus of mammalian brains. This dual-aspect monism approach to brain-mind functions, which asserts that emotional feelings may reflect the neurodynamics of brain systems that generate instinctual emotional behaviors, saves us from various conceptual conundrums. In coarse form, primary process affective consciousness seems to be fundamentally an unconditional "gift of nature" rather than an acquired skill, even though those systems facilitate skill acquisition via various felt reinforcements. Affective consciousness, being a comparatively intrinsic function of the brain, shared homologously by all mammalian species, should be the easiest variant of consciousness to study in animals. This is not to deny that some secondary processes (e.g., awareness of feelings in the generation of behavioral choices) cannot be evaluated in animals with sufficiently clever behavioral learning procedures, as with place-preference procedures and the analysis of changes in learned behaviors after one has induced re-valuation of incentives. Rather, the claim is that a direct neuroscientific study of primary process emotional/affective states is best achieved through the study of the intrinsic ("instinctual"), albeit experientially refined, emotional action tendencies of other animals. In this view, core emotional feelings may reflect the neurodynamic attractor landscapes of a variety of extended trans-diencephalic, limbic emotional action systems-including SEEKING, FEAR, RAGE, LUST, CARE, PANIC, and PLAY. Through a study of these brain systems, the neural infrastructure of human and animal affective consciousness may be revealed. Emotional feelings are instantiated in large-scale neurodynamics that can be most effectively monitored via the ethological analysis of emotional action tendencies and the accompanying brain neurochemical/electrical changes. The intrinsic coherence of such emotional responses is demonstrated by the fact that they can be provoked by electrical and chemical stimulation of specific brain zones-effects that are affectively laden. For substantive progress in this emerging research arena, animal brain researchers need to discuss affective brain functions more openly. Secondary awareness processes, because of their more conditional, contextually situated nature, are more difficult to understand in any neuroscientific detail. In other words, the information-processing brain functions, critical for cognitive consciousness, are harder to study in other animals than the more homologous emotional/motivational affective state functions of the brain.

Affect↗
PubMed2005

Why does separation distress hurt? Comment on MacDonald and Leary (2005).

Evidence is substantial that separation-distress circuitry in animal models is related intimately to opioid-sensitive pain regulatory systems of the brain. The evidence that basic pain-affect mechanisms are integral to the feelings of defensive fear anxiety and aggression is modest. Although anger and anxiety can be reduced by opiates, the effects are not as robust and specific as those observed with the low doses that quell separation distress. The role of "social pain" may be larger for the affective underpinnings of jealousy, shame, and guilt (all variants of social exclusion and abandonment) than for fear and aggression. Interdisciplinary insights might be facilitated by more forthright analyses of how affective states are created within the brain. This will require better dialogue between behavioral neuroscientists and the rest of psychology interested in foundational psychoevolutionary issues.

Animals↗
PubMed2004

Regional brain cholecystokinin changes as a function of friendly and aggressive social interactions in rats.

Cholecystokinin (CCK) is the most abundant neuropeptide in the mammalian brain, and has been implicated in the regulation of a diversity of emotions and motivations including negative affect and stress responses. In this experiment, we assayed levels of CCK (CCK4/5 and CCK8) from tissue homogenates in intruder animals 6 h after resident-intruder inter-male aggression. Intruder animals that demonstrated submissive behavior (freezing and 22-kHz ultrasonic vocalizations) had higher levels of CCK in the tegmentum and posterior cortex as compared to non-submissive (i.e., "Friendly") intruder animals. Ultrasonic vocalizations (22-kHz) were positively correlated with CCK levels in the tegmentum, posterior cortex and pituitary. These data suggest that CCK may play a role in the generation of negative affective states indexed by 22-kHz ultrasonic calls in certain regions of the brain.

Aggression↗
PubMed2003

Neuroscience. Feeling the pain of social loss.

Poets have long waxed lyrical about the pain of a broken heart. Now, as Panksepp explains in his Perspective, this metaphor may reflect real events in the mammalian brain. A new brain neuroimaging study (Eisenberger et al.) reveals that the brain areas that are activated during the distress caused by social exclusion are also those activated during physical pain. Thus, we now have an explanation for the feeling of physical pain that accompanies emotional loss-whether that be the loss of a loved one, rejection by one's social group, or the distress of separation experienced by young animals.

Animals↗
PubMed2003

Socially-induced brain 'fertilization': play promotes brain derived neurotrophic factor transcription in the amygdala and dorsolateral frontal cortex in juvenile rats.

Rough and tumble (R&T) play is assumed to have beneficial effects in developing organisms. To evaluate this idea, brain derived neurotrophic factor (BDNF) gene expression was evaluated in 32-day-old juvenile rats that were allowed to play for 30 min prior to sacrifice. In situ hybridization for BDNF mRNA revealed that the amygdala and dorsolateral frontal cortex had significantly elevated BDNF mRNA expression as a result of play. These effects suggest that play may help program higher brain regions involved in emotional behaviors.

Age Factors↗
PubMed2003

High frequency repetitive transcranial magnetic over the medial cerebellum induces a shift in the prefrontal electroencephalography gamma spectrum: a pilot study in humans.

In the present study the anatomical projections from the medial cerebellum to the prefrontal cortex (PFC) were investigated in healthy human subjects, using high frequency repetitive transcranial magnetic (rTMS) stimulation and electroencephalography (EEG). Medial cerebellar rTMS, compared to placebo induced a significant shift in anterior asymmetry, from left to right dominance in the fast (30-50 Hz) EEG spectrum, whereas occipital and lateral cerebellum stimulation did not show such an effect. Moreover elevations in mood and alertness were reported again after medial cerebellar stimulation only. Taken together, these data confirm and further specify the assumed cerebellar modulation of PFC activity and affect.

Adult↗
PubMed2003

"Laughing" rats and the evolutionary antecedents of human joy?

Paul MacLean's concept of epistemics-the neuroscientific study of subjective experience-requires animal brain research that can be related to predictions concerning the internal experiences of humans. Especially robust relationships come from studies of the emotional/affective processes that arise from subcortical brain systems shared by all mammals. Recent affective neuroscience research has yielded the discovery of play- and tickle-induced ultrasonic vocalization patterns ( approximately 50-kHz chirps) in rats may have more than a passing resemblance to primitive human laughter. In this paper, we summarize a dozen reasons for the working hypothesis that such rat vocalizations reflect a type of positive affect that may have evolutionary relations to the joyfulness of human childhood laughter commonly accompanying social play. The neurobiological nature of human laughter is discussed, and the relevance of such ludic processes for understanding clinical disorders such as attention deficit hyperactivity disorders (ADHD), addictive urges and mood imbalances are discussed.

Acoustic Stimulation↗
PubMed2003

At the interface of the affective, behavioral, and cognitive neurosciences: decoding the emotional feelings of the brain.

This article summarizes recent conceptual and empirical advances in understanding basic affective processes of hte mammalian brain and how we might distinguish affective from cognitive processes. Six reasons are advanced for distinguishing the two types of consciousness, including (i) the presence of experienced valence, (ii) cortical sub-cortical locus of control, (iii) different developmental trajectories, (iv) informational vs organic considerations, (v) differences in bodily expressions, (vi) differences in cerebral laterality. The position is advanced that to make progress on understanding the neurobiological nature of affect, we need to utilize experimental strategies different from those that are common in cognitive science.

Affect↗
PubMed2003

Modeling ADHD-type arousal with unilateral frontal cortex damage in rats and beneficial effects of play therapy.

It has been recently shown that human adolescents with Attention Deficit/Hyperactivity Disorder (ADHD) have frontal lobe deficits, especially on the right sides of their brains (). ADHD is commonly treated with psychostimulants which may have adverse consequences. Hence, less invasive therapies need to be developed. In the present work, we tested the ability of right frontal lesions to induce hyperactivity in rats. We also evaluated the effects of chronic play therapy during early adolescence to reduce both hyperactivity and the elevated playfulness later in development. Play therapy was able to reduce both hyperactivity and excessive playfulness. In additional work, we found that access to rough-and-tumble play in normal animals could enhance subsequent behavioral indices of behavioral inhibition (i.e., freezing in response to a startle stimulus) that appeared to be independent of increased fearfulness and fatigue. Overall, these results suggest that (1) neonatal frontal lobe lesions can be used as an animal model of the overactivity in ADHD and (2) rough-and-tumble play therapy may be a new useful treatment for ADHD.

Animals↗